Clubjazz - Honda Jazz & HR-V Forums
Honda Jazz Forums => Honda Jazz Mk3 2015-2020 => Topic started by: ColinB on February 08, 2017, 04:58:56 PM
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My car's idle-stop system system seems to have stopped working for no apparent reason. I was putting it down to the cold weather (the handbook mentions several temperature-related factors that would inhibit it). But then I found this thread over on the HRV forums (with contributions from people who post to this forum as well):
http://www.hrvforums.co.uk/viewtopic.php?f=11&t=289 (http://www.hrvforums.co.uk/viewtopic.php?f=11&t=289)
My symptoms are exactly as described there, i.e. in circumstances where the idle-stop used to work I now get the circled-A-with-a-line-through-it, sometimes accompanied by the low-battery symbol, and the engine keeps running. That's even after a longish journey to warm the engine and cabin properly and charge the battery. Ambient temperature here today was between 5 & 7 degrees.
Doesn't stop me using the car, and some people might think that finding a way to turn it off permanently is useful, but it's niggling.
Anyone else seeing anything like this ? Or conversely please post to confirm if your idle-stop is working perfectly in current temperatures.
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My stop start is working as it should. I have had a couple of "Not working, low battery" indications which I take as the car knows what is going on and all is well. Car batteries have a tough time during winter, I charge mine most weekends during the winter with a 5amp CTEK smart charger and it is surprising how long it can take to fully charge. The cars user manual recommends charging the battery occasionally.
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Yup, me too. It is still working but it's often displaying '
A/C' where previously it wouldn't. I do have my vents set to 'foot and screen' but they've been that way a while and it's only in the last month or so that SS has been blocked by my aircon. Just seems that the A/C (or some part of the ventilation) is working hard.
This morning when I got to Banbury (after a fifteen minute run at fairly steady 50mph) I stopped at the M40 lights and..'A/C'. But at the next set of lights (blasted pedestrians, how dare they ;D) it cut the engine as it should. Ten minutes later at my office gates..'A/C'.
My fan is on higher for longer at the moment on startup but it has gone back down to it's normal two bars by the time I get to Banbury of a morning.
I've never had it show the low battery symbol though.
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From looking more carefully this morning I think mind is refusing to idle stop if the fan is on three bars are higher. It seems that on cold mornings it eventually settles down to alternating between two and three bars.
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When I was first getting used to how the idle-stop thingy worked, I noticed that the "A/C" indication on the multi-display had nothing to do with A/C. I have the manual ventilation system so I control the vent position, fan speed, and A/C separately. I saw that the idle-stop worked when I had the A/C running, but not when I had the vent position set to screen only irrespective of whether the A/C was switched on or not. So my conclusion was that "A/C" on the multi-display was Honda's way of telling you that idle-stop won't work if the car thinks you're trying to defrost or demist the screen. Some similar sort of logic may be happening with Climate Control. But the list of reasons why it might not work is so complex that it's almost impossible to work out what might be happening in any specific circumstances.
Regarding my original Q, it looks like it's only me (thanks for the input) so I'll need to investigate further. I'll try some battery voltage checks and taking the car for a really long run to charge it fully.
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I have the H-RV and experience all the same issues. To be honest, I have stopped obsessing on whether the Stop/Start system is broken or not. I know it works, I just don't know when it works and I am no longer bothered. I think the software that decides whether to stop the engine or not was written in by someone who does not drive on busy UK roads with our mix of weather and short/long journeys with batteries which may or may not be fully charged. There are too many variables to second guess the system so I have given up trying.
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As far as I can tell mine is working within the design parameters of when the auto stop is not available, which as far as I can tell are:
• The vehicle did not exceeded 3 KM/H (2 MPH) before coming to a stop.
• Reverse gear has been selected.
• Humidity in car is too high.
• The steering wheel has been turned.
• The engine temperature either too high or too low.
• The climate control temperature is set to maximum hot (Hi) or minimum cold (Lo)
• Mode is set to screen defrost/demist.
• If the actual cabin temperature and the set temperature on the climate unit is too great the climate control unit not will permit auto stop function.
• The Higher the fan speed is set to can also have an influence on Auto Stop function
• Battery or charging error.
• Incorrect battery fitted to the vehicle (non auto stop battery).
Correct me if I am wrong but I think one or more of these will account for the situations you all describe.
