My cousin'* car...he says that the blower used to work on the highest setting, now it doesn't work at all...also he says that he used to be able to switch between floor-defrost-vent, etc, and now that doesn't work either.

My first impression was that it'* the blower motor...but with the other thing not working i'm not so sure.

Where should I start?

Not sure if it applies..but the 00 GP'* had a module that would frequently go bad and you'd loose all but high fan speed. Might start there and see if the blower motor is not burned out.

If it'* an older car, it could be the resistor block. When they go bad, they tend to lose the lower speeds and the highest speed, since those circuits get the most use.

my brother'* 98 gp had the blower motor resistor go bad and only had the high setting. replaced it and it was fixed.

http://www.bonnevilleclub.com/forum/...ic.php?t=90643

Just went through the same thing with my brother'* 03 GP GT. Good links contained within.