2004 GMC Yukon SLT - Rear Air

[JochenWoern]

On my '04 YUK, the rear air is not blowing cold air.

Everything seems to work fine when it comes to operating the rear air, but it blows warm rather than cold air.

Any hints?

Many thanks in advance.

 

[Matt06Yukon]

Rear temperature acuator is not functioning perhaps.

 

[JochenWoern]

Rear temperature acuator is not functioning perhaps.

Many thanks.

So where is this unit located and how do I go at fixing/replacing it?

Thank you.

 

[NathanJax]

it's in the pass rear. It's really easy. there's a right up somewhere on here I'll look for.

Here's one, but it's not the one I was looking for...
http://www.tahoeyukonforum.com/forum/showthread.php?t=12635

 

[Matt06Yukon]

Its super easy to get to. Take off the rear passenger a pillar panel and then the fender cover. I have to switch mine every season, im actually in florida now and had to switch it back to a/c. Im getting kinda sick of this though and would like to just fix it. Anyone have the correct part number for the rear damper door actuator? I think its different and more expensive than any of thr normal front hvac ones. Every generic one ive tried hasn't worked.

 

[big_b_in_PA]

Ac delco #15-73506 control module kit, paid 65 on amazon last January. Works like a charm so far.

 

[Matt06Yukon]

Oh ok, that's not the one I was thinking about, what does that control? I was talking about the motor that controls the damper door, letting either hot air or cold air through.

 

[big_b_in_PA]

Oops, that's the control module, sorry, you new the actuator. I'll see if I can find it. I thought I replaced the actuator, apparently it was the control module instead. At least that was my problem.

Edit: I found the updated control module number, it is to replace the control module that was causing my issue, I originally thought my actuator was bad, but after some research, I figured out what was wrong. You may want to try taking the actuators and switching them between the blend and the vent actuator. That's how I figured out what my problem was.

Module number: 15832319

 

[JochenWoern]

Its super easy to get to. Take off the rear passenger a pillar panel and then the fender cover. I have to switch mine every season, im actually in florida now and had to switch it back to a/c. Im getting kinda sick of this though and would like to just fix it. Anyone have the correct part number for the rear damper door actuator? I think its different and more expensive than any of thr normal front hvac ones. Every generic one ive tried hasn't worked.

Please forgive my ignorance, but which is the rear passenger A Pillar Panel and which fender cover are we talking about?

Any more detail of HOW and WHAT to change would be apprecaiated.

Pictures possibly?

Many thanks.

 

[chauncey0337]

Jochen, the c pillar cover is the plastic cover inside the vehicle, just rear of the rear passenger side door-

The 'fender cover', which I have always referred to as wheel well cover, is located just rear of the c pillar cover. It's where the rear heat/ac unit is located.
Check this out and let me know if it helps-
http://tahoeyukonforum.com/forum/showthread.php?t=12635
Sorry, I just realized I posted the same thread as Nathan did.

 

[Matt06Yukon]

It'd be easier if I could post pictures from my phone. Passenger side inside rear pillar, the one with the tweeter mounted in it. Then unscrew that little black knob from the large plastic cover spanning the whole passenger side cargo area. There should one little push fastener to remove too. Then just gently remove that whole panel, it will reveal a whole seperate hvac system.

 

[mharders]

Mine was doing the same thing but only blowing cold air. I don't have a part number cause I never replaced it. I just turned it to heat manually for the winter. You just need to remove the rear plastics and you'll see what's pictured. The part you need to replace is #1

 

[JochenWoern]

Mine was doing the same thing but only blowing cold air. I don't have a part number cause I never replaced it. I just turned it to heat manually for the winter. You just need to remove the rear plastics and you'll see what's pictured. The part you need to replace is #1

Thanks everyone, I shall tackle this now accordingly.

 

[JochenWoern]

Thanks everyone, I shall tackle this now accordingly.

So, ....... Dealer diagnosed today that the actuator is broke, says the part cost 115 bucks and change.

I will purchase this part and will try to take care of this myself, as the dealer wanted 450 bucks installed. However, was wondering if there is a better write up with pictures available to properly take care of this issue?

Thanks in advance, your help is greatly appreciated.

 

[NC_John]

Everybody is anxious to jump in that back panel and put a new actuator in but it might be wise to get the Freon checked first. I redid all my air last year and it worked great. Then at Christmas, in FL, the A/C wasn't blowing cold. Turned out I lost most of the Freon through one of the fill/test ports (Schrader valve was leaking and the cap wasn't tight). I could see the dye all around the fitting.... I topped it up with an auto-zone quickie can and the truck was good for the rest of the trip. A couple weeks ago here I noticed the front was cold but the back was cool at best. I started poking around thinking it was the actuator but a mechanic friend said 'check the Freon level first.' My wife took the truck to work (GM dealership) and sure enough- it was down 1.5 lbs. They topped it up, couldn't find any leaks and now the 02 blows colder than my '13 sierra - front AND back.

Just might be an easier/cheaper thing to check first....

 

[JochenWoern]

Everybody is anxious to jump in that back panel and put a new actuator in but it might be wise to get the Freon checked first. I redid all my air last year and it worked great. Then at Christmas, in FL, the A/C wasn't blowing cold. Turned out I lost most of the Freon through one of the fill/test ports (Schrader valve was leaking and the cap wasn't tight). I could see the dye all around the fitting.... I topped it up with an auto-zone quickie can and the truck was good for the rest of the trip. A couple weeks ago here I noticed the front was cold but the back was cool at best. I started poking around thinking it was the actuator but a mechanic friend said 'check the Freon level first.' My wife took the truck to work (GM dealership) and sure enough- it was down 1.5 lbs. They topped it up, couldn't find any leaks and now the 02 blows colder than my '13 sierra - front AND back.

Just might be an easier/cheaper thing to check first....

Understood, ...... But dealer did open up the actuator yesterday and determined that the gear inside was broke.

 

[NC_John]

Understood, ...... But dealer did open up the actuator yesterday and determined that the gear inside was broke.

Yep, I saw- that's why the post was sent just in general. I didn't see anyone suggest doing that. I thought to check the rear actuator first before my mechanic buddy said check the Freon.

Now if I could get my front blend working better (seems to be a sharp difference between cold and hot rather than a full blend across the dial range). I hear that front is a ***** to work on so I'm living with it....

 

[JochenWoern]

Its super easy to get to. Take off the rear passenger a pillar panel and then the fender cover. I have to switch mine every season, im actually in florida now and had to switch it back to a/c. Im getting kinda sick of this though and would like to just fix it. Anyone have the correct part number for the rear damper door actuator? I think its different and more expensive than any of thr normal front hvac ones. Every generic one ive tried hasn't worked.

GM Part Number: 88891577

I paid $115.12 plus tax

 

[JochenWoern]

GM Part Number: 88891577

I paid $115.12 plus tax

Replaced the Rear Aux Temp Door today and Rear Air and Heat are working flawless.

 

[Red Rider]

Does anyone know the difference between the module assembly 15832319 and 1573506? The service bulletin refers to the first as proper replacement part, but when you look up on rock auto or amazon, the second part comes up as possible replacement. There is a difference of 20$ or so. Why the difference in price?