Clubjazz - Honda Jazz & HR-V Forums
Honda Jazz Forums => Honda Jazz Mk4 2020 - => Topic started by: booty on June 18, 2021, 06:56:10 AM
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HONDA JAZZ HATCHBACK 1.5 I-MMD Hybrid EX 5dr eCVT (20-) new 28/5/2021. Telematics unit was activated on 8/6/2021. Car left in garage since that date, went to start on 17/6/2021 battery flat. What current is drawn from the battery while the car is left locked?
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Was the battery fully charged ?
Often the dealer just gives them a basic charge and it does take some weeks of discharge/charge to get it up to par.
Without that charge I could see a 2 week sit taking enough out of it to refuse to start.
If you can, get a CTEK and keep it charging till the CTEK goes green.
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How much distance had it done before you garaged it?
The telematics unit is unlikely to be the culprit. It's more likely that one of the interior lights was left on.
Incidentally, the manual recommends driving the car for a minimum of 30 minutes every three months to top up the high voltage battery.
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Incidentally, the manual recommends driving the car for a minimum of 30 minutes every three months to top up the high voltage battery.
I think it's more a case of making sure that the charge doesn't get too low. Unless one has a convenient big hill to drive down the battery doesn't go above 70% in normal usage. However, I think Honda is being cautious as the self-discharge of Lithium batteries is very low and I believe that the the battery is isolated when the car is switched off. It's the baby 12V lead-acid battery which is both vulnerable to self-discharge and meets any residual power demands. I believe that the telemetry system goes into sleep mode after a day or two to minimise the power drain.
I agree that the culprit could be a light. Check the boot light as if this is left on then it won't be obvious (tip: put an LED bulb which is not only brighter but also uses less power - I'm surprised that Honda didn't fit one as standard rather than offer it as an expensive option given it's cost is a few pennies). However, I've thought of a possible scenario. If there's no phone signal in the garage could the telemetry unit have been frantically trying to connect with the server without success to report the vehicle location etc when the engine was turned off?
My Crosstar spent two months of being parked either side of Christmas and I topped up the 12V battery with a charger every couple of weeks as I noticed that it was dropping to about 11.8V and I'd prefer, for the sake of battery longevity, for it to not sit with a low state of charge.
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Incidentally, the manual recommends driving the car for a minimum of 30 minutes every three months to top up the high voltage battery.
I think it's more a case of making sure that the charge doesn't get too low. Unless one has a convenient big hill to drive down the battery doesn't go above 70% in normal usage. However, I think Honda is being cautious as the self-discharge of Lithium batteries is very low and I believe that the the battery is isolated when the car is switched off. It's the baby 12V lead-acid battery which is both vulnerable to self-discharge and meets any residual power demands. I believe that the telemetry system goes into sleep mode after a day or two to minimise the power drain.
I agree that the culprit could be a light. Check the boot light as if this is left on then it won't be obvious (tip: put an LED bulb which is not only brighter but also uses less power - I'm surprised that Honda didn't fit one as standard rather than offer it as an expensive option given it's cost is a few pennies). However, I've thought of a possible scenario. If there's no phone signal in the garage could the telemetry unit have been frantically trying to connect with the server without success to report the vehicle location etc when the engine was turned off?
My Crosstar spent two months of being parked either side of Christmas and I topped up the 12V battery with a charger every couple of weeks as I noticed that it was dropping to about 11.8V and I'd prefer, for the sake of battery longevity, for it to not sit with a low state of charge.
I have a 2A trickle charger which I used to use on my Mk 2 without disconnecting the battery. Did you disconnect it before charging up the Crosstar?
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I have a 2A trickle charger which I used to use on my Mk 2 without disconnecting the battery. Did you disconnect it before charging up the Crosstar?
No - I leave the 12V battery connected. The charger is the previous version of one of these https://www.amazon.co.uk/gp/product/B07B9CFV7V . There's something strange about the battery charactistics as, when the battery is down to 11.8V according to my voltmeter (cross-checked previously against the voltage according to an OBDII reader) the charger will switch from charging to full after a few minutes (but I leave it connected for a few hours). I saw the same behaviour on my HR-V.
One point to note is that the -ve charger clip should be connected to the earth strap end of the Intelligent Battery Sensor and not directly to the -ve terminal so that the car knows that the battery is being charged.
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The manual suggests that the battery should be disconnected from the car if it's being charged. That might explain the strange results when trying to float charge it.
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The manual suggests that the battery should be disconnected from the car if it's being charged. That might explain the strange results when trying to float charge it.
That's generally because Honda don't know what charger you will be using. Smart chargers like the Ctec detect the battery, condition and environment and charge the battery safely without having to disconnect it.
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I've sort of hardwired my CTEK so I don't have to faff with crocodile clips. I have a plug under the bonnet and the CTEK has a plug. Takes seconds to connect.
However, we had a discussion on Civinfo and the conclusion we came to was to connect the positive to the battery but the negative to the car body, not the battery negative.
The reason for this was so the 'car' can calculate/recognise the charge for the stop/start. With the charger connected to battery negative stop/start did not recognise a full battery so turned it off.
