Honda Jazz Mk4 12v battery "upgrade"?

[1speed]

I have a 2023 Advance with 3000ish on it, due to my bad habit of listening to the radio for 15 minutes everyday while in accessory mode I've started having battery and starting issues, occasionally after driving the car and leaving it parked for a few hours the system would start giving warnings about everything, brakes, lane assist etc. and only start after repeated power up and downs, after which it will start normally without any warning.

All this led me to think I've ruined the tiny 12v battery, since we know when voltage drops below a certain level the sensors and system will stop working properly, also the issue reoccurrs every few weeks even though I've stopped using the radio in accessory mode, reduced usage while driving and turn off the screen when driving.

I park in the street and have no way of charging other than removing the battery, therefore leaving possible computer problems aside, I'm thinking of replacing the 12v battery.

Has anybody swapped the 12v battery to a bigger one like for the older Jazz versions? Will this void the warranty?

[Kremmen]

As I've just posted in another thread, just leave it in EV mode and let the engine kick in when needed

[coldstart]

As I've just posted in another thread, just leave it in EV mode and let the engine kick in when needed

@1speed: Kremmen probably means by "EV-mode" to just start the the car normally and thereby let the HV-battery recharge the 12V battery and let the ICE occasionally kick in to replenish the HV-battery.

[1speed]

I guess he's saying to use ev mode instead of accessory mode, which I will do from now on; but since I might have to replace the battery as it keeps misbehaving, I'm asking if it's possible\advisable to use a bigger one.

[coldstart]

... I'm asking if it's possible\advisable to use a bigger one.

You should probably discuss this with your Honda dealer of your choice.

As your car is still under warranty, any change to non-Honda parts would probably void your warranty!

Again: Why not just use it, as its designers intended it to be used and simply start it up normally?

I'm 66 years old and even I have a cell phone (capable of playing music by various sources).

My understanding (so far) was that humans are able to survive 3 weeks without food, 3 days without water, 3 minutes without air and 3 seconds without Google (slash Internet) - I will gladly add to this list 15 minutes of car audio 

[Lord Voltermore]

A few owners have had the battery replaced under warranty, but Honda would probably refuse if you have only done 3000km in 6 months +  . And I agree a non standard battery will probably void the warranty.
    Assuming it would even fit in the small battery tray.

I dont think a larger battery would necessarily solve your problem .All modern cars draw amps even when not in use  to power computers, alarm systems,  keyless locking signals etc. The amount may be small but its 24/7  and soon adds up, unless replaced with regular long journeys.  Even cars with full sized batteries can sometimes go flat in a couple of weeks.

If your battery has been allowed to get too flat it can affect its chemistry and  performance, which cannot be restored with normal charging.    But modern 'smart' chargers  often have a 'repair/restoration' mode that  pulse charges the battery in a special way.      If you can find a garage, or a friend ,who can do this for you once, the battery performance may improve.

Long term  stop using the radio in auxilliary mode, and occasionally give the car a long trip.    When I have sat in the car  whilst stationary  with the engine able to stop and start when it wants  the High voltage battery gives the 12v battery a  continuous 14v  charging voltage even when the engine is not running

You could also consider  connecting the car to a solar charger when not in use.  This might help keep the  battery topped up.      And/or  carry a small  power bank 'jump starter'  which  could start the car if the battery does go flat.  You can also use these for charging phones etc independently of the car.    Here are examples of both

[Kremmen]

I'm a very low mileage owner and my CTEK has kept my batteries in tip top condition on a few Hondas now

My old Civic 9G was nearly 10 years old when I p/x it and that was still on original battery, tyres and brake pads. All passed OK at each Honda service

[1speed]

Long story short, I've had the 12v battery replaced under warranty.

I bought the car used used 3 months ago with very low mileage, it's probably been sitting for 2 or 3 months prior to that, plus the radio listening must have accelerated an already dying battery.

I use the car everyday for commuting and every weekend for going out of town, I don't have charging issues.

The Jazz is not a cheap car for what it basically is, it should have had a bigger battery, not a smaller one than the previous model, which was already small.

Call me what you want, to me in 2024 sucks not be able to listen to the radio in your car for a few minutes without paying attention to technical details like which mode you're in, or having to constantly worry about the battery for ..... just not driving 2 days in a row?

When the warranty expires, if I still have the car, I'll replace the battery with a bigger one just like I did with no issues on my mk2 Jazz. 

I'll keep listening to the radio in EV mode and leave the smartphone to those who don't mind an ever shortening attention span and crappy sound quality 

[Lord Voltermore]

Most hybrids from other manufacturers also only have a  small 12v battery.   A few attempt to overcome the problem of the 12v battery going flat   by either using some cells in the High voltage battery as a back up,  or having an emergency start switch that enables you to start using some power from the HV battery.

Although these sound a good idea it can have disadvantages. Owners might put off replacing a 12v battery  when needed and rely instead on always being able to use the emergency back up from the HV battery.  And thus risk draining the HV battery to the point where it is permanently damaged, and very expensive to replace.

[Kremmen]

Our battery isn't put under any real strain as it doesn't have a starter motor to kick over

Therefore, a small battery is probably good enough and as I've found does need topping up if you're a low mileage driver

[Hicardo]

I regularly use the radio in accessory for mode for over 15 mins, and no issues.  My view would be your battery was already damaged, as you mentioned was a possibility.  And therefore there should be no need to change your habits with the new one fitted.  Unless you want to of course 

[Goodwin2110]

I'd obtain the simple battery tester and and have the battery checked for internal resistance and actual capacity first. In case you decide to replace: all my japanese cars were equipped with simple Furukawa batteries - they happened to last way longer than any aftermarket batteries..

[aphybrid]

A thought - is it possible to fit a 'bigger' battery, if not physically bigger is a same size bigger capacity available?

Sitting in car for 15 mins just listening to radio, better hobbies available unless1

[Tombola]

Most components on our cars get serviced, maintained or checked on a regular basis but the battery gets very little attention, probably because they have been tagged "maintenance free", I frequently use a smart charger to maintain a good level of voltage summer and (especially) winter, I have good access to a mains supply so it's convenient for me. I don't think fitting a larger capacity battery is the answer, look after the one Honda supplied by treating it to a top up charge with a Ctek or similar   

[Hicardo]

Never happened in our Crosstar, but 10 years ago, we had a Toyota Auris hybrid.  And we used to park up, chat, listen to radio all the time, mostly in ev mode, but often in accessory mode.  NEVER a problem in the 8 years or so we had the car.  However the Toyota dealer did tell me a couple times at service time that the voltage was a bit low on the 12v battery.  They recommended a long drive or two.  We already did fairly decent trips with it, so I was somewhat surprised.  Anyway, the battery never let us down, but I was aware that the dealer considered it problematical.  Odd that car was designed that way.  I suppose I tended to use EV mode (on the Toyota you could force it into EV mode) for these things, but the engine would always kick in eventually when it needed to. 

It probably should come with a recommendation in the vehicle manual of how to properly use the vehicle in these sitting around listening to the radio circumstances, but not actually driving.