i was 200KM into my 600KM trip when the gong sounded and a messege on the dash said "-24ºC". and for about 30 minutes the temp reading on the OBC was jumping around from 0ºC to -82ºC. I was watching the thing change temp every second, in huge amounts, one second it was on 0ºC then it would go to -40ºC, and then after 30 minutes the temp. slowly rose to 17ºC again and hasn't gone nuts since. I was wondering what would cause this, i'm hoping it won't do it again on the way back home. It didn't cause any problems with the car, it was just worrying me at first what was wrong.