One Cooling fan not spinning
#1
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One Cooling fan not spinning
Noticed that the engine is getting hot when spinning in traffic. the drivers side fan is not spinning. Can someone tell me how to trouble shoot. I know I will have to test the motor by putting 12v across it. Just wondering if the two fans are on two different circuits, or just one.
#2
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The fans are fed by dedicated feeders from the battery, one for each fan. They route through individual fuses in the CE panel. #28 and #29 in my 1989 car. No idea what car you have though...
Start at the battery positive, clean and tighten the several smaller wires that connect to the bolt there. Connect the two wires to the switch on top of the intake, and with the hood closed the fans should run at slow speed. Move to the CE panel, and VERIFY WITH A METER that you have good battery voltage on both sides of each fuse. The fuse has a little opening over each pin so you can stick a meter probe in there. Verify that the section of the fuse panel isn't melted while you are there...
Then, swap the two fan connectors and jumper those two intake temp switch wires again. If the running fan 'moves' with the swapped connectors, the motors are OK and you are chasing a controller or wiring problem. Start with that stuff and report what you find.
Start at the battery positive, clean and tighten the several smaller wires that connect to the bolt there. Connect the two wires to the switch on top of the intake, and with the hood closed the fans should run at slow speed. Move to the CE panel, and VERIFY WITH A METER that you have good battery voltage on both sides of each fuse. The fuse has a little opening over each pin so you can stick a meter probe in there. Verify that the section of the fuse panel isn't melted while you are there...
Then, swap the two fan connectors and jumper those two intake temp switch wires again. If the running fan 'moves' with the swapped connectors, the motors are OK and you are chasing a controller or wiring problem. Start with that stuff and report what you find.
#3
Pro
Thread Starter
Could not do exactly what you said, it is raining out side, and no cover. I did hook the non spinning fan up to a direct circuit, and the motor spins fine. I checked the fuses, they are good, I tested the continuity and I get a ground, and a positive feed. So thinking it is my controller by the passenger door.
I do have some discoloration on fuse 29. I will look at the circuit diagrams and see if that is it.
Is there a way to test the controller? also any idea on where a switched positive wire will be in the engine compartment? LOL what I really ned is a switched ground so I don;t burden the other circuit.
Also you are talking about the temp sensor at the back of the intake, not the one for the water jacket as the sensor I need to jump correct...
I have an 88s4 btw.
I do have some discoloration on fuse 29. I will look at the circuit diagrams and see if that is it.
Is there a way to test the controller? also any idea on where a switched positive wire will be in the engine compartment? LOL what I really ned is a switched ground so I don;t burden the other circuit.
Also you are talking about the temp sensor at the back of the intake, not the one for the water jacket as the sensor I need to jump correct...
I have an 88s4 btw.
#4
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Sounds like the fan control module.
A search by thread title would have found this:
https://rennlist.com/forums/928-foru...erational.html
A search by thread title would have found this:
https://rennlist.com/forums/928-foru...erational.html