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HONDA JAZZ HATCHBACK 1.5 I-MMD Hybrid EX 5dr eCVT (20-) new 28/5/2021. Telematics unit was activated on 8/6/2021. Car left in garage since that date, went to start on 17/6/2021 battery flat. What current is drawn from the battery while the car is left locked?
If the car was ok before the telematics was activated it could be a factor. As I garage mine at home I don't lock the car to save a bit of energy (I switch the remote off once inside the house).
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I've sort of hardwired my CTEK so I don't have to faff with crocodile clips. I have a plug under the bonnet and the CTEK has a plug. Takes seconds to connect.
However, we had a discussion on Civinfo and the conclusion we came to was to connect the positive to the battery but the negative to the car body, not the battery negative.
The reason for this was so the 'car' can calculate/recognise the charge for the stop/start. With the charger connected to battery negative stop/start did not recognise a full battery so turned it off.
To be fair all modern cars advise connecting a battery charger to the car body rather than the battery terminal.
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Hi Everybody and thank you for your replies. In answer to your replies:
The car was purchased on the 28th May 2021.The Telematics unit was not activated at the PDI check.
I am unsure how fully or not the battery was charged by the dealer when I took delivery. It as had a few runs out (180 miles) plus a 25 mile round trip to the dealer for the telematic setup on 8th June 2021.
I am unsure if I locked the car in the garage or it self locked after I left it, I only know it was locked when I came to use it on the 17th June and I opened the drivers door by using the key.
The garage is attached to the house and dark, no interior lights were left on, I am unsure about the boot light but after climbing through the car I could not see any boot light switch. I think it comes on if the hatch is opened.
I have been out all day today and not able to chase the dealer except by email which they have not replied to as yet.
I do have a CTEK charger but was reluctant to do anything myself as the car is not a month old yet.
I felt Honda assist should be called out to register the problem but would prefer a new fully charged battery to be fitted rather than a fast charge to my existing battery. After consideration I did connect my CTEK with the battery in situ, Red to positive and Black to chassis earth but after 2 lights light up on the charger the horn kept sounding so I removed the CTEK. As the car was left with the alarm set I think it's Honda Assist in the morning.
I did check the battery voltage with a Fluke multimeter this morning which read 2.44V and this evening 2.33V, a loss of 0.11V in 16 hours.
Hope its not too much of a novel. Thanks for reading it.
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Having the horn sound when a CTEK is connected is a worry as that's what I will be doing regularly being a low mileage driver now.
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After checking the manual regarding the battery going flat after the alarm had been set I went through the procedure to clear the alarm. I locked the car manually with the key, reconnected the Ctek charger to the battery but not to the mains, closed the bonnet and switched on the mains power to the ctek, when the alarm sounded I cleared it with the key fob. The Ctek has been changing all night, waiting for level 5 to complete at the moment. If the charging process completes I intend to monitor the battery voltage for a few days and recreate the situation.
I an lucky to have a camper van which I can use while the Jazz stands.
Hopefully I may hear from Honda but not impressed by their Aftersales so far.
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Got these for our motorbikes and cars.
The fused lead bolts onto battery ( or with start stop the negative lead will go to earth point on body ), the SAE plug is accessible by pulling out of grille ( cable tied to grille ) and the batteries can be easily charged without unlocking the car. The 'external charging' can come in useful if the battery ever goes completely flat and central locking ( or rather unlocking ) does not work.... On a motorbike it means no need to remove the saddle, and I also fitted a digital voltmeter to handlebars and use the SAE charging plug to plug that straight onto the battery, which cuts out any voltage drop in bikes wiring.
https://www.amazon.co.uk/gp/product/B01N7CEV00/
https://www.amazon.co.uk/KUNCAN-Extension-Battery-Disconnect-Connectors/dp/B01MZZGHNK/
https://www.amazon.co.uk/KUNCAN-Motorcycle-Extension-Disconnect-Connection/dp/B01N7CHYCF/
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Hi, with the cable you suggest for the battery, do you have to detach both battery cables before fitting it? That is, the battery has nothing connected, or can you just bolt it on to the positive terminal and the negative bolt before the battery monitor connection, battery cables in situ?
Thanks.
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Ctek chargers come with extensions which connect permanently to battery/body. Extension has terminal that plugs into the Ctek output cable.
To be honest a new Jazz should not need any attention to it's battery for years. Car driven normally should look after itself. If it doesn't there is something wrong and Honda need to fix it!
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Hi, with the cable you suggest for the battery, do you have to detach both battery cables before fitting it? That is, the battery has nothing connected, or can you just bolt it on to the positive terminal and the negative bolt before the battery monitor connection, battery cables in situ?
Thanks.
Just attach the ring terminals to 6mm bolts that hold battery clamps ( do not connect negative straight to battery terminal, but to the terminal next to it or the body metalwork nearby ), leave everything else connected as usual - most chargers now come with the SAE type connector plugs and will plug straight in.
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I would add that on the Mk 4 Jazz the 12V battery is charged from the HV system and doesn't have it's own alternator. A 25 mile trip should be more than enough to get the battery fully charged. Effectively, the 12V battery is a big capacitor to provide a stable supply of power for the 12V accessories. However, if the ECU uses the 12V supply could there be a scenario where a flat 12V battery stops the ECU from powering up and this might mean that the power button doesn't work for waking the system up to start charging the little battery from the big one.
