The electric fan is turned on in low speed by the a/c system when the pressure of the refrigerant exceeds 20 bar (~300 psi). If yours comes on immediately, the switch (located at or near the receiver-dryer) or its wiring may be shorted. The fan should not turn on if the climate control is turned all the way off.

In your model, the aux fan can also be turned on in high speed by a sensor in the water jacket, if the temp exceeds 105C. If it is turning on immediately and especially if it does so with the a/c off, then that switch or its wiring may be shorted.

Both of these functions use relays that live in the relay box, behind the fuses. If the relay or its wiring has a short, you could get the same symptoms.

To check further, find and disconnect the wires from those switches, one at a time, until the fan stops. Then replace that switch with a new one. Ditto for the relays.

Let us know what you find.

Jeremy

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"Buster" in the '95

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