2021 Yukon no heat

[czubas]

Picked up my 2021 Yukon with Duramax last Monday after a 5 month wait. Took it home, 9 days later I had no heat from drivers vents, would not defrost windshield after 1 hr running. Took it to dealer, they said coolant was low. Picked it up, did not warm up on the 25 minute drive home, took it back to dealer they replaced the heater core. Picked up today, let it run 45 minutes and no heat from any vents. It’s back at the dealer, no word on the way ahead. I have 450 miles on it.

Any similar experiences? Is this a one off?

 

[Segalldontfly]

Haven’t had a need to use the heat yet but will give it a shot now to be sure … might be a one off. Sorry to hear about your trouble and hope it’s not too cold where you are.

 

[Pro299]

Just started using the heater for the first time the last week or so. Works fine.

I would be a little disappointed too, if my dealer said low coolant or a heater core were the problem. Both seem extremely unlikely. Hot coolant goes to the core and comes back to the engine even on modern hi-tech vehicles. If both hoses on the firewall are hot, then the heater core is also hot. If neither is hot, then a shutoff valve is not being activated as it should. If one is hot and the other not, then you may have a problem with the core. I think I read that the 3.0 has a two-stage process of moving the coolant around in order to speed the warm-up process. I suppose that's a possible participant in the problem, but doesn't seem likely.

My guess would be the core is ok. You didn't say, but I'm assuming your blower is moving vented or AC air through the vents ok and you're just not getting heated air. If that's the case, either a valve is not being commanded to open the heater coolant line, or, more likely the core is hot but the flapper valves controlling air flow through the air box (where the hot and cold air mix) are not opening. That's all done electronically through stepper motors, I think, so the problem could be as simple as a bad connection. Then again, it could be a bad switch, faulty control motor, BCM issue, pinched wire, or some such. Be glad it's under warranty and not your problem. I know, easy for me to say. Leave it to the dealer. I'm sure they'll eventually figure it out.

 

[czubas]

I picked it up after the heater core replacement and still no heat. Dealer has had it for another week. They are replacing the heater core again. Beyond frustrated at this point. I have owner the Vehicle 3 weeks driven it 4 days.

 

[kurtibm]

Maybe ask that your service writer personally inspect the truck after this attempt(?) to ensure the heat is working. That way he/she/it/they cannot just play dumb if is not functioning when you pick up.

 

[ivin74]

I picked it up after the heater core replacement and still no heat. Dealer has had it for another week. They are replacing the heater core again. Beyond frustrated at this point. I have owner the Vehicle 3 weeks driven it 4 days.

Did the dealer fix the heater after all?

 

[Cmoore7]

I’m taking my 21 XL in next week. 7k and no heat unless the car is motion.

 

[bjahoyt]

I’m taking my 21 XL in next week. 7k and no heat unless the car is motion.

Any luck here guys? I've had mine for a year. No issues all last winter. This year, no heat drivers side floor vents only. Every other vent blowing heat just fine. At the dealer now and they just called to say they're replacing the heater core. Not sure how that's gonna fix the problem with every other vent is already blowing heat!?!?

 

[Dustindu4]

So what happened? I would have to guess it was the climate control system and not the heater core if you are getting heat out of at least 1 vent.

 

[Ruralliving]

Newbie here, I have a 2021 Tahoe 3.0 diesel that has no floor heat on the drivers side. I picked it up in October 2021 & noticed the problem on the first Michigan cold day. Had to put a blanket on my lap to keep warm. Took it to the dealership & they said there wasn’t anything wrong with it. Actually, the cup holder/console feels like it’s refrigerated. I’ve been dealing with this for over a year. Tomorrow, February 3rd is going to be single digit high here in Michigan. Surely if I take it back to the dealership and they test drive it, they’d notice no heat? I’ve been hoping there’d be more complaints from other owners that would create some sort of a service bulletin on this issue.

 

[WalleyeMikeIII]

Newbie here, I have a 2021 Tahoe 3.0 diesel that has no floor heat on the drivers side. I picked it up in October 2021 & noticed the problem on the first Michigan cold day. Had to put a blanket on my lap to keep warm. Took it to the dealership & they said there wasn’t anything wrong with it. Actually, the cup holder/console feels like it’s refrigerated. I’ve been dealing with this for over a year. Tomorrow, February 3rd is going to be single digit high here in Michigan. Surely if I take it back to the dealership and they test drive it, they’d notice no heat? I’ve been hoping there’d be more complaints from other owners that would create some sort of a service bulletin on this issue.

If truly Driver Floor only, sounds like a blend door issue for the driver's side HVAC.
Someone else reported freezing drinks in the cupholders while driving and cold...if I find that post, will share it, else search for it.

Edit: Post #97 in the "Whats wrong w/ your ride today" thread.

 

[ivin74]

^X2, you need to take the vehicle to another dealership that can diagnose the vehicle correctly.

 

[Ruralliving]

If truly Driver Floor only, sounds like a blend door issue for the driver's side HVAC.
Someone else reported freezing drinks in the cupholders while driving and cold...if I find that post, will share it, else search for it.

Edit: Post #97 in the "Whats wrong w/ your ride today" thread.

Thank you for finding the thread for me! I've reached out to the individual who posted and asked him to post if he hears any updates on this problem. In the meantime, I'm going to see if I can find a dealership that'll actually listen to my complaint and take it seriously!