I've just checked and note that there is no separate switch for the boot light which means that this shouldn't be a potential souce of battery drain unless the boot is not latched, in which case the vehicle won't lock.
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So a trickle charge device like a CTEK is useless on the MK4, interesting.
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So a trickle charge device like a CTEK is useless on the MK4, interesting.
No. Trickle charging if the vehicle has been standing for a couple of weeks keeps that puny 12V battery in better condition which is never a bad thing. If the battery loses capacity and the vehicle isn't used very frequently then there will be more occurences of flat battery resulting in the remote locking not working and maybe other undesirable effects. However, if there's enough life in the 12V battery to unlock the doors and power the ECU then the big battery does the engine starting.
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Thanks.
So the HV battery doesn't try to keep the 12v one topped up while standing. Just trying to get my head around it.
Shouldn't be a problem as I frequently do 2 x 30 mile journeys weekly. As opposed to daily before I retired.
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However, if there's enough life in the 12V battery to unlock the doors and power the ECU then the big battery does the engine starting.
Interesting. On my Toyota hybrid, the 12v battery never starts the engine and you cannot jump start the car in the traditional manner. Also, the charge going into the 12v battery is at such a low current you can't charge another car from it at any kind of meaningful pace. When my Jazz battery packed in a while back there was nothing I could do for it from the RAV4, so I no longer carry jump leads in the Toyota now, pointless. I do, however, have a towing cable.
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So the HV battery doesn't try to keep the 12v one topped up while standing. Just trying to get my head around it.
Shouldn't be a problem as I frequently do 2 x 30 mile journeys weekly. As opposed to daily before I retired.
I'm sure the big battery is isolated when the car is switched off to avoid any risk of the battery draining completely by topping up the 12V battery. If a lithium battery is left fully discharged for any significant period then it's bad for the chemistry and very expensive to replace this battery. The same also applies to the lead-acid battery but it's much cheaper to replace.
The 12V battery doesn't need to be much more than a big capacitor to serve the various components which want 12V power. There's no longer the starter motor to supply (that work is done by the big motor-generator fixed to the engine), most of the lights are LED (so no longer a pair of 60W headlight bulbs) and there are the various bits of electronics which must also benefit from the relatively stable voltage of the 12V battery compared to the fluctuations that the big battery must experience as the drive system changes modes.
However, as the OP has reported, there seems to be a situation where the 12V battery can be drained when the vehicle has been standing for a few days when it should have the capacity to supply for many weeks the residual power demands from components still alive when the vehicle is off (locking system, telemetry, ...). So far, this is a one-off event for which it would be useful to know the cause. I can't be the only person to have had one of these vehicles parked up for many weeks during the lockdowns either side of Christmas. My topping up of the 12V battery was more through habit than necessity.
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I think its all sorted now.
The CTEK was stuck on level 4 with the error light on, battery voltage 11.65V. The CTEK was not happy with the black lead connected to the chassis, after connecting to the negative battery terminal the Ctek competed its charge (green light on 8 hours later)
I have been monitoring the battery voltage and I think the problem was caused by the dealer supplying the car with only a partially charged battery.
I have ordered a voltmeter which can be left in the cigarette lighter so I can keep an eye on the battery voltage.
Thanks for all your help and advice. I liked the battery extension lead idea.
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However, if there's enough life in the 12V battery to unlock the doors and power the ECU then the big battery does the engine starting.
Interesting. On my Toyota hybrid, the 12v battery never starts the engine and you cannot jump start the car in the traditional manner. Also, the charge going into the 12v battery is at such a low current you can't charge another car from it at any kind of meaningful pace. When my Jazz battery packed in a while back there was nothing I could do for it from the RAV4, so I no longer carry jump leads in the Toyota now, pointless. I do, however, have a towing cable.
Check your Toyota handbook for safety information on a Toyota hybrid being towed "front wheels on the road rotating" for any significant distance and also the not-to-exceed speed.
I believe Toyota hybrids have to be towed front wheels off the road on a towing dolly) If towed at normal speeds with the front wheels rotating, MG2 will spin at very high rpm and be damaged.
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However, if there's enough life in the 12V battery to unlock the doors and power the ECU then the big battery does the engine starting.
Interesting. On my Toyota hybrid, the 12v battery never starts the engine and you cannot jump start the car in the traditional manner. Also, the charge going into the 12v battery is at such a low current you can't charge another car from it at any kind of meaningful pace. When my Jazz battery packed in a while back there was nothing I could do for it from the RAV4, so I no longer carry jump leads in the Toyota now, pointless. I do, however, have a towing cable.
Check your Toyota handbook for safety information on a Toyota hybrid being towed "front wheels on the road rotating" for any significant distance and also the not-to-exceed speed.
I believe Toyota hybrids have to be towed front wheels off the road on a towing dolly) If towed at normal speeds with the front wheels rotating, MG2 will spin at very high rpm and be damaged.
IIRC there is also a problem towing CVT and also EV without lifting the wheels off the road.
https://www.motorbiscuit.com/how-do-you-tow-an-electric-vehicle/
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However, if there's enough life in the 12V battery to unlock the doors and power the ECU then the big battery does the engine starting.
