PDA

View Full Version : Electrical Cooling fans triggered by otterstat but no diode in place



iflights
08-05-2025, 03:50 PM
Noticed that one of the two cooling fan diodes is missing in my car. The one for the Low pressure switch/Compressor (Pink wire) is present and tests ok. But the 2nd cooling fan diode (black orange wire) is missing and the male and female QDs are connected together where you would expect to see that diode.

Fans come on at the expected temperature when the otterstat closes. Adding a diode where it's expected prevents the fans from coming on.

Fans come on when AC is turn on.

Wiring matches what shows on the wiring diagram, and I don't see any PO hacks.

Any concerns for me to continue to run this way? I've had the car 10 years now and it's not been an issue, but now that I noticed I can't let it go.

Steve

Bitsyncmaster
08-05-2025, 06:50 PM
Looks like if your AC is on and the otterstat is on when you turn the key to first off position, it would back feed power into the one aux relay output. That would probably be a load to high. Now if you turn your key to off quickly, it probably would not matter. I think Bill was always saying to remove that diode which is probably why your PO removed it.

Bitsyncmaster
08-05-2025, 06:50 PM
Looks like if your AC is on and the otterstat is on when you turn the key off to first position, it would back feed power into the one aux relay output. That would probably be a load to high. Now if you turn your key to off quickly, it probably would not matter. I think Bill was always saying to remove that diode which is probably why your PO removed it.