Dead Honda e

[Gerynant24]

Well, this is what Honda are telling us. Would be good to see an actual mechanism to know if this is the case or not. Will be trying the key when we get it back to see if this is the case.

[digib]

Hello,

New person here, just signed up to report this issue on our 21 plate e today.

Wife drove it this morning for the school run all normal, its been sat on the drive all day. About 5pm the alarm starts going off and none of the key fobs will shut it off. Alarm stops after a while and everything is completely dead. Used the manual key to get in the drivers door (a bit fiddly but worked fine) and popped the bonnet to test the 12v battery, nothing. So got it on trickle charger to see if we can get any life into it for the morning, if not it will be a trip to Halfords for a new battery!

The car is charged to 95% just seems odd that this can't support the 12v system at all in the situation. I'm guessing "giving it a run up the road" like an ICE car doesn't work in the same way if I could get enough power in it to drive it...? How does the alternator/BMS work for 12v in these EV's?

[londiniumperson]

Hello,

New person here, just signed up to report this issue on our 21 plate e today.

Wife drove it this morning for the school run all normal, its been sat on the drive all day. About 5pm the alarm starts going off and none of the key fobs will shut it off. Alarm stops after a while and everything is completely dead. Used the manual key to get in the drivers door (a bit fiddly but worked fine) and popped the bonnet to test the 12v battery, nothing. So got it on trickle charger to see if we can get any life into it for the morning, if not it will be a trip to Halfords for a new battery!

The car is charged to 95% just seems odd that this can't support the 12v system at all in the situation. I'm guessing "giving it a run up the road" like an ICE car doesn't work in the same way if I could get enough power in it to drive it...? How does the alternator/BMS work for 12v in these EV's?

You just need to make sure the car is 'On', then it will charge the 12v battery. If is was totally flat, then I would say 20-30 should be enough for at least the next 24hrs.

[EEEE]

Hello,

New person here, just signed up to report this issue on our 21 plate e today.

Wife drove it this morning for the school run all normal, its been sat on the drive all day. About 5pm the alarm starts going off and none of the key fobs will shut it off. Alarm stops after a while and everything is completely dead. Used the manual key to get in the drivers door (a bit fiddly but worked fine) and popped the bonnet to test the 12v battery, nothing. So got it on trickle charger to see if we can get any life into it for the morning, if not it will be a trip to Halfords for a new battery!

The car is charged to 95% just seems odd that this can't support the 12v system at all in the situation. I'm guessing "giving it a run up the road" like an ICE car doesn't work in the same way if I could get enough power in it to drive it...? How does the alternator/BMS work for 12v in these EV's?

You just need to make sure the car is 'On', then it will charge the 12v battery. If is was totally flat, then I would say 20-30 should be enough for at least the next 24hrs.

My BM2 seems to suggest otherwise. The battery seems to be 'managed'. Since it is dark I haven't looked too much since installing the BM2 , but I have a feeling that with the car fully on and in park, the 12v is not charging or even maintained.

I noticed this on my commute where I pulled over for a few minutes and put the vehicle in park (to avoid brake hold keeping the brake lights on), and the BM2 reports a dip back to natural resting 12v instead of the 14v+ for charging. I won't say it has a mind of its own, but I think there are issues with it for sure. It wasn't even holding it at the 12.6v that it normally does when it is not charging (but the vehicle is otherwise in motion).

Now that I have the BM2, I will try and work out when the 12v batt is being charged or not. Once I have enough observations I think I will put up another post (observations so far include, if the HV is charging, the 12v will be held at 13.3v which is odd. If the HV finishes charging, the 12v doesn't seem to be held at 13.3 when plugged into mains. Something is sucking a bit of power every 2 hours. The 12v charging overnight seemed to stop bang on midnight for no reason also). The car took a reasonable dip at 5:30pm despite not being used for the entire day. 5:30 pm my wife would have walked past it with other Honda keys and devices).

If Honda read this - I would happily accept losing 1% of the main EV battery to keep the 12v battery at it's maximum all the time, so that it will always start and never leave me broken down looking stupid and regretting my purchase and tarnishing the previously excellent reputation of the brand.

Drove the prelude to work today despite the torrential rain.

It's all very annoying...

[AdamM94]

Also walked up to a dead Honda yesterday

Trek to get a Halfords trickle charger showed 3.4v when first connected and would refuse to charge as it didn't recognise the voltage as being a car battery... Booster battery managed to get it back up and running and now that the battery is reporting just under 12v the trickle charger is happy to top it up. Hoping the low voltage hasn't completely destroyed the battery

Do Honda cover battery issues under warranty? Car hits 3 years on November 24th and is already booked in for an MOT on Tuesday where I might just bite the bullet and buy a new battery.

[EEEE]

If the 12v has gone down to 3, it's definitely damaged and will never charge up to full capacity again. You can pick up a cheapy battery from eurocarparts for a little over 50. The yuasa from Halfords is closer to 90.

Tomorrow I'll see if I can fit the larger battery as it's barely any extra cost but much more capacity.