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As far as I can tell mine is working within the design parameters of when the auto stop is not available, which as far as I can tell are:
• The vehicle did not exceeded 3 KM/H (2 MPH) before coming to a stop.
• Reverse gear has been selected.
• Humidity in car is too high.
• The steering wheel has been turned.
• The engine temperature either too high or too low.
• The climate control temperature is set to maximum hot (Hi) or minimum cold (Lo)
• Mode is set to screen defrost/demist.
• If the actual cabin temperature and the set temperature on the climate unit is too great the climate control unit not will permit auto stop function.
• The Higher the fan speed is set to can also have an influence on Auto Stop function
• Battery or charging error.
• Incorrect battery fitted to the vehicle (non auto stop battery).
Correct me if I am wrong but I think one or more of these will account for the situations you all describe.
That's as maybe, all I can say is that I am driving the car exactly the same as before and in situations where it used to work it doesn't. The obvious factor is the cold weather but if others are finding it works in current ambient temperatures then that's probably unlikely as a cause. So the worrying one on your list is the penultimate one which - if that's the cause - is something I'd want to do something about.
I have the H-RV and experience all the same issues. To be honest, I have stopped obsessing on whether the Stop/Start system is broken or not. I know it works, I just don't know when it works and I am no longer bothered. I think the software that decides whether to stop the engine or not was written in by someone who does not drive on busy UK roads with our mix of weather and short/long journeys with batteries which may or may not be fully charged. There are too many variables to second guess the system so I have given up trying.
Richard, thanks for this, I noticed your contributions over in the HRV forum. I agree it's probably not worth worrying about in itself, I just want to ensure it's not a symptom of something more serious.
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So the worrying one on your list is the penultimate one which - if that's the cause - is something I'd want to do something about.
Unfortunately that does look likely Colin. Hope the list was of some use.
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Richard, thanks for this, I noticed your contributions over in the HRV forum. I agree it's probably not worth worrying about in itself, I just want to ensure it's not a symptom of something more serious.
I agree, but I have concluded that it isn't. I am a software engineer and I think some of the software in our H-RVs (and presumably Jazzes) is just too complicated. And ColinS' list above of all the things that could affect the Stop/Start makes that abundantly clear.
To be honest, most of the time the thing does engage, it's hardly worth it, as I am usually only stopped for a few seconds. When you want it to kick in is when you have pulled up at the lights at the start of a long sequence or when you are at roadworks or a motorway holdup, and you don't want to turn off the ignition as you would lose the radio, sat nav, heated seat setting, auto hold setting etc..
What I would like is something more nuanced than an on/off button for Stop/Start. For example, if Stop/Start is on, I might want to override it for a few moments rather than turn it off completely. Or I might want to force an engine stop but not turn off at the ignition - i.e. a driver selected stop/start, to keep all my settings active.
I think I am just going to turn the thing off though as I am convinced that for my personal driving situation, it adds no value and saves no fuel.
P.S. ColinS, where did you get your list from? Is that publicly available? Is it somewhere in the Handbook?
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I think I am just going to turn the thing off though as I am convinced that for my personal driving situation, it adds no value and saves no fuel.
I agree, difficult to believe that it saves much fuel, but I can believe it might improve urban pollution in high traffic areas if lots of cars are doing it.
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P.S. ColinS, where did you get your list from? Is that publicly available? Is it somewhere in the Handbook?
I simplified an article from another website https://hondakarma.com/ (https://hondakarma.com/) but there is an extensive list on pages 406-407 of the manual which includes some other more obscure things such as altitude, being stopped on a steep incline and the driver's seat belt not being fastened.
I'm sure they were all put in there for good reason, either to save the battery or for safety, but I tend to agree with you that it is all a bit complicated and, as we know, complicated things are more prone to failure. I also believe if some of them were not in there, then people would complain about that.
I like your idea of a manual idle stop button.
The one other item in the list that ColinB may consider is "The capacitor unit condition is not good" (Page 406).
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I have the theory that the system checks the battery health when the engine is started by looking at the voltage across the starter motor. It may then make assumptions about how much charge is being put in or it may just decide that the battery is too low to allow auto stop to be used on that journey. I developed this theory when I went on a 100 mile mainly motorway journey after the Jazz had been standing for a couple of weeks and auto stop didn't want to work after 80 miles of motorway on what was a nice day (so no competition for power from the alternator). Once the car had been stopped and restarted the auto stop was fine.
