Cadillac Repair: vehicle blower not operating, cadillac seville, voltage signal

Question
I have a 1997 Cadillac Seville SLS northstar engine I turn on heater and the car didnot heat up.  I didn't hear fan operating.  Could this mean that the blower has gone bad or could there be some other problem. I was told that if the freon is low it would shut down fan.  I was also told that it could be a module.  HELP!

Answer
Hi William, Most times if the blower motor won't turn on on any position it will need to be replaced. You need to check for power and ground at the motor and for a voltage signal on the third wire. If those all check out then the motor is bad and the reason it is so expensive is because the module is inside fan housing. Low freon will not keep the fan from running...however if the outside temp sensor is reading below 60 degrees then the a/c won't engage and the coolant has to get heated up some in order for the fan to turn on in heat mode. If on defrost then the fan should turn on with-in 10seconds of starting the car. Hope that helps. Bill