Help! Cooling fan problem!!

GMGUY2

Member
Joined
Mar 16, 2004
Recently got new motor in car, and while double checking fluids, connections, operation of everything I noticed my High speed switch that is wired to green/yellow wire on high speed relay would no longer work. I had a new Casper high/low switch and 2 new fan relays so I disconnected my old switch and installed Casper switch and both new fan relays. With ignition on I check high and low, both relays will click on and off but no cooling fan action. Manally checked cooling fan and it was OK. Checked the 3 pin connector plug going to cooling fan and NO power on any of the terminals!!!!! I don't think the car has to be running in order for the Casper swith to work. Need some ideas!!!
 
Not sure how your switch or the Casper's stuff works but here is the factory diagram. You may be able to troubleshoot from this and see how the modifications work to solve your issue.

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Ok thanks, stupid question, why does it show 2 high speed and 2 low speed relays or is that the same relay and they just separated them to show all the wires running to them?

So it looks like that since my relays will click on/off I have power to run the relays but not any current coming from the Red Fusible link to run the cooling fan, does anybody know where that fusible link is located?
 
I remember at one time I saw a complete diagnostic procedure for checking all the wiring and relays but can't seem to find it, anyone know where that is?

Thanks for all the help.
 
One is the load side of the relay and the other is the control side the relay. The portion that goes to the ground side is the control side of the relay. I believe you need to check the fusible links on the hot terminal at the starter.
 
Ok thanks, how can I tell if they are good or not? If its blown how do I fix them?
 
Does anyone have a good picture or a diagram of how everything hooks to the starter?
 
Update: Checked my starter wiring, I have the double wire fusible link and Battery power wire on the left starter stud looking from behind, and the single fusible link on the right stud. Fusible links are all good. I checked continuity and found that the single wire on the right stud goes to the relays, when I turn ignition on car off I do not have power there, so maybe I have the starter wired wrong or is my starter solenoid bad??? Can someone verify correct starter wiring or tell me if both terminals shoud have power with ignition on?
 
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Dang, go it figured out, aftermarket starter all the wires go on the left stud, right stud has short starter wire on it! Argggggg, thanks for all the help!
 
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