If this theory is correct and the voltage is measured away from the battery itself then any slightly poor connections which create a voltage drop will be interpreted as a lower voltage at the battery. Check the connections on the battery itself. However, there is also the underlying suspicion that Honda might have skimped on the alternator capacity which struggles to meet the needs of European winter driving, particularly for shortish trips. The Mk 3 also seems to have a higher rate of battery self discharge than its predecessors. Perhaps more electronics which don't turn off are slowly leaking power when the car is stopped. A built-in solar panel would help keep the battery healthy (except for the vehicles stored under a roof).
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I think I am just going to turn the thing off though as I am convinced that for my personal driving situation, it adds no value and saves no fuel.
I agree, difficult to believe that it saves much fuel, but I can believe it might improve urban pollution in high traffic areas if lots of cars are doing it.
Various tests of various manufacturers of cars suggest it can save between 5% and 10%. The same tests suggest that the break-even point is around two seconds. Any less than that and the cost of restarting is greater than the fuel saved.
I'd suggest though that rather than turning the feature off maybe people could just learn to work with it. The strategies below don't just help you manage idle-stop - they also make you a more efficient and safer driver.
Better anticipation of traffic flow should allow you to choose whether to come to a stop or slow right down instead. In stop/start traffic there's nothing to be gained from hanging off the rear bumper of the car in front. Instead of accelerator/brake/accelerator/brake/... try and find a crawling speed and gap size that allows you to just bimble along at a few mph.
If you're approaching the end of a queue you might as well slow down early. Time it right and you might never have to stop. If driving through a serious of roundabouts don't do it at top speed. Slow down a bit to give traffic waiting to enter ahead of you time to dissipate. Do it right and you might get through the entire run without stopping. Doing this you'll save fuel and reduce brake wear.
If you have no choice but to stop and you think it likely it will be for less than two seconds then moderate the pressure on the break pedal you can use enough to hold the vehicle but not enough to activate idle-stop.
It's all about driver skill and knowing how to operate your vehicle. ;)
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Various tests of various manufacturers of cars suggest it can save between 5% and 10%.
That is a very big number, which is failing my BS test ;)
Maybe the explanation is in the definition/calculation of "5-10%"...can you give any links to help understand.
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I'd suggest though that rather than turning the feature off maybe people could just learn to work with it.
If it's all the same to you, I think I'll just turn it off. One less thing to distract me.
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I'd suggest though that rather than turning the feature off maybe people could just learn to work with it.
If it's all the same to you, I think I'll just turn it off. One less thing to distract me.
I agree with your earlier posts, not worth worrying about. Most of the time it works fine and predictably, very occasionally it is not available for no obvious reason. Either way I don't find it a distraction, and the point mentioned earlier about light and firm pressure is intuitive.
Note I am pretty sure you can only turn it off per journey....the off setting by the gear lever is re-set each journey.
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Various tests of various manufacturers of cars suggest it can save between 5% and 10%.
That is a very big number, which is failing my BS test ;)
Maybe the explanation is in the definition/calculation of "5-10%"...can you give any links to help understand.
http://www.nrcan.gc.ca/energy/efficiency/transportation/cars-light-trucks/buying/16757 (http://www.nrcan.gc.ca/energy/efficiency/transportation/cars-light-trucks/buying/16757)
http://www.consumerreports.org/cro/news/2012/06/stop-idling-stop-start-systems-have-great-promise-for-saving-fuel/index.htm (http://www.consumerreports.org/cro/news/2012/06/stop-idling-stop-start-systems-have-great-promise-for-saving-fuel/index.htm)
https://www.edmunds.com/car-reviews/features/do-stop-start-systems-really-save-fuel.html (https://www.edmunds.com/car-reviews/features/do-stop-start-systems-really-save-fuel.html)
It is of course going to vary depending on the type of journey. For a 200 mile motorway drive idle-stop is not going to save you anything. But for a vehicle used for the school-run or commuting the savings could be quite significant. I've seen the difference. Last year Southam Road in Banbury (a primary access route) was being dug up. If I got caught by the lights - which were a long cycle - I'd be sitting there for a minute with the fuel readout fixed. When the idle-stop finally gave up and switched the engine back on I could see the mpg figure dropping by a tenth every 20 seconds. Catching those lights at the worst possible time would 'cost me' nearly .4mpg according to the display.
