cooling fans run whenever the car is running?

2001 BUICK PARK AVENUE

147,000 MILES • 3.8L • V6 • 2WD • AUTOMATIC

R.LATOUR

MEMBER
4 POSTS

Hi, the cooling fans run whenever the car is running. I have changed the coolant temperature sensor and the fan relays #31, #34 and #35 but the fans still run whenever the engine is running.

Jan 23, 2024 at 8:38 AM

STRAILER

✓ASE Certified Mechanic
54,832 POSTS

Do the fans run when the HVAC system is off? If so the fan control driver inside the PCM has gone out. Here are the wiring diagrams so you can see how the cooling fan system works and the location of the PCM. You can get a rebuilt unit by searching google or Ebay. Check out the images (below). Please let us know what happens.

Images (Click to enlarge)

Professional Diagram for 2CarPros Members
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Jan 23, 2024 at 11:20 AM