[ChevMali99]

Hello - As the title alludes to, my 2009 Traverse puts out very anemic heat in the cabin.

I scoured the web for videos on what could be the problem and a few potential culprits were cited. But first, let me go into what is actually happening.

As soon as I turn the ignition on, the radiator fans are blowing. Though I find that strange, several GM sites say it is normal operation, eventhough having the fan constantly on, in the winter no less, keeps the operating temperature way below optimal operating conditions for a longer period of time. In other words, it takes longer for the car to warm up and give proper cabin heat.

I checked the dexcool levels in the reservoir and the radiator, both were topped full. I moved on to replacing the temp sensor and the problem remained - It's no fun to drive in a less than warm cabin.

Moved on to the HVAC Blend Door Actuator, as many videos suggested but before committing to this solution, I took a look at the actuator in the car and saw it rotate from position to position with zero problems. Remember, there is actual temperature change; it's just not hot enough - the cabin is barely warm. So I ruled the actuator problem out.

There have been episodes where, after sitting in slow traffic, the temperature in the cabin spikes up to suffocating levels! Leading me to believe, maybe there's a blockage somewhere. But when I check the reservoir there is no murky dexcool - Oh! Yes, I did perform a radiator flush, replaced the water pump, and the thermostat. YET the hose connecting to the driver side cabin is never piping hot.

So I am back to the radiator fans but this time checking the relays. I mean, why is this thing on as soon as the car is turned on? I start swapping fan relays 1, 2, 3 – no change. Basically 1 & 2 are exactly that fan 1 & fan 2. Relay 3 is turbo fan speed. All seems to be on point with the relays, except when they remain un-plugged. When relays 1 & 3 are unplugged, the fans go on turbo mode. But when relay 2 is unplugged the fans do not go on automatically with the car and actually allows the temperature, both operating & cabin temps to go up. And yes, the temperature remains steady in the middle with the fans alternating between off and turbo.

I know, by driving with relay 2 unplugged, I’m tempting fate and asking for trouble, but that is the closest thing to a solution which allows the fans to remain off until needed, let the temperature go up to middle and keep the cabin toasty. Still, what could be the problem? A bad thermostat stuck open or bad relays keeping the fans on?


.