https://www.quora.com/How-much-gas-does-a-car-burn-per-hour-while-idling (https://www.quora.com/How-much-gas-does-a-car-burn-per-hour-while-idling)
"0.02 L/min"
So if I'm stationary for two minutes on my daily commute each way (reasonable) that's nearly 0.1 litres of fuel that could be saved. My entire commute is 12 miles each way which is about 2.5 litres in total. So I'm not far off that 5% saving. Now in truth my commute is mostly rural so 9 miles of it won't benefit from idle-stop anyway. For someone with a shorter commute or more horrible urban experience than my 2 miles of Banbury the savings would be a lot higher.
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Various tests of various manufacturers of cars suggest it can save between 5% and 10%.
That is a very big number, which is failing my BS test ;)
Maybe the explanation is in the definition/calculation of "5-10%"...can you give any links to help understand.
http://www.nrcan.gc.ca/energy/efficiency/transportation/cars-light-trucks/buying/16757 (http://www.nrcan.gc.ca/energy/efficiency/transportation/cars-light-trucks/buying/16757)
http://www.consumerreports.org/cro/news/2012/06/stop-idling-stop-start-systems-have-great-promise-for-saving-fuel/index.htm (http://www.consumerreports.org/cro/news/2012/06/stop-idling-stop-start-systems-have-great-promise-for-saving-fuel/index.htm)
https://www.edmunds.com/car-reviews/features/do-stop-start-systems-really-save-fuel.html (https://www.edmunds.com/car-reviews/features/do-stop-start-systems-really-save-fuel.html)
It is of course going to vary depending on the type of journey. For a 200 mile motorway drive idle-stop is not going to save you anything. But for a vehicle used for the school-run or commuting the savings could be quite significant. I've seen the difference. Last year Southam Road in Banbury (a primary access route) was being dug up. If I got caught by the lights - which were a long cycle - I'd be sitting there for a minute with the fuel readout fixed. When the idle-stop finally gave up and switched the engine back on I could see the mpg figure dropping by a tenth every 20 seconds. Catching those lights at the worst possible time would 'cost me' nearly .4mpg according to the display.
https://www.quora.com/How-much-gas-does-a-car-burn-per-hour-while-idling (https://www.quora.com/How-much-gas-does-a-car-burn-per-hour-while-idling)
"0.02 L/min"
So if I'm stationary for two minutes on my daily commute each way (reasonable) that's nearly 0.1 litres of fuel that could be saved. My entire commute is 12 miles each way which is about 2.5 litres in total. So I'm not far off that 5% saving. Now in truth my commute is mostly rural so 9 miles of it won't benefit from idle-stop anyway. For someone with a shorter commute or more horrible urban experience than my 2 miles of Banbury the savings would be a lot higher.
Thanks! very interesting.
The first three links all said they had measured in city driving, rather than averaged out over a motorway/rural/city mix which makes the 5-10% more credible.
Your numbers are interesting. I thought 0.01L/min was nearer the average of the answers in that link than .02L/min, assuming they are talking US gals. This gives lower than 5% for your mixed rural/city commute but probably consistent with 5% for a city cycle.
So bottom line of my nit-picking is I'll buy 5-10% saving in city driving.
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Fascinating discussion, but if I may go back to the original issue.
Regarding my original Q, it looks like it's only me (thanks for the input) so I'll need to investigate further. I'll try some battery voltage checks and taking the car for a really long run to charge it fully.
So today I dug out my multimeter, which (at various times) gave voltages across the battery between 12.5 and 12.7 with the engine stopped and 14.25 with the engine running. Ambient temperature throughout was between 2 & 3 degrees. That all sounds fine to me, so the battery itself and the charging system seem OK (?)
I've also done a run totalling 80 miles: 40 each way, with a pause in the middle to check voltages and give the car a chance to start anew as per John Ratsey's suggestion: idle-stop didn't function at any time. The multi-display messages varied, sometimes it was just the circled-A-with-a-line-through-it, sometimes it had the low battery indication as well. At the end of the run I got the "low battery" indication, but yet measured the battery voltage at 12.7V.
