electronics intermittently die when service light come on

Hi guys,

Recently I went to town on my girlfriends Nubira. She had a problem where intermittently the Service light on the dash would go on and this would mean the following list of items wouldn’t work:

- power windows
- power mirrors
- thermo fans
- A/C fan

The car would still start and run and other things like the lights and radio still work (I think its everything that gets turned on when u turn the key to ‘ON’ stops working). Yet this was a pain as sometimes the windows would get stuck down etc. After a few days the problem would correct itself and everything would work again. Now she had taken it to mechanics before all said there was nothing wrong with the car and the problem would intermittently come back.

Recently the problem happened again and this time I noticed that when the car fixed itself the A/C fan in the card no longer worked at all and when you turn the fan speed there is no air flow and sure enough the service light comes on a second after and everything stops working again. I’ve traced the power window wires back around the car looking for a loose connection (I picked the windows as I thought they were the easiest thing to trace back), but found none. Basically I found that there is a proper connection from one side of the fuse to the battery and on the other side of the fuse there is a connection to the power windows (drivers side) when the car is working and no connection when the service light comes on. There is no power windows relay in the fuse box and so that rules that out but I’m almost out of ideas on what to do next. Any help would be greatly appreciated.

Thanks guys

Tony