Interesting. On my Toyota hybrid, the 12v battery never starts the engine and you cannot jump start the car in the traditional manner. Also, the charge going into the 12v battery is at such a low current you can't charge another car from it at any kind of meaningful pace. When my Jazz battery packed in a while back there was nothing I could do for it from the RAV4, so I no longer carry jump leads in the Toyota now, pointless. I do, however, have a towing cable.
Check your Toyota handbook for safety information on a Toyota hybrid being towed "front wheels on the road rotating" for any significant distance and also the not-to-exceed speed.
I believe Toyota hybrids have to be towed front wheels off the road on a towing dolly) If towed at normal speeds with the front wheels rotating, MG2 will spin at very high rpm and be damaged.
The tow rope is for when I need to tow the Jazz for a jump start. Fully aware about towing issues for mine but thanks for the heads up. I also towed a VW Camper van to safety after the driver broke down and was parked on a bad bend.
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I think its all sorted now.
I have been monitoring the battery voltage and I think the problem was caused by the dealer supplying the car with only a partially charged battery.
Your trip home from the dealer should have provided sufficient time for the 12V battery to be fully charged.
I would keep checking the battery in case there is a problem causing an unexpected power drain.
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I have ordered a voltmeter which can be left in the cigarette lighter so I can keep an eye on the battery voltage.
I think the 12V socket is only live on a conventional car when the ignition is on, and when the engine is running the voltmeter will be showing the output voltage of the generator. If you want to monitor the condition of the 12V battery, you’d want to check the voltage after the ignition is on but before the engine is started. Not sure how that would translate to the hybrid if the 12V battery is charged from the HV system rather than directly from a generator ... is there an equivalent “ignition on” state, ie a condition of “accessory socket live but HV system not connected”?
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Yes Colin, you're right about checking the 12V battery when the car is not in "ready mode".
To do so, you need to press the power button twice without pressing the brake pedal, the cars goes into "accessory mode".
In this condition, all the car is live, except ICE and HV part (Inverter, MG etc.), so the 12V battery will not being charged, indeed, you can see the red indication of the 12V battery not being charged on the dashboard.
Whereas, if you press the brake pedal and then the power button, the car goes into "ready mode", where the HV is connected to the inverter and thus also charges the 12V battery.
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Just tested mine, yes, needs ignition on on my Civic.
Car been sitting since Monday morning:
Engine Off:
(https://i.imgur.com/Mw7Uzx5.jpg)
Engine running:
(https://i.imgur.com/68AdblR.jpg)
The unit:
(https://i.imgur.com/g3g2Ov2.jpg)
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I have been following all the discussions on the Mk4 Jazz with interest as a lot of the issues raised are also applicable to my Toyota Corolla hybrid. Flat batteries are also an issue on Toyota hybrids when they have not been used for a while. Battery capacity on my Corolla is only 45AH, but I believe from the start of this year it has gone up to 52AH. Some owners on the Toyota forum think it may be because the car can detect the key if it is nearby and the car is in some sort of standby mode. My spare key is in my bedroom but from there it is capable of unlocking / locking the car in the garage so I have now shut down the key with a few presses of the buttons as detailed in the handbook, is there a similar procedure for the Jazz key fob?
With regard to RDMS I don't think it has to be enabled to get 5 stars from NCAP. Toyotas have the same system but it is operated on/off by a button on the steering wheel. On starting the car it remembers its last position.
As a long term Jazz owner ( Mk1 & Mk2) I got into the habit of looking at this forum and still do even after transferring my allegiance to Toyota.
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My spare key is in my bedroom but from there it is capable of unlocking / locking the car in the garage so I have now shut down the key with a few presses of the buttons as detailed in the handbook, is there a similar procedure for the Jazz key fob?
For the Mk 4 Jazz hold down both buttons for several seconds and a little red LED flashes to confirm that the remote has been disabled and won't transmit any signal until a button is pressed. Even if the primary remote and/or vehicle are stored where there's no risk of a relay attack it's prudent to put the spare remote to sleep to reduce the drain on its battery.
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Since I have to park in the road, will it be ok if, from time to time, i charge the 12v battery with a solar panel connected to the OBD2 port? On Mk 4 Jazz will the OBD2 connections be correct/allow for this?
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Do I, don't I ?
Connect CTEK and give the 12V a charge or just leave it. If it can't do any harm then I'm leaning toward giving it a boost.
Reading above, connect to both terminals works OK.
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Reading above, connect to both terminals works OK.
I don't get the issue of not connecting to the negative battery post. Surely the vehicle earth/body and the battery - ve must be at the same potential.
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In the owners manual it says when jump starting to use the positive battery terminal and only an earth point near the screen wash filler - it says don’t connect it anywhere else :(
I think there is a note too about disconnecting the battery before charging, but dealers have chargers connected so it must be ok?
It means I can’t ever use my portable jump pack as the cables won’t reach that far.
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I put the 12V battery on charge several times last winter when the vehicle wasn't used for several weeks at a time. I was more concerned to keep the battery healthy than have a completely dead 12V battery immobilising the car because there's no power for the ECU. While my voltmeter reckoned the battery was down to below 12V, the charger would switch from charging to trickle in very few minutes. I connect the charger to the +ve battery terminal and to the earth strap end of the battery sensor fixed to the -ve terminal.