Called my local dealer, who immediately knew what I was talking about because they've seen it before and have had to "reset the system" (whatever that means) on other cars. So I'm booked in for that ... although not until 1st March because (apparently) they are "snowed under with airbag recall work".
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I thought it's main purpose was to boost the fuel consumption figures during the official testing.
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I thought it's main purpose was to boost the fuel consumption figures during the official testing.
:D :D
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I think the urban test is where the 5 to 10% comes from.
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because (apparently) they are "snowed under with airbag recall work".
Well, that's made me feel a whole lot safer :o
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Called my local dealer, who immediately knew what I was talking about because they've seen it before and have had to "reset the system" (whatever that means) on other cars. So I'm booked in for that ... although not until 1st March because (apparently) they are "snowed under with airbag recall work".
Somewhere (my HR-V manual?) I read that the reset involves disconnecting / reconnecting the batttery. I did that on my HR-V (which is when I discovered that the earth cable wasn't very tight on the battery terminal)http://www.hrvforums.co.uk/viewtopic.php?f=11&t=289&start=30#p2849] [url]http://www.hrvforums.co.uk/viewtopic.php?f=11&t=289&start=30#p2849 (http://[url)[/url]. One/both of disconnecting and then tightening the clamp properly got the auto stop working. Note that the radio loses its code and briefly complains when you turn the ignition key but it then finds that the code is stored somewhere. If you can't find something similar in the Jazz manual then I'll search the HR-V manual for the relevant info.
Also make sure that all the electrical connections are tight. A resistance of 0.01 ohms will cause a voltage drop of 1V if the starter motor pulls 100 Amps.
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I believe the airbag problem is a historic one affecting many car manufacturers. The UK Jazz is too young to be affected.
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The airbag problem is a current one and cars, including the Jazz, are being booked in now for the work to be done as spare parts are now available.
There is plenty on this forum on the subject.
Vic.
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Are any of the Mk3s affected? I should have specified the GK model, older ones could be affected. I have just checked mine on the Honda UK recall check website and it has no recalls.
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I checked my Mk 2 2011 model not long ago which said that no recalls were outstanding.
A couple of weeks ago I got an email asking me to book my car in for the airbag job !
Vic.
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It seems that only cars built before 2015 a affected. They must be recalling them in batches.
http://www.whatcar.com/news/biggest-ever-car-recall-sparked-by-airbag-fault/ (http://www.whatcar.com/news/biggest-ever-car-recall-sparked-by-airbag-fault/)
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Our ex-family fleet Alfa would not auto stop unless the steering was exactly straight ahead, I assume this was to assist with joining a fast road from a side road.
... and Honda have been building cars with 'recallable' airbags while performing recalls of older cars first due to limited production capacity at suppliers.
--
TG
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9 degrees centigrade, and after a 20 mile run in sunshine with no Air con the auto stop still doesn't operate, showing the battery symbol. Perhaps it's a Russian cyberattack!
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9 degrees centigrade, and after a 20 mile run in sunshine with no Air con the auto stop still doesn't operate, showing the battery symbol.
That's pretty similar to what I'm seeing. Although it has actually improved, instead of not working at all, it now functions maybe 10-20% of the occasions when I expect it to.
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9 degrees centigrade, and after a 20 mile run in sunshine with no Air con the auto stop still doesn't operate, showing the battery symbol. Perhaps it's a Russian cyberattack!
The first journey may charge the battery but my hypothesis is that car won't realise that the battery is now fully charged until the next journey as I think it checks the charge status when the engine is started.
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My car is used daily, a mixture of local pottering and at least 30 minutes motorway or NSL roads two or three times a week. I have only seen the low battery indication for no stop start a couple of times. I charge my battery most weekends during cold weather, it can take surprising length of time to fully charge with a variable rate smart charger with maximum of 5 amps.
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Mine definitely relates to the fan. If it's on three or more bars the I/S won't operate. I assume that once the weather warms up a bit the climate control won't need the fan on so high for so long and I/S will start operating more frequently.
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None of those suggestions would seem to account for a mix of working and not working with a low battery indication in the course of a single journey. Fan on 1 or 2, vent switch NOT set to demist screen. Nor why a battery with a measured voltage of 12.7V produces a low battery warning.
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If it is any help, my car has done a 20 mile round trip this morning, and a ten minute local potter this afternoon. My manual air con has been off with the fan on position 2 throughout. The stop start is working perfectly. I have just checked my battery voltage, it is 12.6V. The battery has not been on a charger for over a week.
