[ThudnBlundr]

We had an interesting problem this morning. SWMBO took the ZOE out to go shopping, and after a couple of minutes she got an error along the lines of above. She also noticed that the battery wasn't fully charged despite having been plugged in overnight. She came back to swap to our PHEV and plugged it back in. The green light lit on the ChargeMaster point, but the car didn't charge.

I had a look around for anything obvious, but nothing came up. I check the 12V battery regularly, but I disconnected it and tested it again - health was 'good'. The thunderstorms forecast her came to nothing yesterday, so it's unlikely to be an electrical surge. I also did the old trick of turning the charge point off than back on again. Finally I took the ZOE for a drive to see if the error returned without luck, and after driving for 15 minutes, the range was 10 miles higher than when I set off.

I plugged it in when I got back, and everything seems to be normal ?? Any ideas what might have caused it? It's going for its 5th year service on Monday, so they might be able to have a look.

 

[cah197]

What home charger do you have?

 

[ThudnBlundr]

ChargeMaster (as I said ) - sorry, it's 7kW and supposedly 'smart' though all we've ever done is just plugged the car in. We've had it for 2½ years and only once had an issue a couple of months ago when it showed a red light and needed 'rebooting'

Some more info. The car was last charged 36 hours ago. According to the text messages, it went from 49% at 20:12 to 100% at 22:00 - 11kWh in 1¾ hours. So why was it at ~78% this morning? The car definitely wasn't 'on', as the car charged and the racket when you do get out if far too noticeable. What would drain over 2kWh from the drive battery in 36 hours?

 

[cah197]

I had this with my Rolec on the old Zoe. It would throw an error after the charge stopped, but clear itself.

Can you have a look at the RCBO and see if there’s any sign of burning?

 

[ThudnBlundr]

Thanks for that. Is the RCBO what I'd call a 'trip switch' in the CU? It's on a separate CU in the garage, along with the solar PV. Can I check it without removing it from the CU? Or do I need to isolate everything, disassemble the front of the CU and pull it out?

 

[cah197]

There should be one inside the charging unit itself, rather than the CU. But check both.

Someone else might be able to advise on common charge master issues.

 

[ThudnBlundr]

Thanks - I hadn't realised that there was one inside the charge point.

Will disconnecting the 12V clear any error codes in the system, or are they persistent? I must admit that I was quite surprised that the doors auto-locked while the 12V battery was disconnected, so there was some power in the system...

 

[andyfras]

There is no trip or RCBO inside the Chargemaster.

 

[cDy]

Will disconnecting the 12V clear any error codes in the system, or are they persistent? I must admit that I was quite surprised that the doors auto-locked while the 12V battery was disconnected, so there was some power in the system...

There will still be power if you just disconnect the 12V battery. The DCDC converter that keeps the 12V battery charged kicks in whenever anything happens. So if you've unlocked the car and opened the bonnet it will be active and charging (or just floating) the 12V battery. You need to leave the car for 10 minutes or so, after which the DCDC converter will switch off and THEN you can disconnect the 12V battery. See Battery tester for 12V battery for more details.

 

[ThudnBlundr]

Thanks @andyfras & @cDy.

They couldn't find anything obvious in the error codes at this morning's service, so I'll just have to keep a watch out to see if it happens again...