The blower motor is constantly on high. I have to unplug the plug to the blower motor to turn it off. Temperature controls work fine. OFF button does not.

I did the DIY for the blower motor subharness thinking that the wires shorted and fused together causing the blower motor be to stuck on high, but that was not the problem. So I removed the updated subharness.

I searched and read through a few threads and there were 2 threads with similar problems, but no fix was posted. And most threads I found were about the blower motor not working.

Control Transistor? If it is bad, wouldn't that cause the blower to not work?

I'm stumped and can't figure out why the blower stays on constantly.

Any ideas?

Thanks.

 

Sounds like the OFF button controller stops working.

 

^^^Thanks.

Know how to test it, other then pushing the button?!

 

Maybe the transistor has shorted- take it out & test it.

 

^^^Thanks.

If the transistor shorted, could it cause the motor to stay on? I figured if it was bad, then no power should be getting to the motor.

 

Generally, yes.

 

maybe the power connector under the blower is shorting itself to On?
been a lot of those melting recently

 

Thanks!

It was the Control Transistor. Changed it and everything is working correctly.

 

Great- so it was shorted?

 

^^^Yes.

I didn't test it to be sure, but when I opened up the transistor the board had burned spots and a slight smell of melted plastic.

Thanks again for the help.

 

did you ck the power connector for damage- melting- loose wires etc
that is what usually preceeds the transistor failure

 

I did and the plugs/wires looked fine. Since I do have the updated sub-harness, which I installed and un-installed, I'll re-install it again just to be safe.

Thanks

 

thats the best plan- its updated for a reason