I have a 1993 Ford Escort. My husband recently rebuilt the engine. The cooling fan isn’t working. He relplaced the relay for the fan, but that apparently is not the problem. We have to take the car across the country in Sept. My husband thinks there is a problem with the electric wiring. Any other ideas?
Your husband is likely right. While I might guess the thermostat that controls the fan may be bad, it could be other things as well. If he has a circuit diagram he should be able to trace the path of the current (including the ground side) and find the problem. It just takes persistence. Replacing parts without really finding the problem can be expensive.
Check the fan motor. They don’t last forever.
All of the above . There are two relays to check , high speed and low speed. There’s a temp sensor. and to check the fan motor , use some test jumpers and hook 12v direct and it will spin at high speed if good.
The radiator cooling fan won’t turn on if the engine doesn’t get hot enough to need it. The radiator cooling fan should come on anytime the a/c is turned on (and actually works). There is a fuse and a fusible link. The fusible link may look like a fuse, or it may be in a fat section of wire.
The engine computer (ECC or PCM) controls the fans, through the relays, when it gets word of a hot engine, or the a/c being turned on.
Here are some wiring diagrams of the fan circuits to go with that digital multimeter you’re buying hubby for that special occasion.
Click on Fig. 7, and Fig.12. In Fig. 12, use the lower part of the diagram for your car. Remember, there is only electrical power to the radiator fans when the engine computer chooses. http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c1528008debf
unplug the CTS ,do the fans run? (coolant temp sensor)
the puter will default and turn fans on?