Front Heat NOT WORKING, messed up.

[bob35josh]

Hello all, I'm new to the forum, so bare with me.

I have a 2003 tahoe LT. The front heat is jacked up, it has the dual climate control.

....some info....

there is plenty of coolant in the system.
the rear heat will burn your hand off (like it should)
there is no clicking sound when turning the climate control knobs (like i've heard of in my research, relating to the actuator(s))
I tried eliminating all white noise and putting my head on the passenger side floorboard while turning the climate control knobs, it sounds like there is a small motor or motors moving back and forth, no matter the position of the knobs. If it's set to 90, sounds like motor(s) moving back and forth. Set on 60 sounds like motor(s) moving back and forth.
The real jacked up part....if you leave the front climate control off for a while and turn it on to 90, it will blow hot like its supposed to, for about 10 seconds, then go to ~73 degree discharge air.
if you fluctuate the knobs, sometimes when you turn it to 90, it will get warm for 15-20 seconds, and go back to cold.
I've tried pulling HVAC fuses, unhooking battery for 30+ minutes. pulling RADIO fuse.

ANY help is greatly appreciated. It's starting to get chilly in the mornings.

Thanks to all in advance.

 

[bob35josh]

also...

another note: there seems to be more pressure coming from the vents when the control is set to a cold setting. There is still pressure on hot setting, just not as strong.

anybody?

help?

does anyone even have a diagram of the hvac system so i could find out what to test or look for to troubleshoot it?

 

[chauncey0337]

I'm not knowledgeable enough to help you on this but hang in there, I'm sure someone will chime in with at least a suggestion. Good luck.

 

[SunlitComet]

Is this automatic dual climate control?
I might be able to pull a rabbit out of my hat perhaps.

 

[bob35josh]

Yes it is automatic dual climate control. I like rabbits....

 

[SunlitComet]

Your automatic system has a boat load of temperature sensors any of which can be malfunctioning. However, the system is very "proper scanner friendly" and can give a boat load of live data that can narrow a problem fast. If a dealer service call is not an option then PM(you may need to make one more post first) your email address and I will send you all the technical stuff I have on it in PDF format.

 

[bob35josh]

got the email. thanks man I'll start doing some research and see if i cant figure this thing out.

 

[Bigmike613]

got the email. thanks man I'll start doing some research and see if i cant figure this thing out.

hey can i get that email too i have the same problem