1991 themo fan switch
Thread Starter
Intermediate
Joined: Nov 2006
Posts: 49
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From: UCKFIELD EAST SUSSEX
1991 themo fan switch
Can anyone please tell me where the thermo fan switch for the engine coolant fans is located please. My 1991 is overheating and the fans are not coming on so I am trying to get the fans to run all the time so that I can take it to the garage to get fixed. Hopefully if I find this sensor I can run a bypass to get the fans to work.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
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From: San Diego, Ca
There isn't one. Fan Relays are driven (grounded) by the ECM which gets it's temperature signal from the Engine Coolant Temp Sensor. The '91 should be doing that for the main fan with a temp signal of 226 degrees, the secondary at 228; or when the a/c pressure sensor on the a/c high side line indicates something in the neighborhood of 200 psi. Grounding the diagnostic link should crank on the fans. Otherwise, find the ECM side of the Relays and provide a separate ground, or simply call a tow truck.
Thread Starter
Intermediate
Joined: Nov 2006
Posts: 49
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From: UCKFIELD EAST SUSSEX
Thank you for your reply.Been wondering why I could not find it .The Haynes manual is therefore incorrect. I did get the fans to run with the ALCL grounded. It is possible to drive the car while in the diagnostic mode ?
