If there is no voltage coming out the gray wire, it is a direct output from the A/C programmer. The only thing additional you could do is check the continuity of that wire from the blower to the programmer to verify it is not open. You should be checking power at that wire with a voltmeter, as it is not always 12 volts, and a test light may not light even though there is power. It ranges usually from 4 to 9 volts.
Saturday, June 12th, 2010 AT 2:17 AM