1992 Ford F-150 • 255,000 miles

We have been having problems with our heater. We finally found and fixed the air temp problem, FINALLY. Hot air. Now we need to figure out why the airflow control switch only works on low or max high. Please someone help me, help my husband fix this problem.
Terry Bissett
November 2, 2012.

The blower motor resistor may be failing. Either that or the switch at the control panel is going bad. More than likley it is the resistor.

Thank you for you help, maybe you can instruct me on if I can test the resistor and how to do that, or should I just replace it. Also is the blower motor and the blower motor resistor two separate parts?

Nov 2, 2012.
You will have to get the spec on the resistance for the motor resistor and it is not always published. Most of the time it is easiest to rplace the resistor as they are genrally less than $20. Try going to to get one as they have extremly good prices on well known brands and have a great reputation.