I have some questions about the cooling fan wiring for my 350 IROC. Right now, when I turn the key to the ON position, the primary fans will kick on and stay on forever. Once I start the car, the secondary fan will turn on and stay forever. This leaves both fans running constantly when driving the car.

I am 100% positive the previous owner made changes to force them both to run constant. As of now, it is keeping the car extremely cool and I would prefer to get both fans back working like stock.

After searching and reading the forums, I have beliefs which could use confirmation and couple questions.

Confirmations:
1) The primary fan is ECU controlled which uses the temp gauge on the front of the intake (This is also used to display the temp on the cluster)
2) The secondary fan is controlled by the A/C and/or the fan switch that is located in the passenger side head between cylinder 6 and 8.
3) The relays for both of the fans are located up on the driver side firewall next to the fuel pump relay.

Questions:
1) If both of the fan relays are located on the driver firewall, what is the single relay located between the battery (on the passenger front) and the radiator + fans?
2) How would someone (Previous Owner) "mod" the cooling fans so the primary kicks on in the run position and the secondary's once the car is running?
3) Is there a place where I can see/purchase/print out a full wiring harness diagram for my car? I am having a hard time following the broken out diagrams in the service manual (and getting them mixed together between the other engine options)

Thanks in advance for all the help!

 

I just noticed this morning my cooling fan was running on the drivers side but not the passenger side. Did the relay go bad or does it only come on when the car is in gear and running?

 

Haynes manual. just go to autozone, take off the shrinkwrap plastic of the haynes book, even pontiac firebird will work. flip to the diagrams.. If you need a picutre out of mine, i can arrange that to be uploaded. also, there a wire that goes to the a/c clutch. if the a/c system is on the fans will be on. to test a bad relay. turn on the a/c. of coarse there the fan switch, uses temp to turn on, it could be grounded out/bad, its on the block, its a sensor when heated grounds out and completes the circuit therefore triggering the relay.