Cadillac Repair: 1991 Cadillac SedanDeville 4.9 V-8, purple wire, charles willis

Question
I am writing this for my husband, Charles Willis.  We have a 1991 Cadillac SedanDeville, 4.9 V-8.  The air conditioner and heater fan will not shut-off.  How do I correct this problem?  Thank you for any information you may know on this problem.

Answer
Hi Nancy, Usually what happens is the power module for the blower motor goes bad because the blower motor is useing too many amps to run and that shorts it out. The module is located under the hood on the passenger side up by the firewall in the blower motor housing. If you replace the blower motor and module as a pair then you should be ok. If you just replace the module then you might be back to having the fan run all the time in a short time. To keep the motor off until you get replacement parts just remove the connector on the module that has the big purple wire in it. Then when you drive the car plug the connector in. Hope that helps and makes sense. Bill