hello, i'm trying to troubleshoot the real reason why my radiator fan is not coming on. i originally wanted to install a manual switch to turn it on when i wanted to, but that obviously wouldn't work if the fan motor is burned out. i bypassed the relay, connecting the wires from pins 30 and 87 together, and i get nothing. i tested the pins with a voltmeter, and got a small voltage that slowly drains upon putting the multimeter in there. i have confirmed that there is 12V going into pin 30, so it should turn on the fan when you connect the wires from pins 30 and 87. so now i'm thinking either the fan is burned out, or someone else tried to troubleshoot and mixed up the wires at the fan.

does anyone have a pin layout for a 91 Jetta radiator fan? thanks.

 

There is a temperature sensor that signals the fans to come on when the cooling system gets warm. Your coolant sensor may be faulty or disconnected.
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