To me it is wrong that the fan runs all the time even when the car is cold ?
Disconnect the temp switch and it still runs.
Hayes book says with car not running and key in on position disconnect temp switch wire and short to ground should turn on fan it does not.
Thanks Hank
All the control is in the ground side and picking up a stray ground is easy in a 20+ y.o. wiring harness.
I'm not sure about the validity of that test since ECM logic is in the act and the ECM hasn't yet seen any evidence of engine operation.
Bob's right in mentioning the quickest/most simple item to check first. If that's not the issue, post here for the whole troubleshooting routine. Mention if the speedometer readings are in the ballpark and whether it's got Climate-control or Manual a/c.
-- pj
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