You can power it directly and nothing will happen. It relies on a digital speed signal from the A/C programmer, that comes in on the little gray wire. More than likely, you need a blower motor. Very seldom, in fact never, have I seen a failed programmer cause a lack of blower operation. Check that you do have power and ground at the blower, with a test light across the connectors large wires(red/black). If you have a light across that circuit, replace the blower motor.
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Thursday, January 12th, 2012 AT 4:07 AM