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Reading above, connect to both terminals works OK.
I don't get the issue of not connecting to the negative battery post. Surely the vehicle earth/body and the battery - ve must be at the same potential.
There is a current flow sensor between negative post on battery and metal of car body, by connecting the charging negative clamp directly to post you are bypassing the current flow sesnor, so you are still charging the battery but the cars computer is not registering that battery is being charged. Judging the state of charger of a battery by terminal voltage is no longer used, instead 'coulomb counting' is used, where all current flowing in and out of battery is monitored, and the computer decides if the battery is charged or not.
Even something as simple as an electric toothbrush or razor these days uses coulomb counting. I replaced the Li-ion battery on my razor, fitted a fully charged new one ( soldered in ) and turned the shaver on, the red light flashed but the razor did not rotate. I measured the terminal voltage on cell and it was something like 3.75V, so fully charged but the razor said NO... I had to unsolder the battery, use a 5watt bulb to discharge the battery down to 3.4 volts or something, solder battery back in and then charge the battery again via the proper circuitry in the shaver, and then that shaver worked fine. By putting a fully charged battery in the shaver the current sensor had not seen any power flowing into battery, so assumed that battery had no power, and would not allow motor to run even though it was fully charged.
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I'm picking up a new Crosstar from the dealer tomorrow. All this electrical stuff seems a bit daunting. The car should get frequent use, so I hope I don't have such problems.
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The main reason the Owners manual tells you to connect to the engine mount stud bolt and for this to be the last connection made is to prevent any spark being made to be away from the battery itself as a 12 volt battery gives of flammable gas, so sparking on the battery terminals itself could cause a fire/explosion.
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I'm picking up a new Crosstar from the dealer tomorrow. All this electrical stuff seems a bit daunting. The car should get frequent use, so I hope I don't have such problems.
I think these people are overthinking this. There really won’t be a problem. I don’t expect to buy a car costing over £20,000 and then worry about having to charge the 12v battery all the time! I have had my hybrid Toyota for 4 years, it is 5 years old. Never thought about this once.
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The main reason the Owners manual tells you to connect to the engine mount stud bolt and for this to be the last connection made is to prevent any spark being made to be away from the battery itself as a 12 volt battery gives of flammable gas, so sparking on the battery terminals itself could cause a fire/explosion.
No its the current flow sensor - there was a Honda tech bulletin copied somewhere on this forum that gave the reason for not connecting to battery post. Modern sealed batteries are designed not to gas, and in any case if they do gas it will only be when they are charging, not when you first attach the charger. Pretty much every battery charger made in last 10+ years is sparkless, it won't pass current until correct polarity battery voltage is sensed. In fact I have been unable to charge a battery that is in a very low state ( not enough voltage to satisfy charger sensor ) and had to connect a good battery in parallel with bad one for a while until bad battery gained sufficient voltage to convince the charger there was a battery there...
Honda tech bulletin attached ( PDF ) - it covers other things so battery charging is third page continuing on fourth page.
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The main reason the Owners manual tells you to connect to the engine mount stud bolt and for this to be the last connection made is to prevent any spark being made to be away from the battery itself as a 12 volt battery gives of flammable gas, so sparking on the battery terminals itself could cause a fire/explosion.
No its the current flow sensor - there was a Honda tech bulletin copied somewhere on this forum that gave the reason for not connecting to battery post. Modern sealed batteries are designed not to gas, and in any case if they do gas it will only be when they are charging, not when you first attach the charger. Pretty much every battery charger made in last 10+ years is sparkless, it won't pass current until correct polarity battery voltage is sensed. In fact I have been unable to charge a battery that is in a very low state ( not enough voltage to satisfy charger sensor ) and had to connect a good battery in parallel with bad one for a while until bad battery gained sufficient voltage to convince the charger there was a battery there...
Honda tech bulletin attached ( PDF ) - it covers other things so battery charging is third page continuing on fourth page.
I know the content of the bulletin, but charging and jump starting are 2 very different things and the issues involved in either.
So we will have to agree to disagree on this one, thou I suggest you find a copy of a Honda owners manual pre-battery sensor and you will find the connection orientation has always been the same.
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That's useful.
So positive to positive and I reckon CTEK negative to that protruding bolt shown better on the picture marked with the red X.
I've got hardwire ring clips that bolt on and not the crocodile clips shown. If the same as the Civic I can leave the existing nuts alone and add another on each connection.
Proper Job :)
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Another very good reason for connecting negative cable / clamp last either when connecting jumper leads or fitting a new battery is that if you connect negative first then if you touch any part of bodywork or engine with a tool while connecting the positive you have a short circuit and a big bang, same if you drop positive jumper lead onto body or engine if the negative already connected, big bang. So always connect positive first and the chances of getting a short are very low. If I was jump starting a car I would always connect straight to battery posts.
With modern maintenance free sealed valve regulated batteries used on cars and motorbikes they will only gas when being aggressively charged, and then a minute amount of gas compared to older types on non-sealed ( vented ) batteries.
Here is an extract from an article .
