My 2002 cummins heater/air conditioner fan switch took a semi dump. All I have is the highest speed on the fan.

I checked out all the fuses and they all seemed to be okay. I replaced the switch and I still have the same problem.

Are there other electronics that I should be looking at or has anyone else had the same issue and what did you do to cure the problem.

Don

 

Blower motor rheostat will be your problem. (mounted a few inches away from the blower motor).

 

Thanks a bunch! Never thought of that. I'll check it out and post the results.

Don

 

Just got done installing the new rheostat. If I was 40 years younger with strong tiny hands it would only have taken a few minutes. BUT, being old and having really large hands it took me more than a few tries to get it out and the new in.

Works great and thanks again for the heads up!

Don

 

Don, you do realize that I'm never wrong.
And this will go to straight to my head and I'll be even worse. LOL!!

 

Go for it! You saved me a bunch of headaches on that fix. I'm going to drive all the way across New Mexico next month and now I can do it in comfort now.

Just a heads up to anyone interested I bought the part at AutoZone. They had it in stock. Unbelievable! )

Don

 

While you are in there pull the fan motor out and rotate it if doesn't spin freely you won't have enough air flow to keep the new rheostat cool and it will burn out again.