Questions and Answers
Sunbird Cooling Fan
Q. Hello Vincent. The electric cooling fan on my 1994 Pontiac Sunbird won't turn on automatically or continue to run (as needed when the engine is hot) when the ignition is turned off. It'll turn on with the A/C actuated and will turn on and off with the engine running as triggered by the temperature sensor.
I replaced the fan relay but that didn't fix it. The engine is a 2.0 liter, 4 cylinder, fuel injected, automatic transmission, with A/C & ABS. 67,000 miles on the clock. Any suggestions?
Sincerely,
J.C.A. This one may be a bit tricky for a do-it-yourselfer, however this is what I would do. First understand the fan is triggered to come on at approximately 227 degrees. Since the fan comes on in A/C mode, the fan and most related systems are intact. I would ground the "A" and "B" terminals at the diagnostic connector with the key on and engine off. This will trigger all the drivers in the ECM on. The fan should run. At this point if it runs look for a two wire coolant sensor out of calibration. Finding it and unplugging it will send the ECM in to a safety default and the ECM will turn on the cooling fan also setting a check engine light. If the fan doesn't come on and the check engine light stays dark, replace the ECM because its shorted internally.
Additional Information provided courtesy of ALLDATA
