Cooling fan

Hi, I have a 94 Buick Century with a 3.1 engine and the cooling fan will not come on even after a 1/2 hour drive on the highway. The temperature gauge shows a reading between 1/2 and 3/4 but still no fan. The fan works when directly powered so I know it's not the fan motor and the temp. sensor has been replaced. I understand that after '87 the fans were controlled by the ecm. Could this possibly be the problem. Thanks for any help.

It is possible that the ECM is bad but it is also possible that the fans don't need to come on as the ECM has not read that the temp is high enough for them to turn them on. Do they come on when the AC is turned on? If so then they are probably working properly. If not then you may need a new fan relay to allow them to work correctly.

Thanks for the info. Could you tell me where the relay for the cooling fan is located. Although I have a Haynes manual for the car there is no mention or picture of the relays location.