2009 Enclave heater fan cutting out & warm air issue

[BuickAndTired]

Hey there! I've got a 2009 Enclave, and I've been running into a really strange issue. The heater fan and climate control just decide to shut off on their own sometimes, and then, out of the blue, they'll pop back on. When it's actually working, the air is warm, but not hot enough—you know? I mean, even cranking it all the way up to 30°C doesn't help much.

Coolant levels are good, so that's not the problem. Oh, and just to throw this into the mix, I had to replace a dead battery about two weeks ago—no clue if that has anything to do with it, though.

Has anyone else experienced anything like this? I'd really appreciate any tips or ideas you might have!

 

[SmoothSailor]

It sounds like your Enclave's HVAC is giving you a bit of trouble. That can be super frustrating. Usually, it's something like a faulty blend door actuator, a finicky HVAC control module, or maybe even a dodgy ambient temp sensor. Since you just changed the battery, it might not hurt to check for any loose or corroded connections, too. Have you tried resetting the system by pulling the fuse for a minute? What have you looked into so far?

 

[Knight1]

What could cause both the heater fan and temp control to cut in and out like that maybe a flaky HVAC control module or a voltage issue tied to the recent battery swap?