heat/ac blower won't turn off

ofbsac916

My blower motor will not shut off unless I disconnect the wire to the blower
Do I need a new blower switch? and where can I get one?

Mr_Shiftright

Maybe, maybe not. You should remove the switch first and test it to be certain.

You might try here for parts (just a pointer, I don't know this vendor):

http://www.pontiacparts.net/

imidazol97

If I may jump in and hope the poster reads this, since there's no year given or model, I don't know if this might have electronic blower motor speed control or if it's a system using resistors and switch that clicks from setting to setting.


In Some GM cars, the blower control module for the automatic speed control quits operating correctly and may not shut off the blower motor power. Sometimes the speeds on the electronic control settings go "strange" from what the 4 speeds used to be.


On the manual system using the resistors there are two relays on some GM systems where the power is turned off by one relay and the speed is controlled by the switch through the resistors. AND there's a second relay that can switch settings from regular contact to a power wire to supply direct power from a fuse that's 30 amps to the blower for high speed instead of going through the resistor unit.


One thing to try might be looking in the owner manual for the fuse box locations, there may be one under the hood and inside the car. On the manual or inside the covers will be diagrams of which fuse is which--with very short abbreviations. On relays that may be connected to the blower motor and its power, given them a sharp rap with a screwdriver handle. Sometimes a relay burns the contacts and sticks so it can't release back to the normal position.


The blower control module I mentioned above can be gotten from recycled pick and pull cars. Check model number on rockauto.com and a blue link in their description will list all the vehicles sharing that part.


But this needs diagnosis to decide where the problem is. Throwing parts on may get expensive, unless you're a do-it-yourselfer with a pick-n-pull junkyard near by.