ac on - no cooloing fans

Asked by GuruDBBVYP Nov 24, 2024 at 01:59 PM about the 2005 Chevrolet Monte Carlo LS FWD

Question type: Maintenance & Repair

2005 Chevy Monte Carlo 3.4L Same problem no fans with AC on, tested all
relays, fans and wiring working as intended. Missing neg ground to control relay
#1 from pcm. I need help moving forward?

1 Answer

157,895

I'm assuming you mean the radiator cooling fans? To test the PCM, wiring, relays, and fan motors in one shot you can do one of two things. With the engine off, unplug the coolant temperature sensor and then start the engine. The check engine light will come on, ignore it. The radiator cooling fans should come on at high speed immediately. If they do, the coolant temperature sensor is bad. If they don't, check for power and ground at the motors. If you have that, motors are bad. If you don't, start tracing wires and checking the relays. The cooling fans should also come on as soon as you select max a/c or recirculate, whichever you have on your control panel. The other thing to look at, before you start troubleshooting, is if the a/c compressor is turning on. If it's not, the fans won't come on with the system set to max or recirculate because you're probably low on refrigerant. When that happens the a/c system is disabled and the only time the fans will come on is when the coolant reaches a certain temperature. Usually around 210°F. Jim

Your Answer:

Own this car?

Share your experience with others.

2005 Chevrolet Monte Carlo

Review another car

CarGurus Experts

  • #1
    James Sparrow
    Reputation
    1,050
  • #2
    tenspeed
    Reputation
    990
  • #3
    John Saffrahn
    Reputation
    720
View All

Know more, shop wisely

Search

Related Models For Sale

Used Chevrolet Impala
209 Great Deals out of 4,430 listings starting at $1,995
Used Dodge Charger
806 Great Deals out of 14,431 listings starting at $1,300
Used Chevrolet Corvette
771 Great Deals out of 13,812 listings starting at $2,992
Used Ford Mustang
1,060 Great Deals out of 20,801 listings starting at $1,100
Used Chevrolet Tahoe
1,444 Great Deals out of 31,854 listings starting at $1,550
Used Buick Regal
57 Great Deals out of 769 listings starting at $2,999
Used Chevrolet Silverado 1500
4,349 Great Deals out of 122,255 listings starting at $1,995
Used Jeep Grand Cherokee
2,263 Great Deals out of 52,242 listings starting at $1,650
Used Chevrolet Silverado 2500HD
1,045 Great Deals out of 40,913 listings starting at $2,995
Used Ford F-150
6,740 Great Deals out of 173,357 listings starting at $1,900

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.