Had some persistent error codes over the past week or so - P0562, P0151, P0152. Plus some spurious messages -'Traction Reduced' 'HDC Inactive' etc.

IID tool shows 14.7 volts with engine running but 11.5 volts with the ignition on (but car not started). In my mind this points to the alternator working OK, but the voltage is too low with just ignition on.

Could this be a correct assumption? Your opinions please. Thank you.

P.S. I put the battery on a charger for 6 hours the other day. Still got the issues described above.

Battery could be the cause. What is the voltage with the ignition off and the car ‘asleep’?

@ur20v - Fluctuates between 11.2/11.3/11.4 volts.

Similar issue I have with mine , run ok for approx 20 miles then all kinds of errors. Recharge overnight and same next time used. Eventually the battery light flashed and then stayed on pointing to the alternator being at fault.

If your battery is only showing ~11 volts after a being charged for 6 hrs you either have a big drain or the battery is possibly at fault.

What charger did you use - amps rating?

Charge it again with the earth lead removed for 24hrs if your charger is in 5-10 amps rated (12hrs for 20= amps and 72hrs for 1-3 amps) remove the charge afterwards, leave for an hour and let us know the standing voltage.

Do you have access to a battery tester, not a load tester but one that checks performance agains the battery rating (CCA etc) and gives the capacity?

How old is the battery and type? More than four years and I would suggest replacing it anyway.

Was the 14+v at tick over and what happens when you put load on it (heated screens, seats, HVAC on full, lights on) does it stay above 12.5v tick over and 13.7V over 2000 rpm?

You need a new battery

Battery.....I'm in the same boat as you the cold nights early at the start of the year killed it iv got a trickle charger on it for now just deciding which is the biggest battery I can fit to my 4.4 m62 engine

Thanks all. Time for a new battery methinks.