A week to get a 12V battery? Honda eNy1
Discussion
I've had my eNy1 for 26 months, and really like it, although it was a cheap PCP deal so it'll be going back in April 2027.
It's had 2 services, 2 recalls for software updates, I average about 3.6 miles / kWh and had been faultless until Bank Holiday Monday.
I hadn't used it for about 3 days, but the car hadn't charged overnight as scheduled, and wouldn't turn on, at all. I suspected the 12V battery immediately, the EV forums will tell you how they fit weedy ones. I had to look in the printed owners manual (there is one!) to find it. It's under a cover with only 2 clips under the bonnet, nut there is no indication of where it is. The following shows the reading 
The owner's manual has instructions on jumping it too, although I've done it many a time in the past on ICE cars. I don't have proper jump leads, but to get enough power to 'power up,' I used an old 12V battery (reading 12.2V), and instrument leads, old ones are handy sometimes!
As soon as power up is achieved, the main traction battery charges the 12V battery:
I contacted a Honda dealer, and he said I had to have a battery test before he could fit one under warranty (if the battery had a shorter one than the car, I'd have changed it myself). Many would have just called Honda Assist but I expect they would have jump started it too. I did this. To be fair, they checked it at 3pm the same day, removing it to do a load test. It came up 'fail' they said, but not in stock so ordered, fair enough.
I'd heard nothing after 3 days and called them. They DID call back, it apparently has to come from Belgium! So, 7 days plus to change a 12V battery? It's also a 23 mile round trip each time. Not the dealer's fault, and I know they've stopped selling them new in the UK now, but this seems a bit daft.
The car has actually been OK the last few days, charging overnight too, but a new battery is needed. I wonder now if something drained it. Not an internal lamp, they're LEDs, perhaps the boot latch motor, it did stick once.
It's had 2 services, 2 recalls for software updates, I average about 3.6 miles / kWh and had been faultless until Bank Holiday Monday.
I hadn't used it for about 3 days, but the car hadn't charged overnight as scheduled, and wouldn't turn on, at all. I suspected the 12V battery immediately, the EV forums will tell you how they fit weedy ones. I had to look in the printed owners manual (there is one!) to find it. It's under a cover with only 2 clips under the bonnet, nut there is no indication of where it is. The following shows the reading The owner's manual has instructions on jumping it too, although I've done it many a time in the past on ICE cars. I don't have proper jump leads, but to get enough power to 'power up,' I used an old 12V battery (reading 12.2V), and instrument leads, old ones are handy sometimes!
As soon as power up is achieved, the main traction battery charges the 12V battery:
I contacted a Honda dealer, and he said I had to have a battery test before he could fit one under warranty (if the battery had a shorter one than the car, I'd have changed it myself). Many would have just called Honda Assist but I expect they would have jump started it too. I did this. To be fair, they checked it at 3pm the same day, removing it to do a load test. It came up 'fail' they said, but not in stock so ordered, fair enough.
I'd heard nothing after 3 days and called them. They DID call back, it apparently has to come from Belgium! So, 7 days plus to change a 12V battery? It's also a 23 mile round trip each time. Not the dealer's fault, and I know they've stopped selling them new in the UK now, but this seems a bit daft.
The car has actually been OK the last few days, charging overnight too, but a new battery is needed. I wonder now if something drained it. Not an internal lamp, they're LEDs, perhaps the boot latch motor, it did stick once.
I know absolutely nothing about your car but is that the "big" battery trying to charge the 12v one? Whatever it is it's either the system trying to charge a knackered battery or a faulty charging system that's knackered the battery.
By all means chuck a new 12v battery in there but you'll need to keep an eye on what's going on with voltage.
By all means chuck a new 12v battery in there but you'll need to keep an eye on what's going on with voltage.
Yes, but I will be checking that. The charging voltage was so high because it was so drained, I've seen voltages that high before on other cars. Anything below 11V, a battery is considered unrecoverable, usually.
There haven't been any warning lamps regarding the charging system, which the car has systems to detect. Everything is under warranty anyway, servicing was free in the deal so they've been done at the same Honda dealer. Car has done only 12,800 miles.
There haven't been any warning lamps regarding the charging system, which the car has systems to detect. Everything is under warranty anyway, servicing was free in the deal so they've been done at the same Honda dealer. Car has done only 12,800 miles.
