2007 Yukon Heat and Air on together

[ttrout]

Set on 72 both sides, passenger cold, driver side hot, help, Thanks

[DeltaP]

Could be low on refrigerant. Possibly a small leak.

[gmtech1]

Yep, either a low charge, or you have a bad temp door actuator.

[DeltaP]

I usually check the charge first. Easier and most likely.

[wayaboveme]

Had same issue in my 2000 Yukon except it wasn't blowing any heat. Replaced the actuator. I knew nothing about it and am sort of hands on and figured it out. The key info I had was I was hearing the actuator door close very loudly every once in a while so I knew it was defective.

[Cusser]

OK: mine's a 2005 Yukon Denali.

I only drive this a few times a year, Mrs. Cusser drives it most of the time. Summer 2014 coming back from trip 100 miles away, with me driving, the air out the vents changed from cold to hot by itself, at least on the driver side. I believe there was some clicking under the center of the dash too.

Anyway, mostly because of the noise, and I had similar noise and repair at a shop ($300) on the 1994 Suburban we had previously, I decided to take a look-see. Toughest part was removing the driver-most cover screw, needed a 7mm 1/4 drive deep socket, just crazy GM engineering (thanks, guys !!!). Anyway, I just got it in the AC position and disconnected the harness, as in Arizona we need AC tons more than heat, and Mrs. Cusser said she used the heated seat function instead anyway. I've left the cover off all this time too, don't really see a need to install that, and it doesn't show anyway; I've read some just reinstall the cover but leave out that ridiculous attaching screw.

Jump to Dec. 2015, I just ordered a replacement (aftermarket) actuator to repair this, like $50 online. I bought Dorman aftermarket replacement because the GM ones have a history of going bad, see that on the Internet a lot, and lots of replacement ones sold according to pages of online retailers. I just figured that I was getting old, and heat wouldn't be bad to have at times.

Once one installs the replacement actuator, you must follow instructions to get the GM computer to learn it (instructions online), like re-connect the battery and wait 15 minutes, then switch key to "on" and wait another 15 minutes.

[Cusser]

Originally Posted by Cusser

OK: mine's a 2005 Yukon Denali.

I only drive this a few times a year, Mrs. Cusser drives it most of the time. Summer 2014 coming back from trip 100 miles away, with me driving, the air out the vents changed from cold to hot by itself, at least on the driver side. I believe there was some clicking under the center of the dash too.

Anyway, mostly because of the noise, and I had similar noise and repair at a shop ($300) on the 1994 Suburban we had previously, I decided to take a look-see. Toughest part was removing the driver-most cover screw, needed a 7mm 1/4 drive deep socket, just crazy GM engineering (thanks, guys !!!). Anyway, I just got it in the AC position and disconnected the harness, as in Arizona we need AC tons more than heat, and Mrs. Cusser said she used the heated seat function instead anyway. I've left the cover off all this time too, don't really see a need to install that, and it doesn't show anyway; I've read some just reinstall the cover but leave out that ridiculous attaching screw.

Jump to Dec. 2015, I just ordered a replacement (aftermarket) actuator to repair this, like $50 online. I bought Dorman aftermarket replacement because the GM ones have a history of going bad, see that on the Internet a lot, and lots of replacement ones sold according to pages of online retailers. I just figured that I was getting old, and heat wouldn't be bad to have at times.

Once one installs the replacement actuator, you must follow instructions to get the GM computer to learn it (instructions online), like re-connect the battery and wait 15 minutes, then switch key to "on" and wait another 15 minutes.

Update on the 2005 Yukon HVAC system.

The AC compressor, tensioner, small belt I installed last August (and deslugger) all seem to be working fine.

Last year in my limited driving on that I had noticed that the AC changed by itself to heat on driver side, and there was clicking under middle of dash. One could stop and turn engine off and that would re-set. Apparently this is due to a faulty door/flap actuator under the dash, and is a common problem on Yukons, Suburbans, GM trucks. So I took off the underside cover, of course being GM the innermost bolt was like impossible to get to, dug out a 7mm deep socket and was finally able to get that (read posts about folks having issues with that, and just leaving that screw or cover off). Anyway, that actuator has 3 positions, and I got it into the AC mode and then unplugged the harness so we'd have AC. But it turns out that this meant no heat.

I got a new aftermarket Dorman actuator ($50, why buy more-expensive GM again when there is a trail of bad ones posted on Internet?), and I braved our 45F wind-chill yesterday to install it, actuator is held in by 2 hex head screws. Well, once again, cannot access one of the screws due to the center hump being in the way, what terrible engineering. The screws take a 5.5mm or 7/32 inch socket, and I had to grind down BOTH ends of the socket to shorten it (recessed, so no access to use an open end or box wrench, had to use the ground-down socket and a 1/4 inch ratchet wrench; no room to fit in a thumbwheel-type 1/4 inch ratchet either


Anyway, (using online instructions) I set the flap to align with the position of the new actuator, and bolted that in, reconnected the harness to the actuator, reconnected the battery, waited a few minutes, turned the ignition switch to on for a few minutes so computer could learn stuff, then switched ignition off for 10 seconds. So now we have both heat and cooling. I left the lower cover off, don't see any real reason to reinstall that.


Thanks again, GM !!!! What a poor design. I know a shop gets $300-$400 for replacement of these, had it done at a shop on the 1994 Suburban, and remember the mechanic saying how much of a pain it was !!!

[wayaboveme]

The design on the 2000 SLT must be a bit different since I didn't have the same difficulties in replacing the actuator. It wasn't easy by any stretch but it would have been a snap for you vs. what you went thru on your vehicle. Glad it's fixed for you now though!

[ttrout]

Was the temp door actuator, that screw was a challenge!

[Cusser]

Originally Posted by ttrout

Was the temp door actuator, that screw was a challenge!

Yep !!! Now there's two of us pi$$ed at the GM design !!! "Duplex" screws which have elongated hex heads at least would've allowed something other than a socket to be used, but still would've been a hassle.