[ZeroEmissionRequiem]

This just happened to my car (first reg 2022-06, done a little over 9000 km total). I parked it the day before yesterday and plugged it in, didn't go anywhere yesterday, and today it was completely dead. Charging light wasn't blinking, either. Since the charger couldn't be released, I had to pull the release cord under the glovebox to get it off before opening the bonnet. I called Honda's road service, and they sent a guy who used a battery booster to wake the car up. His device said the 12V battery was at 3.00 volts, so it'll probably need to be replaced. After this, I let the car "run" for about 20-30 minutes before driving, and afterwards it performed normally for multiple short drives.

Once I got home, I connected my (new...) Defa 12V charger to the battery in an attempt to restore it overnight. It was showing 1/5 bars when it started, curious to see what it's telling me in the morning. Probably best to use the charger at least once a month in the future. I also bought a Telwin portable starter, in case this ever happens again.

It's on life support now:

[EEEE]

I would avoid using a 12v charger at the same time as charging the HV battery. My observations with the bm2 is that when the HV battery is charging, the 12v receives a dumb charge of 13.3v continuously whilst the HV is charging. This will confuse the external 12v charger and potentially lead to trouble.

Small update on my side. I managed to fit the much larger 005 battery which is basically a 6inch deep version of the 053, this jumps the storage capacity up from 45ah to 65ah. I had to remove the battery tray (lift out, no fasteners), and use a piece of metal to replace the battery tie down bracket which is specifically molded for the 4.5inch 053 battery and thus unusable for the bigger battery.

So far so good, it fits, it clamps down, and the bm2 seems to suggest it holds a much higher voltage than the OE battery which must have been passed its best. In Panasonic s lineup, it was there most basic battery.

Drove around for an hour, and the bm2 showed 3x 14v+ charging sessions. Will wait to see what it settles down to. The negative battery terminal does incorporate a current sensor (aka ELD sensor) which must play a part in the charging determination. I will plug in my scan tool and see what secrets it might give up.

[peniole]

Hello,

New person here, just signed up to report this issue on our 21 plate e today.

Wife drove it this morning for the school run all normal, its been sat on the drive all day. About 5pm the alarm starts going off and none of the key fobs will shut it off. Alarm stops after a while and everything is completely dead. Used the manual key to get in the drivers door (a bit fiddly but worked fine) and popped the bonnet to test the 12v battery, nothing. So got it on trickle charger to see if we can get any life into it for the morning, if not it will be a trip to Halfords for a new battery!

The car is charged to 95% just seems odd that this can't support the 12v system at all in the situation. I'm guessing "giving it a run up the road" like an ICE car doesn't work in the same way if I could get enough power in it to drive it...? How does the alternator/BMS work for 12v in these EV's?

You just need to make sure the car is 'On', then it will charge the 12v battery. If is was totally flat, then I would say 20-30 should be enough for at least the next 24hrs.

My BM2 seems to suggest otherwise. The battery seems to be 'managed'. Since it is dark I haven't looked too much since installing the BM2 , but I have a feeling that with the car fully on and in park, the 12v is not charging or even maintained.

I noticed this on my commute where I pulled over for a few minutes and put the vehicle in park (to avoid brake hold keeping the brake lights on), and the BM2 reports a dip back to natural resting 12v instead of the 14v+ for charging. I won't say it has a mind of its own, but I think there are issues with it for sure. It wasn't even holding it at the 12.6v that it normally does when it is not charging (but the vehicle is otherwise in motion).

Now that I have the BM2, I will try and work out when the 12v batt is being charged or not. Once I have enough observations I think I will put up another post (observations so far include, if the HV is charging, the 12v will be held at 13.3v which is odd. If the HV finishes charging, the 12v doesn't seem to be held at 13.3 when plugged into mains. Something is sucking a bit of power every 2 hours. The 12v charging overnight seemed to stop bang on midnight for no reason also). The car took a reasonable dip at 5:30pm despite not being used for the entire day. 5:30 pm my wife would have walked past it with other Honda keys and devices).

If Honda read this - I would happily accept losing 1% of the main EV battery to keep the 12v battery at it's maximum all the time, so that it will always start and never leave me broken down looking stupid and regretting my purchase and tarnishing the previously excellent reputation of the brand.

Drove the prelude to work today despite the torrential rain.

It's all very annoying...

Already done on another post here viewtopic.php?p=7503#p7503

[EEEE]

Thanks for that, I hadn't observed as many scenarios, but that seems to ring true with my observations of having the bm2 for less than a week.

The 13.3v charging is dumb. 13.3v isn't enough to really charge it properly, and the HV charging normally completes relatively quickly on a 7kw wallbox. No wonder the 12v batteries are continually dying, they are not being charged properly to keep them alive and serviceable. Without a CCCV staged charging, the battery will not be looked after properly.

Its also further stupid that if you plug in to charge the HV, and it only charges 10 or 20% , that's not enough time either for the 12v to be really looked after.

regarding observation #7 , I'm not sure this is strictly accurate. I don't think the HV soc% comes into it. I just reviewed my data from yesterdays test drive, and I drove off at 16:42 with 100% SOC in the HV, and I can see from the bm2 that 14.4v charging started immediately. It then pulses in and out over my 1 hour journey , dropping to 12.6v each time (which I believe is the maintained voltage by the inverter).

Now that the new battery is in. I will drive it for a week and monitor.