Practically every UPS (uninterruptible power supply) I know of has one [or more] SLA inside, so it's generally safe for indoor use. Here's a snippet from an APC white paper on the issue:
Valve regulated lead acid (VRLA) batteries [...] do not require special battery rooms and are suitable for use in an office environment. Air changes designed for human occupancy normally exceed the requirements for VRLA [...] ventilation. Vented (flooded) batteries, which release hydrogen gas continuously, require a dedicated battery room with ventilation separate from the rest of the building.
And bit later in the paper the difference in gas output is quantified as 60 times less for VRLA:
VRLA batteries are considered to be “sealed” because they normally do not allow for the addition or loss of liquid. A vented battery can give off sixty times more gas than a VRLA battery in normal use.
And the reason for this is that in a "sealed"/VRLA battery:
hydrogen recombines under pressure with oxygen into water inside the battery. Gas can only escape when internal pressure exceeds the rating of the pressure valve.
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Reading above, connect to both terminals works OK.
I don't get the issue of not connecting to the negative battery post. Surely the vehicle earth/body and the battery - ve must be at the same potential.
There is a current flow sensor between negative post on battery and metal of car body, by connecting the charging negative clamp directly to post you are bypassing the current flow sesnor, so you are still charging the battery but the cars computer is not registering that battery is being charged. Judging the state of charger of a battery by terminal voltage is no longer used, instead 'coulomb counting' is used, where all current flowing in and out of battery is monitored, and the computer decides if the battery is charged or not.
Thank you for explaining that to me.
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This is how I've done it :
(https://i.imgur.com/yFtA3k8.jpg)
All done, another job jobbed :
(https://i.imgur.com/8ISrIhz.jpg)
It took a while so 12v battery must have been fairly low.
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I haven't driven for just over 2 weeks so I decided to give it a CTEK charge yesterday.
Only took about 2½ hours to the green light so whether it's held it's charge or the smaller capacity I don't know. Civic used to take about 6 hours after a fortnight's rest.
Anyway, same as last time, the left side battery charge level was at max when I started up this morning. So I wonder what the battery meter is actually measuring ? HV/12V or a mix and match.
I plugged in my volt meter and as per a normal alternator setup it started showing 14.4v when the engine was running, then continued to show 14.4v for about a minute after the engine stopped and started dropping until it got to 12.4V
I think I'll leave it plugged in for my Saturday trip :
Image from the Civic:
(https://i.imgur.com/68AdblR.jpg)
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Those plug in Voltmeters are brilliant. I have one in the ciggy socket on the Karoq, permanently. Mine has a cabin thermometer as well. (since no car manufacturer I know of has an internal temp gauge).
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Funny you mention that, I've just ordered this :
https://www.amazon.co.uk/gp/product/B01F4RNAK0/ref=ox_sc_act_title_1?smid=A3H05HADPUYL5J&psc=1
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I had a very graphic demonstration of why it's vital to disconnect the negative (earth) lead first. Many years ago our kid disconnected the live first. Somehow he then accidentally shorted live to the body with a spanner. After a spectacular bang and flash a large chunk of the spanner (about half of a new penny, it's that long ago) had been vaporised.
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I already have the CTEK hardwire kit installed so it's just a matter of connecting a plug and switching on.
No fear of a short circuit like with crocodile clips.
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I had a very graphic demonstration of why it's vital to disconnect the negative (earth) lead first. Many years ago our kid disconnected the live first. Somehow he then accidentally shorted live to the body with a spanner. After a spectacular bang and flash a large chunk of the spanner (about half of a new penny, it's that long ago) had been vaporised.
When repairing a vehicle , it is very good practice to disconnect the battery to render the vehicle safe to work upon. I have personal experience of a short circuit in a solenoid causing an engine to self-crank without the ignition key in circuit.
The vehicle was a Honda CB250N twin, the fault was traced to the solenoid component for the starter motor, an internal short which connected the battery directly to the starter motor, had the fault occurred while the vehicle was being repaired or serviced could have caused injury to the mechanic and/or damage to the vehicle
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The battery meter on the left of the dashboard is the HV big battery - it should keep its charge for several months(maybe even a year) as it should be disconnected from anything when the car is off.
The 12V small battery will only last a few weeks before going flat - it’s just used to boot the system and connect the HV battery. From then on it’s charged by the HV battery and the HV battery is charged by the petrol engine.
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The battery meter on the left of the dashboard is the HV big battery - it should keep its charge for several months(maybe even a year) as it should be disconnected from anything when the car is off.
The recommendation in the manual is to drive the vehicle for more than 30 minutes at least once every three months, and that there is continuous drain on the HV battery.
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The recommendation in the manual is to drive the vehicle for more than 30 minutes at least once every three months, and that there is continuous drain on the HV battery.
I'd certainly like to know of anyone who's not moved the car for three months and still found the 12v. battery has enough, or any, charge left.
A brave person indeed.
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The battery meter on the left of the dashboard is the HV big battery - it should keep its charge for several months(maybe even a year) as it should be disconnected from anything when the car is off.
The recommendation in the manual is to drive the vehicle for more than 30 minutes at least once every three months, and that there is continuous drain on the HV battery.
Yes, but that is just a recommendation to avoid that the self-discharge discharge it untill it's no longer able to start the petrol engine, in the worse possibile condition, like very cold climate and car parked with 3 bars.
