George Allen

Hi All. This is my first post so please excuse me if i don't follow etiquette.

My 2002 Grand Cherokee will be working absolutely fine until..
All at once my temperature displays change from Centigrade to Fahrenheit, My windows won't open, heating stays on hot !
If i disconnect battery for a few mins then reconnect, everything will work fine but only for short time.
To add to this, i no longer have power to my stereo (measuring at the loom). I am not sure if this is related or not. I have checked all fuses and all are ok. This being said, i did find one thing strange and would love clarification if anyone can help please...

When checking fuses in the under dash box, i grounded one meter probe then probed each side of each fuse. I would expect around 12v to be present each side of each fuse. On a number of the fuses i was getting a voltage of about 4 volts ? As i was getting the same reading each side of the fuse, I at least new that the fuse was good. I expected one side of "all" the fuses to be connected to a common 12v supply, is this not the case ?

By the way, i have previously had damage to the door pillar cables, but this was repaired with ease and solved problem at time.

Fingers crossed one of you can help please.
Cheers.
George