[Clayshooter]

The A/C fan speed control won't repond to speed changes. The fan stays on constant high even though the indicator shows it adjusting. Anything I can check to save me a service trip?

 

[GregH]

The blower motor speed controller has probably failed.

Swap another one in. It's located by the accumulator under the hood. Two 8mm screws hold it in.

 

[jimmy]

Some electronic fan controllers have an integral max speed relay and the contacts can fuse together and stick, tap it after you have selected lower speed to see if that does it. Still likely will need a new controller to fix it once and for all. Check fan current on max, if it uses too much current it will fail a new controller in time.