I have a Pontiac G6 2006. The AC/heater blower only works on high. What could be the reason for this?

SOURCE: The heater / ac blower

It is the blower resister. I purchasted one at auto zone for $18.00. It is located under the passenger side dash. You need to remove the glove box and the plastic cover under the dash to expose the blower motor. the blower motor resister is right next to the motor. Simply unplug the resister remove the two screws and replace. I did this and now my fan works on all speeds.

SOURCE: Heat/AC Blower fan speed only works on High

Alot of people have the same problem with the fan switch and blown bulbs. There really is no fix for this. Jeep really screwed up when designing the heater control assembly. The cheapest solution is to buy another unit off Ebay. Can always go to the dealer but be ready to PAY for there mistakes.

SOURCE: Heat/AC Blower fan speed only works on High

hello, this sounds like a bad blower motor resistor!! its cheap and easy to change..if you need more info on locations let me know,, good luck.....marty

SOURCE: Heater blower switch only works in postions 3 and 4

Heat limiting capacitor is blown on low side. Limits excessive heat to components. Three capacitors on one board. One is constant. One runs two lower speeds and other runs two higher speeds. Need to replace. Follow wire from blower motor back towards center of vehicle. The capacitor is approx. 1.5" X 2.5" and is mounted with two screws. Simply remove plug and two screws, pull out capacitor. Replace with new in reverse order. Did last year. Part was relatively cheap and easy to replace. You do have to be somewhat limber to fingers and tools under there.
Good luck.

SOURCE: My heater and AC blower not working. Please help

In the fuse block,under the hood on top of the fender. Locate fuse #35 it's 40amp fuse for the blower moter. If the fuse is ok,there is another
common problem you can check. The blower moter resistor assembly,
located under the dash on right side. With a 12v test light check for
power to the blower moter from the resistor. If you have no power to the
moter, replace the resistor assembly. If niether of these works, I'll need
to know if you have climate control or manual control hvac. And for some reason, the wheel base. long wb or short wb. to dig any deeper.
But I hope one of the causes I've mentioned will cure the problem.
Good luck.