2003 Buick Century

Engine Cooling problem
2003 Buick Century 6 cyl Front Wheel Drive Automatic 100k miles

i just replaced the thermostat, radiator cap, coolant sensor, and checked all relays on my car and the cooling fans still aren't coming on when the car reaches normel temp. And then it starts to go past the normal temp and the fans won't come on but when I unplug the coolant sensor or turn the air conditioner on both fans come on is there another sensor, switch or anything else that controls the fans if so what and where is it located. Please respond asap and by the way nothing is stoped up
September 25, 2010.

3 cooling fan relays and an engine coolant temperature sensor are easiest and cheapest on the circuit that could cause this issue. If they have been checked/replaced already than all that is left is the powertrain control module (PCM).

Sep 26, 2010.