how to replace temperature sensor on a Pontiac 3.8 liter engine

Asked by Oct 28, 2014 at 09:42 PM about the 1999 Pontiac Grand Prix

Question type: Maintenance & Repair

cooling fans will not turn on no matter how hot the car yet if I
disconnect the temperature sensor plug the cooling fans will turn
onwith the engine running if I connect the plug back the fans will stay
on until I shut the car off when I restart fans will not turn on + air
conditioning is not working eitherwhen I try to turn AC on you do not
hear the clutches in the compressor engageand before I had work
done to my car the AC and the temperature gauge and fans work
properly that is how I got the car backit sounds like an electrical
problem or the e_c mI don't know but please any helpful information
would be appreciated it is giving me a headache I do not trust
mechanics anymore

4 Answers


Check the fan relay?

Best Answer Mark helpful

And on the ac,,check fuse,s and ac relay.

2 of 2 people found this helpful.

I forgot to list I also had my ECM reflashed so I believe there might be a problem with the ECM not communicating with the body module and there is also a fuse it is a 15 amp ignition fuse it is position 21 in the under hood fuse block I am NOT getting any power to either side of that fuse checked with meter checked with test light no voltage going to. The fuse is not blown can you please tell me where the source voltage comes from any help would be appreciated thank you for your reply


Fuse Position # 21 should be TRANS SOL - Torque Converter Clutch (TCC)

1 of 1 people found this helpful.

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