It's bizarre really.
If they haven't mastered the care and feeding of good old lead acid batteries, how can they be trusted with anything modern?
You could understand the odd edge case, where someone leaves a car idle for months or does something silly, but in normal use, starter batteries on IC cars frequently last 8+ years these days, despite getting a hard life with Stop/Start.
I wouldn't be surprised to find Tayna had the battery in stock...
If they haven't mastered the care and feeding of good old lead acid batteries, how can they be trusted with anything modern?
You could understand the odd edge case, where someone leaves a car idle for months or does something silly, but in normal use, starter batteries on IC cars frequently last 8+ years these days, despite getting a hard life with Stop/Start.
I wouldn't be surprised to find Tayna had the battery in stock...
You can connect to the car by Wifi using the app to change charging schedule, turn on air-con, check battery status, start and stop charging if plugged in, unlock the boot to give remote access, etc. So the 12V battery must work quite hard if you interrogate it a lot, hence my surprise / disappointment to see that it is only 45 Ah. 
Quite common for the feeble 12v batteries to cause problems on Ev..
Friends Toyota one dies, as he leaves it for weeks. He bought battery booster jump starter (Halfords Advanced) which kicks it into life.
I bought same for my Skoda. Not needed it.. yet. I keep in glovebox as you can unlock it with physical key if it dies & keyfob opening doesn’t work. Don’t fancy climbing through to the boot if stored there!. Can easily get to the 12v battery terminals in mine to do this.
Daughters partners Leaf 12v killed it after being left for a week in winter. He used my booster to get it going. Good test!
Friends Toyota one dies, as he leaves it for weeks. He bought battery booster jump starter (Halfords Advanced) which kicks it into life.
I bought same for my Skoda. Not needed it.. yet. I keep in glovebox as you can unlock it with physical key if it dies & keyfob opening doesn’t work. Don’t fancy climbing through to the boot if stored there!. Can easily get to the 12v battery terminals in mine to do this.
Daughters partners Leaf 12v killed it after being left for a week in winter. He used my booster to get it going. Good test!
45Ah isn't that feeble - most small petrol cars will have that size, or even smaller. The battery isn't doing much compared to an ice vehicle.
Generally EVs check the 12V battery every few hours and charge it if needed but some (maybe all?) EVs won't charge the 12V battery if the traction battery is low - and low can be like 30%, so easy to get caught out.
Generally EVs check the 12V battery every few hours and charge it if needed but some (maybe all?) EVs won't charge the 12V battery if the traction battery is low - and low can be like 30%, so easy to get caught out.
Update:
I'd heard nothing for a while, considering they expected the battery to be here by Tuesday 2nd June so I contacted them again. It's still on
back order from Belgium. That's 13 days from the 12V battery being diagnosed as kippered, still no replacement in the country.
What if it was completely kaput? I suppose I could dump the car at the dealer and stamp my feet for a courtesy car, but powering it up for 10 mins every day, even if I don't drive it, is keeping it charged enough, at the moment.
I'd heard nothing for a while, considering they expected the battery to be here by Tuesday 2nd June so I contacted them again. It's still on
back order from Belgium. That's 13 days from the 12V battery being diagnosed as kippered, still no replacement in the country.
What if it was completely kaput? I suppose I could dump the car at the dealer and stamp my feet for a courtesy car, but powering it up for 10 mins every day, even if I don't drive it, is keeping it charged enough, at the moment.
Eh? It's free under warranty. It's been fine the last 2 weeks, with the said boost, It was at 12.05V after just 36 hrs the last time I checked it.
I've chased it up twice and am just going to wait now. The longer, the possibility of a 'perk' perhaps? But it's free servicing under the PCP deal anyway.
I've chased it up twice and am just going to wait now. The longer, the possibility of a 'perk' perhaps? But it's free servicing under the PCP deal anyway.
Still waiting. I was waiting for a change to update.
It'll be 5 weeks on Tuesday and I'm going to suggest they come up with a solution. Either get permission from Honda UK to acquire one locally (there must be an equivalent), take one out of a forecourt car maybe (unlikely) or wait for me to return the car to them on a breakdown truck.
I'm not due to leave it unattended for a long period until 2nd October (a week abroad) so it MUST be sorted by then, shirley?
When the car is turned on, or charging at home, the 12V battery gets charged (I checked), so as long as I charge it, or power it up for 10 mins every day, it's OK.
