Q: Radiator Cooling fans not coming on when AC is turnd on

asked by on August 30, 2017

My cooling fans are not coming in when car is warm or when AC is on. I have a diagnostic manual and have checked both ECTs in the eng compartment. I have checked all relays (1 eng control and 2 fans) and they check just fine. I can apply 12 volts to the fans and they run. I have checked every fuse in car and under hood including the 30amp cooling fan ones. All are good. If I take the plastic top off The engine control relay and physically move the contacts of the relay, the fans engage and run with the AC on. So, I feel Like whatever controls the engine control relay is at fault. I actually put a new engine control relay in the car even though the old one tested fine and does not fix problem. Any ideas?

My car has 21900 miles.
My car has an automatic transmission.

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