Mrs Si spotted a message displayed beside the courtesy light a few days ago, saying "passenger airbag off" when the switch was in the on position, and I noticed the stop/start wasn't working. As I rarely drive the F2, and Mrs Si only does short journeys (5-6 miles), I thought I'd check the battery voltage. I had 12.4 volts 1 hour after stopping driving, and 14.2 volts with the engine running. Thinking the battery needed a decent charge, I plugged my intelligent charger in, which switched off after less than a hour. Rechecking the voltage, it only showed 12.5v.

This led me to suspect one of the following,

1) The battery is goosed.
2) The charger is goosed.
3) They're both goosed.....

Has anyone else experienced this? I know a low battery voltage will disable the stop / start, but not the actual value, or if a low voltage would disable the passenger airbag. Any info on this would be much appreciated.

Doesn't the Passenger Airbag light come on (briefly) every time you start the car? I think it does on mine..

And battery voltage definitely affects the stop / start amongst a host of other mysterious other things. Cabin temp, outside temp, Man U winning a game, etc..

Yes, the air bag light comes on as a bulb check.