Cooling fans not working on my Grand Prix GT. replaced all 3 relays & eng coolant temp sensor & added a new thermostat . Any ideas ????

check all fuses seen this where a fuse marked fore something else actually had power to the secondary panel test every one ok even if you think you already did

I think there are two temperature sensors, one that reads out in the instrument cluster and a seperate one that controls the radiator fan (s). When you turn on the AC the radiator fan (s) should come on. If not you may have a bad fan motor or the secondary temp sensor I mentioned. Try taking 12 volts from the battery straight to the fan motor, if it doesn't run....the motor is bad. Good luck with it.

Already checked both fan motors to direct power and they are fine. Have replaced eng coolant sensor & dash meter is working... Have in clipped wiring to temp sensor & made a open loop to engage fans at high, fans will not run with A/C on as well... Power running to wiring harnesses so lost as to what to check next???

If both temp sensors are known to be good and all of the relays are known to be good you might try jumpering the relay contact sockets (bad connection). If none of these things bring the fan(s) on you may very well have a computer problem. The signal from the fan temp sensor tells the computer to energize the fan relay so once again if the fan temp sensor is good the relays, connections, and motors are good it only leaves the computer. Good luck with it.

how hot did it go up to? 220?

In most cases the power is applied to motors, lights , etc. the control relay is making and breaking the ground. Just thought I'd bring this up to you as you said the harness had power on it, that would be a normal situation any time the battery is connected. Good luck with it.

Idk

I ran into a similar situation on a 2000 Grand Prix GT and I know this post is very old but it took me some time to track it down so it might help someone in a similar situation to save some time. What I ended up finding out was that one of the small ground wires on the bell housing behind the main battery ground had broken from the eyelet. Everything come out good on the scanner with no codes set. The air conditioning quit working, along with the coolant fans, and it didn’t want to let you shift it out of park when applying the brake. Put a new eyelet on and voila problem solved. Hope this helps someone else to save some time.

Body control module

I have a 01 Pontiac Grand pre Gt and my coolant fans just stoped working .how do I fix the issue

@ gurufmfy8 the fans don't run through the bcm they run through the ecu.