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99 Grand Prix GT Cooling fan issue

Patrick McDade

New member
I have a 99 GT 3.8L Naturally Aspirated, and I wanted to know if there is a separate temp sensor for the cooling fans other than the one in the thermostat housing. From what I understand, the one in my car is a 3 pin, which leads me to believe that there isn't a secondary sensor and one pin sends info to the gauge and another pin sends info to the PCM. I have checked all the relays and fuses for the fans and nothing is wrong there. Both fans work constantly when I have the A/C running but wont kick on otherwise. Thanks in advance for any and all help.
 


While I can't b e of any specific help, I can offer that on my 2000 GT, both fans run all the time, AC on or otherwise. As soon as I start the car both of them are on no matter what.
 
let your car idle for 15 minutes or so, once the temp gets to the 1/2 way mark they should come on. chances are you cant hear them while driving the car, and if you not overheating, they are working.

im not 100 % sure but i think i read they dont come on till the engine hits 212 deg.
 
its not always proven good when you order that good part number for temp sensor. mine hits 226 and high speed fans come on, but gauge says its pushing 238...i think THATS my problem. bad temp sensor range that goes to gauge.
 
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