The fan will not come on as soon as the A/C is turned on...You can check it with a simple procedure. Just turn on the key. Next locate the red or green switch on the side of the drier bottle (located behind the driver's side headlight) and bridge the wires that are there. Do not unplug them, just jump a wire across. The fan should run, if so, you have checked 1/2 of the circuit. The other half is related to the operational temperature of the engine.
1992 500E (very soon I hope
1981 280GE SWB
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