Most of the time the fan works fine on all settings but after the truck warms up it will only blow on high. When I set it to anything lower than high the a/c light goes out and the fan shuts off. This is bad considering Ohio summers are crazy hot and humid lol. Any help would be great.

 

i think the way this works is that there is a resistor inline with the fan. on high, the resistor is bypassed so the fan gets full voltage and runs fast. on lower settings, the current passes through a higher level of resistance, and passes less voltage and/or amps.

look for "blower motor resistor"

 

Just searched that and couldnt find any threads with answers. All I could find were where some people had replaced the resistor and still had the same problem.

 

This site is awesome, always a useful tool. I had this issue. Replaced resistor, and cleaned all the leaves/pine needles/dirt from behind it aaaaaaaand BAM! fixed! $40.00 part and 5 minutes work solved a problem I've had for months......if only i had found this site way back when problem started

 

If it is cutting off the snowflake light, I would suspect the switch itself. If it was staying on and the blower didn't blow, I would suspect the resistor pack in the ductwork.