2005 Cobalt LT

The Cooling Fan II relay makes noise, gets hot, and runs the fan at all times.

Relay is ok. The problem is not the relay itself.

Car will not crank with Fan II relay plugged in.

Car will crank, with Fan II relay pulled, but no fuel pressure.

No visible damage to wiring harness or connectors.

I think that the control for the relay is making contact with some other wire or ground. I removed the fuse box, there's a circuit board between the fuses on top and the wiring below. I can't see much of the circuit board, but it does not smell burnt.

There are no fault codes stored other than P2101, which I think is from me cranking it on it for long periods. There is nothing aftermarket on the car. Even the stereo is stock.

The wiring diagrams I have for the ECU pins does not match my car. Is there a difference in the wiring of 2005 and 2006 Cobalts?

What is the normal draw for a Cobalt with the key out and everything turned off?

Thanks!Any help will be greatly appreciated.

 

Current draw should be milliamps, for just the radio/clock. I'd look at the battery voltage to/from the fan relay contacts. Seems if it were drawing the voltage down due to short, it would blow the fuse. You also might unplug the fan, and try that, go from there.