AC Doesn't Blow In Face or On Floor

[GSDunk]

I became the proud owner is a 2003 SLT about 6 weeks ago and only two times have all the air vents actually worked. (Dual climate control)

The 2nd time it magically decided to work, I was on the road and it worked great for the duration of the drive (about 1 hour)...but of course when I restarted the Yukon a couple of hours later, it went back to not working

The other 99.9% of the time when either the AC or the heater are on, the fan only blows air through the defrost vents.

Anyone heard of this?

(Without the back AC vents all aimed at my head, I'd be way more uncomfortable)

 

[ScottyBoy]

It's either the AC control panel in the dash, or the actuator up inside the dash that switches the functions back and forth. Best way to check that is to find a friend with a good dash AC control panel and swap with him for a day and see if the problem goes away.

 

[2011SSVHOE]

try a reset first, either pull the HVAC fuses or disconnect the battery. see what happens.

 

[GSDunk]

try a reset first, either pull the HVAC fuses or disconnect the battery. see what happens.

I'll try that first.....(and crossing my fingers it's that easy)

 

[GSDunk]

try a reset first, either pull the HVAC fuses or disconnect the battery. see what happens.

I disconnected the battery for a half hour and unfortunately this didn't help.

No big deal really. With such a great AC system in the back and being able to aim all the vents right at me, I'm cool as cucumber.

.....however, I would be interested to know what the fix is if anyone has had similar problems

 

[jaywoo65]

I had the same problem on a 99 Astro. Turned out it was a vacuum leak.

 

[RED TAHOE LS]

Geoffrey, previous post by jaywoo65 has a good point, vacuum leak. This is a sure way to check it, drive as normal with ac set and find a pretty steep hill an accelerate pretty fast and see if ac blows on the windshield or defrost ducts. If it does, you have a vacuum leak, check under hood for grapefruit size black tank with hose attached. JMHO and good luck.
David g..............

 

[mizzouguy]

None of it is vacuum controlled in an 03. All the actuators are electric.
EDIT: When you disconnected the battery, did you let it re calibrate before you started hitting buttons? Do this: http://sparkys-answers.com/2011/08/hvac-actuator-recalibration-procedure.html
If that doesnt work check this out: http://sparkys-answers.com/2011/02/2003-chevrolet-silverado-changing-mode.html
Should get you working again.

 

[RED TAHOE LS]

None of it is vacuum controlled in an 03. All the actuators are electric.
EDIT: When you disconnected the battery, did you let it re calibrate before you started hitting buttons? Do this: http://sparkys-answers.com/2011/08/hvac-actuator-recalibration-procedure.html
If that doesnt work check this out: http://sparkys-answers.com/2011/02/2003-chevrolet-silverado-changing-mode.html
Should get you working again.

That blows my theory, I have never owned one and did not know, my bad.
David g...........

 

[mizzouguy]

@RED TAHOE LS vacuum operated are the worst. Put a heater core in our 83 c10 suburban with a 6.2. After i was done i couldnt switch off defrost. Soooo many little bitty color coded vacuum lines and old rubber parts lol. Ended up being the exhaust manifold pressure switch and one piece of rotted vacuum line right by the vacuum pump. These newer ones are so different.