Hello. I've the above vehicle in which the blower is stuck in one mode - possibly high - no matter where the switch is set. Blows constant whether it's on off or 1 - 5. Info I saw in the web led me to believe it was the resistor. I just finished changing out and I still have the same issue. Anyone have any ideas of what the problem could be?

 

Does the blower run with key off? How about with the HVAC Blower fuse pulled from the I/P fuse block? If both are affirmative, the relay integrated into the blower motor resistor assembly is probably stuck on. New parts don't always mean working parts. If that's not the case, the switch on the HVAC control head has a short.

 

No, key has to be in on position for the blower motor to run. Just check out the switch control and it appears to be turning to each position. If it is the switch, what kind of job is it to replace or fix?

 

Replacing the HVAC control module without marring the trim panels around it can be tricky. Before you attempt it, you may want to make sure the electrical connector is getting the proper power as follows:

Terminal A, TAN wire, hot when fan **** in 2
Terminal B, YEL wire, hot when fan **** in 1
Terminal C, PPL wire, hot when fan **** in 4
Terminal D, LT BLU wire, hot when fan **** in 3
Terminal E, BLK wire
Terminal F, ORG wire, hot when fan **** in 5
Terminal G, ORG wire, always hot

Take the electrical connector off the blower motor resistor assembly and then measure the voltage on each wire against a known good ground. There are five wires that should be hot exclusively one after another as you turn the fan ****, e.g., only the yellow wire should show voltage among the five with the fan **** in the first detent, etc. If they check out, the problem is still the blower motor resistor assembly.

 

Just over the weekend the blower quit working. It went from running all the time regardless if the switch was on or on any of the 5 speeds to not running at all. Now it's become a more dire need to fix. Although its been in the 60's and 70's, we could get some winter weather yet. Any ideas?? I've tried replacing the resistor as mentioned earlier. Is it possible that the blower motor is the culprit? Or would that either run or not run?

 

It sounds like you didn't do anything I suggested in my post #4. Consider taking it in for service.

 

Time to revive an old thread rather than start a new one, which I hope helps others in the search and pertains to this thread.

I am working on a 2003 Venture where the owner (a friend) describes the same thing. It went until only the high was working, then nothing at all. I hooked a meter up to the blower wires. If I wiggle the fan control on 2 and 5 I get a reading. I pulled the control assembly out, and found burnt wires behind the control. I got the plug out of the control to find two contacts were out of the socket from the plastic melting. It needs a new control and a new plug.

Would a bad resistor cause it to get too hot? I heard relays within the resistor which is different than just having springs, so this is a little new to me.

 

I have found the issue to be melting of a terminal in the fan blower switch. I will get another and instal it. However the terminals you speak of are not marked as far as I can see. There is four on the left and three on the right.

 

@Alternative....I get power in the wires to the resistor, resistor is new. blower still doesn't go...Now if everything is connected, and turn the switch into 1..the complete switch panel goes dead...all the 4 pushbuttons go out/do not work...if I go back to the off position...the 4 buttons start to work after 10-20 seconds....Did you had the same issue?