Greetings, I have installed a new engine and trans in my '89 4.0. Yeah right?
I'm having multiple problems one of which is my auxiliary fan will not turn in. I checked it and it works once directly jumped and I replaced the engine coolant sensor, the coolant temp sensor and the relay. The wiring seems ok and I'm about to check the relay housing for continuity.
Apparently I could unplug the coolant temp sensor on the block and the fan should start.
My real confusion is whether of not the ac needs to be charged, I read it both ways. Whats the truth?
I'm having multiple problems one of which is my auxiliary fan will not turn in. I checked it and it works once directly jumped and I replaced the engine coolant sensor, the coolant temp sensor and the relay. The wiring seems ok and I'm about to check the relay housing for continuity.
Apparently I could unplug the coolant temp sensor on the block and the fan should start.
My real confusion is whether of not the ac needs to be charged, I read it both ways. Whats the truth?
CF Veteran
Aux cooling fan does connect to coolant temp sensor its run by the fan switch on rad.Unless temps up around 218 degrees it wont come on. If you jump low pressure switch on Ac it should come on.
CF Veteran
This can also help.http://www.lunghd.com/Tech_Articles/..._Diagnosis.htm
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May 16, 2024
- Join DateAug 2011
- LocationPrescott, Az
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- Year1990
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Quote:
I'm having multiple problems one of which is my auxiliary fan will not turn in. I checked it and it works once directly jumped and I replaced the engine coolant sensor, the coolant temp sensor and the relay. The wiring seems ok and I'm about to check the relay housing for continuity.
Apparently I could unplug the coolant temp sensor on the block and the fan should start.
My real confusion is whether of not the ac needs to be charged, I read it both ways. Whats the truth?
Originally Posted by bob of the rockies
Greetings, I have installed a new engine and trans in my '89 4.0. Yeah right?I'm having multiple problems one of which is my auxiliary fan will not turn in. I checked it and it works once directly jumped and I replaced the engine coolant sensor, the coolant temp sensor and the relay. The wiring seems ok and I'm about to check the relay housing for continuity.
Apparently I could unplug the coolant temp sensor on the block and the fan should start.
My real confusion is whether of not the ac needs to be charged, I read it both ways. Whats the truth?
Unplugging the sensor at the back of the head will have no effect. The sensor in the radiator turn the fan on at 218*
CF Veteran
The wires for that E-fan temp switch in the left side if your radiator are right there by the air cleaner. You can connect the engine side (jump those two),and see if it comes on. It's relay is alone on the left inner fender btw. Also it should come on with defrost, as well as AC, (if the AC is working I guess). X3, about 218* is when it comes on.