My cooling fan doesn't turn on at all, the car overheats in standstills. How do I track the problem down to my switch or the fan motor? Any tricks? TIA

 

ttt

 

Disconnect the fan and remove it. Connect a couple pieces of wiring to the fan motor and connect touch one the positive batery terminal and one to the ground. That way you can test the motor.

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1991 Camaro Z-28 305ci 230hp
1985 Camaro Coupe 331ci 300hp
http://www.geocities.com/speedstar38...Speedstar.html

 

yea just splice open a fan wire and run a wire from that to the positive battery terminal.. the fan should go on..

 

ok, well the fan works, so it must be the switch right? Before I buy a new one and crawl under the beast, any other probs it could be? Thanks guys!

 

yea it could be the fuse, or the fusible link.. check both before buying anything.

 

it could also be the fan relay or the coolant temp. sensor. does the fan come on when u turn on the A/C? if it does, the relay is still good. the coolant sensor is located next to the 'stat housing on the 305 TBI. also, check the fan fuse. later

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"WARNING: Objects in mirror are about to disappear VERY quickly!"

 

Before you remove the switch, check it. You can do this by pulling the plug off it and grounding the plug to the block with a short piece of wire. That's all the switch is, a ground that connects the wire to the block at the correct temperature so the relay will close and send 12 volts to the fan motor. If the fan comes on when the switch wire is grounded (and the key is in the run position) then the switch may be bad. When you ground it (with the engine off) you should be able to hear the relay click as it closes. I can hear it on my 86 IROC. The relay for it is located beside the radiator next to the battery.

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Z's r Best

 

well I checked the switch and it seems to be fine. The fan doesn't go on at all when I turn on the A/C. So that means the relay is bad right? I understand its located around the battery? I also replaced the coolant temp sensor, it was only three bucks. I cannot find a fan fuse anywhere, and all the fuses under the dash are ok. Help? Thanks again guys!!

 

just checked the battery area and I found a plug with a 20amp fuse in it to the left of the battery on the inside of the fender wall, it was ok. It had a thick red wire and a thick orange wire coming out of it. was that the relay or inline fuse?? I also notciced a black plastic power distribution cradle to the right of the battery that had several wires bolted down together, they all appeared to be connected ok. I guess I didn't find the relay.

 

The relay on my IROC is just a small 1.5" X 1.5" black box with 4 wires running to it. Not sure where yours might be. A relay for mine is only $10. You need to find the relay to check it. The fuse under the dash only supplies power to operate the relay on mine. The power that actually runs the fan comes from a fusible link that comes right off the positive battery cable. It comes out of the fusible link and runs into a 2" long black plastic connector before the power wire goes to the relay. If you have power at the plug then the fusible link is good. You need to locate that relay. Mine has one fairly heavy orange wire (power from fusible link), a fairly heavy tan wire (power from the fuse box), a small dark green with black stripe wire (wire to temp. switch in the block) and fairly heavy red wire (power from the relay to the fan)on it.

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Z's r Best

 

hey thanks, that exactly what I needed to know. Thanks for all your help guys!