It's a small issue, but one I'm trying to remedy. My fresh air blower only works on medium and high.(Could be worse, i guess) I'm trying to figure out where the problem may be. The blower motor obviously works. I think the switch assembly is okay, because if I rearrange the wires the two speeds still work but at different switch positions. I have voltage on the two wires for high and medium(white and white/green) when the key is on, but not to the remaining white/yellow wire. The only thing I don't know much about is the "bimetallic switch" in the blower motor housing.(Shown on "blown-up" blower motor housing in Electrical factory service manual) Is this what actually controls the blower motor speed and is that where my problem is? Anyone know if this single piece is available by itself?
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Anyone? Anyone?

clean the heater control switch in the dashboard...its filthy and sometimes the plastic melts over the contacts.

Rich

Make sure there are three wires( there are white with different colored striping) attached on the right of the blower switch. It helps if the radio is out.
Sometimes, one gets knoked loose during radio R/R. If all three are hooked up, switch them around to see if it's a bad contact. Been there.

Thanks guys. I have cleaned the switch contacts previously. I really don't think it's the switch. If I switch say the white/yellow and white/green, then medium speed comes on with the first position instead of the second position, so all three switch positions seem to be working. The motor and the relay at the fuse panel seem to be okay. The relay is a standard relay and not complex enough to control the three separate speeds. The "bimetallic switch" is the one thing I have no clue about. Is there anything else in the circuit I am missing?

On mine item #13 is two wire wound resistors which are for low and medium speed
on the blower motor. You may have a bad connection to where the resistors are
mounted to the plug in connector.