Versailles wrote: ↑Fri Sep 20, 2024 6:34 amDytham,
I've only read back through the last ½ dozen or so posts.
But, the "Auxiliary" battery you have in the rear of the car is probably the same as the auxiliary battery under the armrest in the C5X PHEV.
There are a large number of owners of the C5X that have reported similar issues "can will not run in electric only mode" It turns out the this battery controls the Hybrid systems. Even though the C5X is only max 2 years old there have already been a number of cars where this battery had failed and replaced under warranty.
12.5 volts on a 12 volt battery at 'rest', means nothing, what's it doing under load? Get you dealer to test that battery on their diagnostic equipment.
I did not use my car in Ice mode in August, and I coveed over 200 miles in EV only mode, and never needed to recharge the 12 volt battery under the bonnet.
I think, your problem is 12 volt battery related and very probably the one in the back.
Yes Versailles. The eventual resolution to my problem was the dealer replaced the auxiliary battery in the boot and it will now run in Electric mode again.
So that battery had failed in 10 months from new - does not provide any confidence that another new one will be needed next year.
Indeed, and be warned that the cost of these when you next have to replace it (when out of warranty - and these likely wont be covered under any extended warranty as they are classed as service items) is anywhere from £1,600 to £7,700 depending on type and version and classification rating with the exchange version of the basic traction battery being £4,423
That's the cost - thought you'd want to be prepared....
For the exact one, I'd need your VIN, but as I said it depends on which battery this is. But if it's just the VLV network separation device, then a more reasonable £382 - £735 - again depending on model and device.
Pop a picture up of the one concerned so I can match it up.
Juan Sheet wrote: ↑Wed Oct 02, 2024 9:24 am
That's the cost - thought you'd want to be prepared....
For the exact one, I'd need your VIN, but as I said it depends on which battery this is. But if it's just the VLV network separation device, then a more reasonable £382 - £735 - again depending on model and device.
Pop a picture up of the one concerned so I can match it up.
dytham wrote: ↑Wed Oct 02, 2024 7:25 am
I find £1,600 to £7,700 hard to believe.
Apparently, the early C5X's suffered similar issues, as they had CHEAP CHINESE batteries when built, these were getting replaced regularly, so they decided to fit a better quality battery in production - saved them money in the long run. Doesn't pay to cut corners.
I had the same problem December 23 and they replaced the battery although not under warranty. Having the same problem again approximately 11 months later.
I was wondering how this battery is charged. I do most of my mileage on electric mode so the engine doesn’t run and drive the alternator. Under these conditions how dose the batín the engine bay get its charge.
Can I use a 12 volt battery charger to charge the aux battery or is this a lithium battery.
