Tring to fix my rear HVAC. Hot/Cold change over not happening

[wade]

2003 Denali

I bought the rear blend door actuator. Still no worky. It doesnt rotate either way when plugged in.

When I manually turn the knob itll blow hot or cold depending on which way I turn it.

So... why isnt it working, is there a TSB?

Bad wire? fuse?

 

[chip]

These are good questions. I am (or WAS) in the same boat (not sure which). I replaced my actuator and thought the same thing, but we (you and I) MIGHT be mistaken. I've been struggling with this for a while, because it will blow hot sometimes, just not right away. Maybe we can figure it out together?

 

[wade]

I ended up ordering the NON-Auto climate control one, it has a different pin out. New one is on the way, stay tuned!

 

[chip]

Interesting. Let me know how it goes.

 

[wade]

Its weird. I plugged my new incorrectly ordered unit on my truck, and as you know, it didnt work. But It did work when I plugged it in my buddys tahoe that doesnt have the auto climate control, which was to be expected. But... when I unplugged my unit from his truck, the actuator was turned one way on the (hot) side and when I plugged it in my truck again, my truck automatically turned it back to the (middle, default) position, but wouldnt control it anymore.

It all comes down to that I DID order the wrong unit. There is 4 pins all in sequence on the non-AUTO climate device and on the AUTO climate device it is 3 pins in sequence then a open space, then 2 more pins in sequence.


THe new piece is on its way

 

[chip]

That's interesting, because mine only has 4 pins, but I DO have auto control, and I know I have the right part #. Can you post a pic of where this actuator is placed in the back (There is more than one back there)?

 

[wade]

Ill get a pic , thats off you have AUTO and 4 pins. What year, truck u got

---------- Post added at 11:34 AM ---------- Previous post was at 11:31 AM ----------



1- Hot/Cold actuator
2- Floor/Ceiling actuator
3- Control module #15832319 with the two blue clips



My buddys NON AUTO climate Tahoe doesnt have part #3,

My denali DOES

 

[chip]

2003 Yukon.

I cold be wrong, so don't hold me to that, but I think I have 4 pins. I'll go check if I have to.
.
.
.
.
.
.
.
.
You know what?!?!?! I think we might both be looking at replacing the control module! Shit, I hope not!

 

[wade]

well I may not have to. I hope the correct part works. I know that when I used my buddys tahoe to control my incorrect unit, that when I plugged the incorrect unit back into MY denali, my truck DID turn it to the middle setting. Showing it atleast does get power.


What makes you think maybe the control unit??

If my new correct part doesnt work, I will order the control unit, no biggie.

---------- Post added at 02:29 PM ---------- Previous post was at 01:32 PM ----------

Update:

Well since I thought my hot/cold blend actuator was dead, I found it it was NOT. Its the same part that actuates the ceiling/floor blending. So I took the Hot/Cold blend actuator that I "thought" was bad and I swapped it into the Ceiling/floor control and it WORKED flawlessly.

So, seems that now I know both actuators work, then its gotta be the control module correct?

 

[chip]

I think you may be right! Shit, I can't believe that hadn't occured to me sooner. I should have tried what you did. Just goes to show, two minds are better than one!

See if you can get a deal on 2. If you can, I'll go halves with you.