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Turns out it's not the fan speed. I/S was working just fine tonight with the fan on 3. It is milder and drier tonight though.
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Turns out it's not the fan speed. I/S was working just fine tonight with the fan on 3. It is milder and drier tonight though.
That makes sense, the alternator sustains the cars electrical load and charges the battery with any spare output. I would be surprised if the alternator has less than about 80amps output.
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Turns out it's not the fan speed. I/S was working just fine tonight with the fan on 3. It is milder and drier tonight though.
That makes sense, the alternator sustains the cars electrical load and charges the battery with any spare output. I would be surprised if the alternator has less than about 80amps output.
So the mystery is what was my climate control doing this morning when it was 3 degrees, and I'd driven over 8 miles at 50mph, that it wasn't doing this evening at 10 degrees when I'd only driven a mile or so in rush hour traffic ???
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Anybody's guess what your climate control was up to, the cars computers will know, but I think you are making the mistake of trying to pin down one reason for the stop start not activating. I know that one of my previous cars had about 15 parameters that had to be met for the stop start to activate. The heated rear window was one thing which would deactivate it. There is a post up thread somewhere about the multitude of things that deactivate it. These days the car knows more about its operating procedures than the owner, let it do its own thing. You will know when it is broken, the wheels will not go round. :-)
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These days the car knows more about its operating procedures than the owner, let it do its own thing.
Sorry. You're talking to a computer programmer. 'Let it do it's own thing' is not a concept I can be happy with ;)
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These days the car knows more about its operating procedures than the owner, let it do its own thing.
Sorry. You're talking to a computer programmer. 'Let it do it's own thing' is not a concept I can be happy with ;)
Ok, take the computer to bits and find out what it is doing, or get the specifications and programs for the cars computers. As an IT expert you should know better than trying to guess what a computer or three are doing. :-)
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These days the car knows more about its operating procedures than the owner, let it do its own thing. You will know when it is broken, the wheels will not go round. :-)
Only up to a point. Personally I don't like a car that isn't behaving predictably, because if it isn't that can be an early indication of a fault that I want to get fixed before the wheels stop turning. After nearly 18 months of driving it I know where, on my usual trips, I can expect the I/S to function and in general it's done that. Now, for no apparent reason, it's not doing that so I want to know why.
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The car is controlled by several computers, you are no longer master of the cars controls. The knobs and switches only ask a computer to carry out your request. For various reasons it might refuse, low battery is the obvious one as the computers will prioritise essential functions. The stop start, climate control, auto lights, auto wipers, and wiper / lights link are good examples of the car deciding what is best regardless of what you the driver thinks.
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Another thought, there are fault lights on many of the cars systems, so the instrument panel will light up like a Christmas tree if the car thinks it is broken. Some more car thinks it knows best ones that the driver has little or no control over are city braking, anti skid, traction control, hill start assist, and abs. The engine ecu monitors the engine and optimises its operation many times a second, people don't complain about that. :-)
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Don't any of you computer experts disagree with my version of events? :-)
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I have just stumbled across this, it may help the people puzzled by their cars electrical antics. I have no idea if Honda uses this technology but it is an indication of the way things are going. It covers stop start.
http://www.batterypoweronline.com/main/articles/battery-management-with-an-intelligent-battery-sensor-is-vital-to-the-success-of-future-automotive-designs/ (http://www.batterypoweronline.com/main/articles/battery-management-with-an-intelligent-battery-sensor-is-vital-to-the-success-of-future-automotive-designs/)
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Argggh, having just looked there is a small black plastic box on the Jazz battery negative post with three thin wires disappearing into the wiring loom, I now wonder if it is one of these IBS devices.
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I now wonder if it is one of these IBS devices.
Irritable Bowel Syndrome?
;D
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In some peoples case it is Irritating Battery System. :-)
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I would like to know the effect of stop-start on turbo engines, where turbo can be damaged if not cooled by spooling down, if you come from speed to a stop in traffic and engine cuts out straight away heat transfers from 'hot' side into bearings, cooking the oil. Also affect of stop start on bearing life - if bearings keep losing their pressurised oil supply which keeps the metal surfaces apart, I know car makers say they have new materials in the bearings but don't know how well proven they are in real life service.
