Blower motor? Or resistor?

[stevew9983]

Hey guys I am usually not so easily stumped on this one but I am turning to you all for some input here. 2004 Grand Prix GT model. A very good friend of mine came to Advance and asked me for some help with her car. She said that her heater stayed on even after the car was shut off and she opened her door. She said it has been doing that for 2 solid days straight. The only thing she could afford to do was have me disconnect the blower motor itself so it didnt continue to keep running. Now we are starting to get colder mornings and she needs her heat fixed. She is an older lady with a fixed income budget who is just the nicest sweetest person to deal with. I felt kinda bad for her because the resistor is 81 bucks and the motor is 125 bucks. I am not sure as to which one it was because it didnt change speeds if you cycled thru them with the car off. When you start the car back up again it changed speeds when you changed the fan settings. Any ideas? Thanks in Advance for that guys!!!

[spoiledred94]

If it does in some settings change speed I think it would not be the resistor. I would think it would be the switch mechanism. My car would be very different. You could sort it out with the schematic. One other option is to postpone the diagnostics and hard wire a switch to power the blower at full speed. Just tie the input of the blower to 12 volts. $5 switch, some spare wire and an afternoon. Maybe a home cooked meal too.

[stevew9983]

I was thinking that too but then I looked at this blower motor resistor (from work so the new one) and it looks like it has like a module or something more than a traditional resistor would have. I am still thinking its the resistor its self but I hate to make this poor lady spend alot of cash for this part and it not fix it. I am just trying to help her out hopefully without several hours of chasing wires and all that fun stuff.

[spoiledred94]

hook up your volt meter and see if the voltage at the blower motor in changes voltage under different switch settings. Measure the resistor along the different taps. look for opens or shorts.

[willwren]

SpoiledRed, He can't measure resistance along different taps. It has a sealed module, not a resistor pack. It's not like your manual-control system at all. Let's not waste his time if possible.

Steve, go to the wrecker and get the module for about 10 bucks and change it. That's a very likely thing, and a good troubleshooting step all at once. Here are your fits:

Model Year Range RPO Code
Grand Prix 2004-2006 W
Grand Prix 2007-2008 W(CJ2,C67)
Impala 2006-2008 W(CJ3,C67)
Impala/Monte Carlo 2004-2005 W(CJ3)
Lacrosse/Allure 2005-2006 W19
Lacrosse/Allure 2007-2007 W19(CJ2)
Lacrosse/Allure 2007-2007 WC19(C67)
Lacrosse/Allure 2008-2008 W(CJ2,C67)
Monte Carlo 2006-2008 W(CJ3,C67)

The part itself is installed under the plenum, not on top like a Bonneville (sounds like you found it already though).