Flat battery on 22 plate HRV?

[Jazzandjag]

My Advance Style now has a flat battery after standing for only 3 days (which it has done previously without a problem). Voltage was 3.75v so battery may not be ruined. Currently (!) on charge with my Ctec and I will contact the dealer later this morning. I will also buy a small booster pack which should deal with any recurrence when out and about.

[John Ratsey]

Did you report the problem to your dealer so it's added to the statistics and you can be on the list to get the software update once it is issued?

When I tried to use a smart charger on my flat battery it wouldn't do anything as the voltage was so low. I've bought one of the little booster batteries but won't know if it will work until I get another flat battery.

[Jazzandjag]

I will report this to the dealer, probably tomorrow now. After several hours Ctek charging most things seem back to normal. I have bought a Halfords jump starter, but the pre-sales info does state that it will not attempt to boost totally flat batteries below 3 volts.

Thinking about it, I only used the car on Friday, driving less than 10 miles. Apart from this journey, the car had stood for a week. Until Honda come up with a solution I will carefully monitor battery voltage!

[Peter55]

Hi all, not had this problem (yet), but I’m curious as to how a jump start works in our eHEV, and is the EV Battery flat as well.
When you connect the slave battery does the dash just spring into life or does the engine start as well.

If the EV Battery isn’t flat why doesn’t that put power into the flat battery or does the engine need to run as well

Sorry for the questions, but I very much doubt there’s any point asking Honda

[Steve_m]

The system needs 12volt battery power to turn on the power systems to connect the HV battery.
Using a small jump pack just give the 12volt battery enough power to turn on the power systems and then the HV battery can connect.

The HV battery wont be dead, Lion batteries have a very slow discharge rate.

If the HV battery is very low, it then takes a dealer to put the system into maintenance mode to allow the engine to start and charge the HV battery.

[John Ratsey]

The HV battery wont be dead, Lion batteries have a very slow discharge rate.

I would add that the HV battery is disconnected when the vehicle is switched off so the ongoing bug which can empty the 12V battery won't affect the HV battery. One job of the 12V battery is to reconnect the HV battery when the vehicle is switched on after which the 12V system is supplied from the HV battery.

The first indication of an empty 12V battery is that the remote key won't unlock the car. As this doesn't power on the vehicle (which, if I understand it correctly, can trigger the power drain fault) then this is one way to check if there's a battery problem in advance of needing to use the vehicle.

[Peter55]

The HV battery wont be dead, Lion batteries have a very slow discharge rate.

I would add that the HV battery is disconnected when the vehicle is switched off so the ongoing bug which can empty the 12V battery won't affect the HV battery. One job of the 12V battery is to reconnect the HV battery when the vehicle is switched on after which the 12V system is supplied from the HV battery.

The first indication of an empty 12V battery is that the remote key won't unlock the car. As this doesn't power on the vehicle (which, if I understand it correctly, can trigger the power drain fault) then this is one way to check if there's a battery problem in advance of needing to use the vehicle.

Presumably the Handbrake as well, but without power we wouldn’t be able to move to Neutral anyhow. So I’d better get myself a Booster

[John Ratsey]

Presumably the Handbrake as well, but without power we wouldn’t be able to move to Neutral anyhow. So I’d better get myself a Booster

I expect the vehicle needs to be switched on to release the electric handbrake plus getting the gear lever out of park and therefore special precautions are needed if recovering a dead vehicle.

I was led to understand that Honda hope to release the software update within a month but this schedule probably assumes successful testing.

[Hackney]

The handbrake will not release if the vehicle is in Hybrid mode, it will only release if it is in engine mode.I changed my handbrake to come on as soon as vehicle is shutdown.When vehicle is delivered handbrake has to be engaged manually.

[John Ratsey]

Whereas I have my handbrake set on manual as I don't want the pads sticking to the discs when the vehicle is parked at home.