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I think the introduction of fully synthetic oils used in most cars these days have solved heat related turbo issues, unless you are driving a fully laden car and caravan up a mountain and stop to admire the view at the top. I have never seen a car with a turbo problem in a motorway service area or anywhere else. I drove them (admittedly diesels) for over 30 years without a problem or any cool down. Is turbo failure a big problem in petrol cars?
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Is turbo failure a big problem in petrol cars?
Not really a problem for the Jazz ;D
Getting back to the original posting, I started this thread because I was noticing odd behaviour from my car's Idle-Stop (I/S) system and wondered why that might be. I'm now seeing it back to normal again. So same car, same driver, same driving style, same routes, same traffic lights, and the engine now stops when I expect it to. There's been no system reset, or removal/replacement of battery connections, or additional battery charging. The obvious variable still seems to be the ambient temperature, it's now nearly 10 degrees warmer than previously.
The handbook mentions various temperature-related factors that may prevent I/S operation including esoteric measurements like low battery internal temperature (does that need the IBS mentioned previously ?). I thought that the battery would get warmed just by being in the engine compartment, but maybe not enough. So I'm theorising that the low-battery indication may actually be a symptom of low battery temperature (which may of course show up as low voltage), in much the same way that the A/C indication is actually a symptom of the vent position control being on full screen and is nothing to do with the A/C.
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It's that little black box on your batteries negative terminal. Even if it Is only a sensor. I think you are on a loser trying to outguess a modern cars electronics.
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I think you are on a loser trying to outguess a modern cars electronics.
I disagree. If a computerised machine starts behaving differently to previously, and throws in something that looks like a spurious fault indication as well (i.e. a low battery indication on a fully-charged battery) then that to me is something worth trying to understand. It's called curiosity, and it might conceivably have been an early indication of a fault with the battery or the charging system (that is after all what the handbook suggests). Nor do I agree with your thesis that the computer is always right, and neither it nor its various auxiliary sensors can possibly go wrong. They can and do: no machine - not even a Honda - is that perfect.
We obviously have different opinions about this, and you are of course entitled to yours even if I disagree. So let's agree to respect those opinions and continue to enjoy some lively and informative discussions.
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It was curiosity that led me to the IBS device, if your battery is not charging the warning light should come on or alternatively very soon your car will not start. You will not be left in any doubt. :-)
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It was curiosity that led me to the IBS device, if your battery is not charging the warning light should come on or alternatively very soon your car will not start. You will not be left in any doubt. :-)
Thanks for that useful link to the IBS. I noted with interest that it monitors the battery temperature as well as the charge / discharge rate. I'm therefore wondering whether Honda have programmed a minimum battery temperature (eg 10C?) into the software. On a very cold day it will take a while for the battery to warm up to the threshold temperature and if the battery is too cold then the system will report low battery when the real problem is cold battery which could explain the behaviour we are seeing. Cars should have thermostatically controlled louvres on the radiator grille to help get the engine compartment up to a suitable working temperature as quickly as possible.
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Cars should have thermostatically controlled louvres on the radiator grille to help get the engine compartment up to a suitable working temperature as quickly as possible.
Do you remember the days when cars had external muffs to keep the radiator warm when driving in sub-zero temperatures?
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Cars should have thermostatically controlled louvres on the radiator grille to help get the engine compartment up to a suitable working temperature as quickly as possible.
Do you remember the days when cars had external muffs to keep the radiator warm when driving in sub-zero temperatures?
Yes, but my cars have all had thermostats. :-)
I think John might be onto something, a cold battery may give the same symptoms as a less than fully charged one. Maybe there is a bit of both going on. A cold 75% charged battery might start to be protected by the cars systems. The same may be true for a hot battery, soon after I bought my car it auto started after I had been stopped in traffic for about five minutes and gave a low battery warning. I remember it was a hot day.
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Do you remember the days when cars had external muffs to keep the radiator warm when driving in sub-zero temperatures?
I remember hanging a plastic sack between the radiator grille and the radiator of my A35 during the winter months, if that counts. It was easily accessible. Anyway, getting back on topic, the measurement of battery temperature might explain why the idle stop tends to be more reluctant to work during cold weather.
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I now suspect that the battery management is an infinitely variable blend of battery charge level, charge rate, load, and temperature. Good luck with expecting consistent or predictable performance from your cars electrical systems. :-)