I'm pretty sure it will last much longer as it is a lithium battery and once the car is off, it is totally disconnected from the veichle.
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The suggestion in the manual that the 12V battery will last 3 months seems way off - I wouldn't want to leave the car for any more than 3 weeks! After 2 weeks I'd expect there's a good chance the breakdown service may be required for a jump start.
I assume the 12V battery is also the same type (AGM?) as the new stop/start batteries so permanently damaged if it's allowed to run down too low.
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I assume the 12V battery is also the same type (AGM?) as the new stop/start batteries so permanently damaged if it's allowed to run down too low.
Mk4 battery is just a standard flooded battery (Panasonic 44B19L-MF) not an EFB battery as used in Idle stop cars.
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I assume the 12V battery is also the same type (AGM?) as the new stop/start batteries so permanently damaged if it's allowed to run down too low.
Mk4 battery is just a standard flooded battery (Panasonic 44B19L-MF) not an EFB battery as used in Idle stop cars.
Thanks, that's good to know - the last battery I bought for a Volvo was £265! Someone with the same engine a few years older, before stop/start, was only paying £85 for theirs.
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The suggestion in the manual that the 12V battery will last 3 months seems way off - I wouldn't want to leave the car for any more than 3 weeks!
The three months recommendation is not the 12V battery but the high voltage lithium ion battery pack in the back.
You do not want to ever let that go flat.
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The three months recommendation is not the 12V battery but the high voltage lithium ion battery pack in the back.
You do not want to ever let that go flat.
But no mention anywhere by Honda of the 12v. battery perhaps being flat after 3 months? Interesting.
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The three months recommendation is not the 12V battery but the high voltage lithium ion battery pack in the back.
You do not want to ever let that go flat.
Yes, if it's like the Toyota ones there were only a handful of the special dealer-only chargers in the country that could attempt to recharge a HV pack after it had gone flat.
And if the charger didn't work, it was £2k+ for a new battery pack!
If you ran out of fuel, the car would run down the HV pack next until it was so low you couldn't restart the car.
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The three months recommendation is not the 12V battery but the high voltage lithium ion battery pack in the back.
You do not want to ever let that go flat.
But no mention anywhere by Honda of the 12v. battery perhaps being flat after 3 months? Interesting.
Because of this they write to drive car for 30 minutes to charge battery, they mention 12v battery that get charge from DC-DC converter, HV battery not need 30 minutes to get charged, HV battery actually can by charged up to 95% without driving car within 5 minutes.But 12v battery can’t accept big current and need more time to be charged
Our 12v battery have big self discharge rate because it’s Lead Acid battery and it’s only 35ah capacity so it discharge faster then bigger battery.
new insight have lithium ion battery (that have low self discharge rate) that placed under gear shifter in salon.
Add to this story Honda + that like I understand can woke up car computer to get information or car can check for updates through telematics.
And things can go worse if someone hardwire camera that working when car parked !!!
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Good point about dashcam parking mode although the better hardwire kits have a voltage cutoff. Not a lot of use if parking mode switches off after a few hours.
I wonder if a higher rated 12V could be fitted if needed ?
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Good point about dashcam parking mode although the better hardwire kits have a voltage cutoff. Not a lot of use if parking mode switches off after a few hours.
I wonder if a higher rated 12V could be fitted if needed ?
Best solution to use small additional battery like those that used by BlackView BlackVue B-112 Power Magic Battery Pack
or one from Thinkware https://us.thinkware.com/product-page/external-battery-bab-50-hardwired/ (https://us.thinkware.com/product-page/external-battery-bab-50-hardwired/)
https://ca.thinkware.com/thinkware-ivolt-mini-ultimate-guide/ (https://ca.thinkware.com/thinkware-ivolt-mini-ultimate-guide/) explanation and instalation how to
that option cost $ but the auxilary 12v car battery will not by discharged because camera hardwired to this backup battery and backup battery get energy from car 12v system only when car in ready mode.
This backup batery can by diy one with safer chemistry cells (NiMH for example - robot vacuum packs can by adopted if they 12v - 10 cells) but this pack will have bigger weight.
with DIY battery only problem to get camera sense that ignition switched off. otherwice it may not use parking mode.
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Good point about dashcam parking mode although the better hardwire kits have a voltage cutoff. Not a lot of use if parking mode switches off after a few hours.
I wonder if a higher rated 12V could be fitted if needed ?
Best solution to use small additional battery like those that used by BlackView BlackVue B-112 Power Magic Battery Pack
or one from Thinkware https://us.thinkware.com/product-page/external-battery-bab-50-hardwired/ (https://us.thinkware.com/product-page/external-battery-bab-50-hardwired/)
https://ca.thinkware.com/thinkware-ivolt-mini-ultimate-guide/ (https://ca.thinkware.com/thinkware-ivolt-mini-ultimate-guide/) explanation and instalation how to
that option cost $ but the auxilary 12v car battery will not by discharged because camera hardwired to this backup battery and backup battery get energy from car 12v system only when car in ready mode.
This backup batery can by diy one with safer chemistry cells (NiMH for example - robot vacuum packs can by adopted if they 12v - 10 cells) but this pack will have bigger weight.
with DIY battery only problem to get camera sense that ignition switched off. otherwice it may not use parking mode.
