Electric Fan Question...Help
Thread Starter
On The Tree
Joined: Mar 2011
Posts: 131
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Electric Fan Question...Help Hello, maybe someone can give me some advice.
94 LT1 T/A . When I bought the car, the owner had the ECT sensor unplugged so the fans stayed on cause the car was running hot. That made the car hard to start and drive shitty so I replaced the ECT sensor in water pump. The SES light went off and car ran great...Now the fans dont turn on at all though and car runs super hot. Today, I tried swapping the U/H relays which did nothing. I jumped pin #2 to ground on cooling fan #3 relay that turned on high speed fans. I dont think that turning on the AC will trigger fans because had a refrigerant leak and previous owner disabled AC . I have a feeling that the comuter is not commanding the fans on. Does anybody have any advice. Thanks alot
94 LT1 T/A . When I bought the car, the owner had the ECT sensor unplugged so the fans stayed on cause the car was running hot. That made the car hard to start and drive shitty so I replaced the ECT sensor in water pump. The SES light went off and car ran great...Now the fans dont turn on at all though and car runs super hot. Today, I tried swapping the U/H relays which did nothing. I jumped pin #2 to ground on cooling fan #3 relay that turned on high speed fans. I dont think that turning on the AC will trigger fans because had a refrigerant leak and previous owner disabled AC . I have a feeling that the comuter is not commanding the fans on. Does anybody have any advice. Thanks alot
Thread Starter
On The Tree
Joined: Mar 2011
Posts: 131
Likes: 0
Thanks Fex. I think that the ECM as the ability to ground the relay because when I plug in the code reader it turns on fans like its supposed to. I checked the 3 relays and all have power and ground where they are supposed. I dont have a scanner to see if the computer is telling the fans to turn on or not. Antifreeze is filled. Possible that there is an air bubble at ECT sensor?
TECH Veteran
Joined: Dec 2008
Posts: 4,147
Likes: 62
From: Little Rock, AR
You need a scanner. The code reader that you are using will cause the fans to come on, but it won't work for getting any codes. That obviously proves your fans/fan circuitry is ok, though. If a/c is disabled, the fans won't come on when you turn a/c on.
