Archived Heater Temperture Contol

[Haney]

I have a 2001 2500 QC 4X4. I have it sold Monday. The heater temperture control has quit working. All of the other controls work fine so I don't think it is a vacuum problem. I can switch to the defrost, vents and floor and can hear the vacuum switch fine. I took the control head off thinking it was a cable off and guess what..... no cable. It is electrical... . It is stuck on HOT no mater where the selector is at. I am assuming it is a bad control head or the door motor is bad...



Anybody got any ideas? Also, if someone with a 2001 FSM could read the part about how to trouble shoot this or email me a wiring diagram, I sure would appreciate it... .....



PM me, post here or send to -- email address removed --



Thanks,

Jamie

 

[wtrenholm]

Jamie



The temp actuator (electric motor) uses a connector that has spaces for six wires but only has three wires in it. Back probe the wires while everything is connected to see what is going on.



The three wires are:



1. DB wire- 12V from the ign switch. Should have batt volts anytime the key is on. Fuse #2 supplies the power, if this fuse is blown the blower motor won't work either as the relay will not energize.



2. YL/OR wire- temperature select. Should have a varying voltage as you rotate the temp knob.



3. BK/LG wire- ground. Should show 0V if the ground is OK.



The colors are from an 02 manual, hopefully they are the same. All three tests have the black lead of the meter are on the batt neg.



The actuator replacement procedure states you have to remove the dash and evap housing. You may want to test at the back of the control head. Here's that info also.



Take the 5 way connector that has three wires in it. The same three wires will be present. It used the same power feed, same ground point of G200 and the actuator wire.



HTH, I'll try watch for more questions if you post again.

Wayne