Don't the dashcams have the normal 5volt micro or mini USB socket ? The 12 volt power supply that plugs into car cigarette lighter aka accessory socket just steps the 12v down to 5 volts. I believe Jocko fitted a 10,000mA/h like this into circuit with his NextBase dashcam, when the cigarette socket was powered up it charged the powerpack and when off the powerpack powered the dashcam, as said above the Li-Ion battery cannot backfeed into car electrics when ignition off because 12v accessory socket is isolated from car electrics.
A dashcam will normally draw about 1.5 watts at 5 volts = about 0.030 amps, so the 10A/h battery will last a decent time - if a dashcam has a separate supply for 'parking mode' it means that only the 'G' sensor is powered and if it gets activated the camera will begin recording for a set length of time, the power required in that mode will be very, very small... obviously it would take a while to drain a car battery, but some power is wasted in the 12v -> 5volt power supply which would not be wasted by the 5v battery pack direct to dashcam ( if the 12volt accessory plug gets warm, that is wasted power ).
https://www.amazon.co.uk/10000mAh-Portable-Charger-Battery-compatible/dp/B09CR6JDZP/ref=sr_1_10?dchild=1&keywords=5v+battery+pack&qid=1633079129&sr=8-10
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I believe Jocko fitted a 10,000mA/h like this into circuit with his NextBase dashcam, when the cigarette socket was powered up it charged the powerpack and when off the powerpack powered the dashcam, as said above the Li-Ion battery cannot backfeed into car electrics when ignition off because 12v accessory socket is isolated from car electrics.
That sounds like a good system.
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When you doing hardwire connection of dashcam you using 12v adapter that compatible with your dashcam this hardwire kit can tell to dashcam when to go to parking monitor mode, this adapter have dc-dc converter inside and low voltage disconnect logic.
But some dashcams connects to 12v and have all electronics to convert voltage inside.
Yes some cameras can go in parking monitor mode without hardwire kit by using vibration sensor.
I tried option with powerbank but that not worked good with dashcam that i used (used 4k dashcam Viofo A129Pro Duo)
Avoid this dashcam it`s bugy stopping write overheating stopping respond, sometimes with baddly assembled optic so you have part of image out of focus !!! and also they hardware kit - they work very bad cut of voltage not ajusted when you set 11.9v this module not dissconnected dashcam when reaching 11.9v.
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Correct
There are 2 main systems :
The first system uses a 2 wire kit and just relies on no car movement for a set period to go into parking mode. This requires the kit to be wired to permanent live.
The second system has a 3 wire kit, one wire to permanent live and the other to an IGN source. Turning off the car ignition puts it into instant parking mode.
As well as here I also keep an eye on DashcamTalk and from what I read no parking mode system is without glitches.
I've got my Viofo wired via a Nextbase 2 wire kit just wired to IGN so the dashcam fires up and shuts down with IGN power. I don't need parking mode as it's garaged.
It sounds like what Jocko did was put a powerbank into the equation which is one solution but that means the dashcam is powered up 24x7 unless it's one that shuts down with no movement. If that's the case then upon movement it fires up and may be too late to capture what you need.
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I haven't read this thread in detail, but just as a note of caution, typical plug-in 12V to USB adapters take significant current even when nothing is plugged into them. Someone I know had one on a motorbike and it kept flattening the battery, I measured the no-load current at about 25-30mA (effectively drain a typical service 10Ah bike battery in around 10days so the bike won't start). Not much of a problem with a regularly used 45Ah car battery, but smaller back-up ones could be an issue.
Note just to be aware.
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Correct
There are 2 main systems :
The first system uses a 2 wire kit and just relies on no car movement for a set period to go into parking mode. This requires the kit to be wired to permanent live.
The second system has a 3 wire kit, one wire to permanent live and the other to an IGN source. Turning off the car ignition puts it into instant parking mode.
As well as here I also keep an eye on DashcamTalk and from what I read no parking mode system is without glitches.
I've got my Viofo wired via a Nextbase 2 wire kit just wired to IGN so the dashcam fires up and shuts down with IGN power. I don't need parking mode as it's garaged.
It sounds like what Jocko did was put a powerbank into the equation which is one solution but that means the dashcam is powered up 24x7 unless it's one that shuts down with no movement. If that's the case then upon movement it fires up and may be too late to capture what you need.
IIRC Jocko said it was powered up all the time so taking video until the powerbank conked out, but if G sensor does get activated it will save the present clip ( probably 3 minutes ) to a locked file, so easier to find. I found G sensor really sensitive on my NextBase 511GW and had to basically turn it off because I was getting too many locked files from even slight bumps in the road. If you only use the powerbank when parked in public places and not on your own driveway it would be fine.
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I seem to recall a Jocko YT post and I'm sure he also has a Nextbase.
I'm sure Nextbase units go to sleep after a few minutes of no detected movement hence why the Nextbase hardwire kit is only 2 wires.
TBH I'm not sure I'd be happy with it recording 24x7 unless like some units it drops back to timelapse. Also, from what I've read, constant loop recording to SDCards, overwrite oldest, severely shortens their life. Something to do with NAND.