It'll be 5 weeks on Tuesday and I'm going to suggest they come up with a solution. Either get permission from Honda UK to acquire one locally (there must be an equivalent), take one out of a forecourt car maybe (unlikely) or wait for me to return the car to them on a breakdown truck.
I'm not due to leave it unattended for a long period until 2nd October (a week abroad) so it MUST be sorted by then, shirley?
When the car is turned on, or charging at home, the 12V battery gets charged (I checked), so as long as I charge it, or power it up for 10 mins every day, it's OK.
Mark V GTD said:
So how did this pan out? Mine has just died after leaving it three weeks at an airport car park. AA on the way.
What was the charge in the traction battery when you left it?I haven’t seen anything definitive on how eNy1 looks after its 12V battery but some sources suggest it doesn’t get checked at all by the car when parked, which surely can’t be correct?
i am tempted to do this but wonder if it would invalidate the warranty if anything else goes, especially as it IS part of the electrical system, and not as irrelevant as non-OE brake pads, tyres or dampers etc.
Since it's a common issue, I wonder Honda dealers have loads of them waiting for new batteries.
My first warning was when the car failed to charge overnight (the app showed me this, which undoubtedly used some of the remaining 12V battery power), and when I unlocked it, the mirrors didn't automatically fold out. I hadn't powered it up or used it for 3 days. I've since discovered the emergency key in the fob if needed!
Since it's a common issue, I wonder Honda dealers have loads of them waiting for new batteries.
My first warning was when the car failed to charge overnight (the app showed me this, which undoubtedly used some of the remaining 12V battery power), and when I unlocked it, the mirrors didn't automatically fold out. I hadn't powered it up or used it for 3 days. I've since discovered the emergency key in the fob if needed!
The root of the problem won't be the battery.
Either it's not being charged properly, or it's being drained excessively while it's not being charged.
Unless there is something you can do to reduce the drain while the car is not being driven, the problem will most likely need some kind of software or firmware fix to change the charging regime or reduce current drawn when idle.
It's like the BMW bike I had, however new the battery, the excessive permanent draw from the ECU would flatten it in a couple of weeks of not being used.
The only solutions were to disconnect the battery when not using the bike or add some sort of trickle charger. These days most vehicles seem to go into progressively deeper sleep modes to reduce drain when idle for more than a day or three.
Either it's not being charged properly, or it's being drained excessively while it's not being charged.
Unless there is something you can do to reduce the drain while the car is not being driven, the problem will most likely need some kind of software or firmware fix to change the charging regime or reduce current drawn when idle.
It's like the BMW bike I had, however new the battery, the excessive permanent draw from the ECU would flatten it in a couple of weeks of not being used.
The only solutions were to disconnect the battery when not using the bike or add some sort of trickle charger. These days most vehicles seem to go into progressively deeper sleep modes to reduce drain when idle for more than a day or three.
It might be illuminating to know what the charging regime is on eNy1.
Our EV is a Kona and on the Gen1 cars it was recommended on forums to carry a booster charger.
Ours is a Gen2 and, touch wood has been fine so far (18mths) including during airport parking for a week, but on its first service there was a software update to the 12V charging circuit - so even after all this time they hadn’t cracked it.
I think the manufacturers do try and minimize the 12 V charging in order to preserve the traction battery range. If the traction battery drops below 30% (typically) they stop charging.
Our EV is a Kona and on the Gen1 cars it was recommended on forums to carry a booster charger.
Ours is a Gen2 and, touch wood has been fine so far (18mths) including during airport parking for a week, but on its first service there was a software update to the 12V charging circuit - so even after all this time they hadn’t cracked it.
I think the manufacturers do try and minimize the 12 V charging in order to preserve the traction battery range. If the traction battery drops below 30% (typically) they stop charging.
Sheepshanks said:
....
I think the manufacturers do try and minimize the 12 V charging in order to preserve the traction battery range. If the traction battery drops below 30% (typically) they stop charging.
A lead acid battery should spend its life more than half charged.I think the manufacturers do try and minimize the 12 V charging in order to preserve the traction battery range. If the traction battery drops below 30% (typically) they stop charging.
So to fully charge the OP's 12V battery is about 1/4 of a kWh.
Seems misguided to not look after the 12V battery, if it results in the car having zero range.
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