My buddies car is starting to overheat while hes idling. I had him throw the air on to kick the second fan on, but it still didn't help. Where do you begin troubleshooting the fans if neither one will come on?

 

did you check the fuse and relays under the hood?

 

How do you know if the relays are bad?

 

You can just swap them one at a time with the fog light relay and see if they work in there.

 

With the car at full operating temperature of course? Its a 3 relay system, so each one will do a different thing? (seperate fan, different speed?)

 

Hes pretty sure that neither of the fans are working at all. I'm actually talking to him now and i'm gonna have him turn the car on and turn the air on, and swap out relays until the fan (fans) kick on. Because the car will definetly be calling for the fans with the air on.

 

Ok actually they do work if he puts the air on. But without the air on neither one goes on. And hes getting to about 210 and climbing. At what temperature should they or one of them be going on? Now if he unplugs that sensor on the water pump and they go on, that sensors bad right? Because thats the sensor for the pcm??

 

Stock fans don't come on until 226º, so there may be nothing to worry about.

 

Disconnect your MAF while the car is running and see if the fans kick on then , cause my car had the same problem untl I disconnected my Maf and then the fans came on at high speed

 

Yea, but then what? I can't keep it like that.

 

If he needs to drive, take out the fuse for the AIR pump. I've been driving my Formula since January like this. Runs fine. I hate to do it but I need a new PCM, (fans drivers are bad) and I simply won't have the money for at least another month.