VictoriaR

I have a 2016 Chevrolet Suburban LT. When I turn the heater on the front will blow hot but the back not so much. When I turn the AC on the front will blow cold but the back not so much. I took it to the dealership and they replaced the rear heater core, recharged the ac system and vacuum bled the cooling system. When I picked up my vehicle I still had the problem. What else could it be?

Cusser

Is the issue that the air FLOW in the rear is less than it had been?

VictoriaR

That and the heater in the back isn't blowing the same temperature as the front if they're both on high and same thing with the ac. The ac in the front will blow at 40-45 on all the way low and the back is 65-70. Heater in the front will blow at 140-150 on high and the back will barely reach 90. And the back will only blow out if it's on the way high anything lower it you can't feel it unless your hand is right on the vent.

repairman54

There is an actuator in the rear unit as well as temperature sensors to control its output.
Take it back as it's not working properly. Maybe the tech forgot to plug in a connector.

VictoriaR

I took it back, they had it an additional 2 weeks and it's still having the problem but now when I turn on the ac or heater it blows on the floor instead from the top.

Cusser

Sounds like a bad actuator to me !!!

VictoriaR

Air door actuator? I was looking into that and it seems like an easy install. They had my car for 3 weeks total and changed the rear heater core twice and still couldn't figure it out.

Cusser

Victoria - our 2005 Yukon Denali sunroof had an intermittent and sometimes would not close (no hum or anything). I checked the switch continuity and it tested OK. Our local ASE independent mechanic said these were complicated, to take to dealer. Using information from radio show mechanic, I told dealer that I would pay for a fix, but not for guessing; and I wanted any of my parts retained for me. Dealer advisor later called and said it was a bad switch and it was fixed, about $250 (after I protested about the $50 hazardous waste fee, since NOTHING at all had been discarded). As radio show guy said: I paid with a credit card. Picked up vehicle and NEXT DAY it failed to close again. Anyway, multiple trips to dealer failed to fix it or find why it was bad. Dealer actually told me "we have no idea what is wrong", nice !!! I had posted online to see if others had this issue, and a GM rep picked up my thread, and I was finally able to get a refund (didn't need to have credit card company get involved to reverse the charges).

The dealer also "recommended" new radiator hoses even though mine still had the aftermarket labels on them from my install, and my aftermarket hose clamps; I imagine that they never even opened the hood for this, was just fishing for additional business.


Our own 2005 Yukon Denali had 3 electric actuators under the dash, and one went bad. R&R for me was a pain in the butt to get the lower dash cover off, I had to grind a 5.5mm socket shorter at both ends to fit. Actuator replacement was easy (I used a Dorman part) but one has to use the involved procedure to get the vehicle computer to recognize it.

An actuator also went bad on our 1994 Suburban, cost me like $400 for mechanic to fix that.

VictoriaR

Should I take it back or somewhere else and tell them to change the actuator? Should I reach out to GM?

Cusser

If you paid the GM dealer for a fix, they need to fix it (at no additional charge), sounds like they were guessing. So I surmise that they charged you a lot for parts and labor for stuff that didn't fix the problem, pretty much fraud.

Or dispute the charge with your credit card company, tell them dealer charged you but did not fix, and won't "play ball". Then go to an independent ASE mechanic shop; folks like to believe that dealer has special knowledge and skills, but that typically isn't true.

By the way: we no longer have the Yukon with the non-closing sunroof. On a day that the sunroof "decided" it would close, I simply removed its fuse. Sold it at 240K miles, new owner didn't care. New owner also didn't care that the windows in the rear doors were inoperable so just raised and held in place by sheet metal screws. One of the issues on modern vehicles is that the electronics become more complicated each year....