so the cooling fan in my 85 iroc does not urn on all the time or for more than ten seconds the only way it will turn on is if i run the car till it hits 220degrees then shut it off and turn it back on. then it will spin for mabe ten seconds and shut back off the a/c wont turn it on eitherr please give advicee

 

 

Single or dual fan?

If you have a single fan, if you turn your AC on, the fan should turn on. If it does the same 10 second thing, then I'd go on the assumption that the fan motor is bad. Only because the fan turns on, would seem to be that the fan is getting power. Also, do you have a multimeter to check voltage? If you do, pull the plug on the fan motor and check for voltage 12v DC when the AC is turned on.

 

i would have to borrow one from a buddy but that no problem, just so im not mistaken i should start the car and just turn on the a/c then test the voltage doesnt need to warm up at all? thanks for the advice

 

Do you have ONE fan or TWO fans?

I re-read your posts.

Seems like you have one fan.

The fan operates from the Fan switch in the passenger side head. It also operates when the AC is turned on. Since you have "intermittant" power, I"m going to say the fan motor itself is bad. They run about $30 at Autozone. Remembe,r they're "reverse threaded" when you take the nut off.


When the fan switch in the Passenger Head hits it's temp, it grounds to the block sending a signal through the relay to the fan to turn in. The relay is located in the drivers side firewall, probably facing the front of the car. It will have four wires coming off to it. One is a relatively fat red wire.

The relay then energizes turning the fan on.

The AC circuit bypasses the switch in the motor and just tells the relay to turn the fan on.

As you have power occasionally, the fan "tries" to turn on...leads me to believe that your fan motor is bad. But, the only way to check for sure is to check for voltage when the fan is "supposed" to be on. Either engaging the AC or letting the car warm up.

 

well the fan has never even tried to turn on with the a/c only when it gets hot and I restart it

 

The only way to know for sure is to troubleshoot. Or, start throwing parts at it which can get expensive. But...I'd pull a fan and ground it to the battery first. Remove a fan, rig up two wires, one to each terminal on the fan and one to each terminal on the battery. IF the fan spins and stays spinning, the motor is good. It may spark a bit and you have to have someone else hold it...but be careful because it kind ot starts suddenly. Alternately, you can just run two longer wires down from the battery terminals to the fan terminals while it's still mounted but you'll have to get under the car to do this. This bypasses everything except the fan. So you'll know if the fan motor is good by doing this.

IF the fan motor is good, start with jumpering the two fat wires on the fan relay with the rlay out of the car and the fan hooked up normally. This bypasses the relay and should start the fan. Do this for each relay. if the fan spins, the relay is bad. If it doesn't spin, it's more than likely not the relay. Also, make sure all the connectors IN the relay connector are fully seated. When I repalced my relay I pushed all the pins back when isntalling the new switch. So I had to have a friend really hold the wires in place while I put the relay in.

YOu then have the inline fuse just before the relay (You'll have to dig in the harness to find it) or you can try by replacing the switch. Alternately, with the on (Shouldn't need to be running, just ignition in the 'on' position, remove the fan switch connector and ground the wire (not the connector, just the wire going to it). This will simulate the ground signal the switch gives when it activates. IF the fan spins when you do this, the switch is bad.

Other than a bad ECM, this should cover all the troubleshooting that can be done for the fan system. if it STILL doesn't work after all this. Brother, you got issues.

 

thanks man ill start troubleshootin this weekend but i did notice the relay near the left headlight (if ur looking at the car from the front) has silicone on it so it may have been checked before but idk

 

I don't know what relay that might be...the fan relays are both on the drivers side up near the firewall. Good luck on your troubleshooting!

 

thanks guy! but i did notice the wires that come out of the fan motor lead up to it right behind the passenger headlight.. mabe it could be different between our cars?

 

It could be a difference in wire routing between the Firebirds and Camaro's. The two relays are only found on the drivers side firewall so the wiring must go there eventually