No rear air hot or cold

[tekkitan]

I am at a loss here. Replaced rear blower and the control module. Even the dealer is confused to what is wrong. In fact, they gave up and said they are waiting on a part and that was 10 months ago.

Here is what I am experiencing. No air is coming through the rear vents at all. No hot, not cold, no anything. The center console control for radio/read air, when I try to turn it on, just says "OFF" for a few seconds then the display goes dark again.

I have replaced my factory radio, but it was doing this before that so I don't think that's the issue. Anyone have any ideas or things I can check?

[bonedust]

find a better dealer for one...but is sure sounds like the control mod.

[tekkitan]

find a better dealer for one...but is sure sounds like the control mod.

yeah, it's where i bought it. it's a 2003 so i'm not going to another dealer to get it fixed. where is the control module you are referring to? do you mean the one in the center console? it seems the one that controls it on the overhead console does nothing as well. but i am not sure if that wouldn't work if the control module didn't work?

[tekkitan]

any more info on this control module is greatly appreciated. thanks in advance!

[east302]

It's a 2003 Tahoe LT, right? Here's a picture from mine (same model) taken a while ago. It has the auto a/c and I'm guessing your truck does, too. The black boxes with circles and numbers drawn to them are the damper actuators that open and close to let either hot/cold air out or switch from floor to ceiling. The black box in the middle with the two blue plugs on the bottom is the control module. It tells the damper actuators what to do and was (I think) about an $80 part at the time.

http://i463.photobucket.com/albums/qq360/rduaa_3312/IMG_9982.jpg

You say the rear control on the back of the console doesn't work? The front is set for AUX, when you try the rear controls, right? Does the radio function work via the rear control? What about the front controls?

You could throw parts at it all day, but I'd find another dealer. Since it's all electronic, they should be able to diagnose this for you. Their service manuals give them step-by-step methods for determining what is or isn't working.

[tekkitan]

It's a 2003 Tahoe LT, right? Here's a picture from mine (same model) taken a while ago. It has the auto a/c and I'm guessing your truck does, too. The black boxes with circles and numbers drawn to them are the damper actuators that open and close to let either hot/cold air out or switch from floor to ceiling. The black box in the middle with the two blue plugs on the bottom is the control module. It tells the damper actuators what to do and was (I think) about an $80 part at the time.

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You say the rear control on the back of the console doesn't work? The front is set for AUX, when you try the rear controls, right? Does the radio function work via the rear control? What about the front controls?

You could throw parts at it all day, but I'd find another dealer. Since it's all electronic, they should be able to diagnose this for you. Their service manuals give them step-by-step methods for determining what is or isn't working.

Yes 2003 Tahoe LT. When I attempt to turn the rear air on from the overhead console up front, the rear blower motor doesn't seem to even turn on.

Just to make sure, I set the controls up front to "AUX" and tried the rear controls again. No matter what button I push, it still says "OFF". The radio controls do not work because I have an aftermarket stereo and didn't buy the hardness to make the rear controls work with it.

I'd rather stay away from a dealer if at all possible, just bad experience with every dealer I have dealt with in my life so far. I suspect they did such a horrid job at getting it working is because they were doing it for free since it was one of the conditions of buying the truck. But I didn't get them to do it first because I needed transportation and I really just don't want to deal with them anymore :-)

Any tech help is appreciated, I know this is over the internet and is difficult. If I should be checking voltage or anything somewhere, I can do that. I don't want to pay $400+ for the dealer to fix this though if I can (hopefully) fix it myself for maybe less.

Thanks!

[east302]

I imagine someone here has a shop manual and maybe they can post the diagnostics. It may be available from alldata.com, but it's probably just a matter of checking voltages to see what, if anything is getting power.

In my case, the control module wasn't adjusting the actuators correctly, so guess I got lucky. Sorry I can't be more help, but you might try over at www.z71tahoe-suburban.com since it's all Tahoes and Suburbans.

[tekkitan]

I imagine someone here has a shop manual and maybe they can post the diagnostics. It may be available from alldata.com, but it's probably just a matter of checking voltages to see what, if anything is getting power.

In my case, the control module wasn't adjusting the actuators correctly, so guess I got lucky. Sorry I can't be more help, but you might try over at www.z71tahoe-suburban.com since it's all Tahoes and Suburbans.

Thanks for the help! I will check with them. I have an alldata account for my previous vehicle, I'll have to get it switched over to the Tahoe and maybe I'll find something.