2004 ford f150 heating/cooling blower problem

[Crow Hunter]

All of a sudden position 1 on the blower switch does not blow air, the other positions work fine. Is this likely to be the resistor module rather than the switch? The resistor module is behind the glove box, correct? Thanks for any help.

[Jeremy airjer W]

If you have manual heater controls it will be pretty simple to check to see the low speed resistor is burned out. There should be four wires at the resistor. Unplug the connector. Measur continuity between the pin that the brown with white wire connects to and the pin the black wie connects to. If there is no continuity between those two pins than the low speed resistor is blown.

Since the other speeds work you can check for continuity between the brown with white pin and the other two pins to make sure you have your meter set up correctly.

[Crow Hunter]

Yup. Brown/white to black is open. Thanks Jeremy!

[Jeremy airjer W]

My pleasure!