Cheap6
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On at 104C, off at 99C is the low speed fan. High speed (+ low speed) is on at 112, off at 108C. V6.
The low speed fan is switched by the BCM, the high speed by the PCM.
To check the fan operation, remove the relays and connect a short length of jumper wire between the 87 and 30 terminal sockets for the relays. Do low speed first - the low speed fan should come on - put the low speed, 5-pin relay back, jumper across the high speed relay sockets and the high speed fan should come on.
To check the relays, if the first tests check out OK, put the relays back in but not all the way, so that you can access the relay pins. Connect each of the 86 pins to earth - body or battery terminal - the relays should click and the fans come on again.
To check the coolant temp. sensor and wiring, disconnect the temp. sender terminal, turn the ignition on and connect a 68 Ohm resistor across the temp. sensor connector. The fans should come on. If they do, the wiring is OK and check the sensor resistance - ~180 Ohms at 100C, which is close enough to operating temp..
The low speed fan is switched by the BCM, the high speed by the PCM.
To check the fan operation, remove the relays and connect a short length of jumper wire between the 87 and 30 terminal sockets for the relays. Do low speed first - the low speed fan should come on - put the low speed, 5-pin relay back, jumper across the high speed relay sockets and the high speed fan should come on.
To check the relays, if the first tests check out OK, put the relays back in but not all the way, so that you can access the relay pins. Connect each of the 86 pins to earth - body or battery terminal - the relays should click and the fans come on again.
To check the coolant temp. sensor and wiring, disconnect the temp. sender terminal, turn the ignition on and connect a 68 Ohm resistor across the temp. sensor connector. The fans should come on. If they do, the wiring is OK and check the sensor resistance - ~180 Ohms at 100C, which is close enough to operating temp..
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