Pontiac Repair: 91 GMC Jimmy v-6 4.3 ltr, gmc jimmy, purple wire

Question
Heater/ac blower motor not working suddenly..and fuses check ok? Now what? Thanks Bill

Answer
Hi Bill:

first off this is a Pontiac repair forum but I can help you out. with the key to the on position turn on the blower to hi speed and check the purple wire at the motor with a 12 volt test light from that wire to ground the light should light BRIGHT. if so try it on the other speeds is should be dimmer on the lower readings. If that is all okay check the ground wire on the motor it's the black one. check that with the test light from that wire to battery (+) the light should light bright. If the purple wire has no power to it you have to trace it back to where you are loosing the power it could be the resistor in the heater box or the HI blower relay or the switch. good luck :)