Interior Cabin Temperature Regulation

[nova72]

H, I have a new to me 2015 Tahoe with 72K miles. I'm having an issue with regulation/control of the interior cabin temperature. This occurs when heating in cold weather, 30-50 degree ambient outside.

I can set the temperature control at 70 and get warm air from the dash and floor vents, but as the interior warms, the system continues to blow hot air. I then end up dialing back the temperature control a few degrees at a time to cool the air, but the system does not change until I get the temperature control down to 64-65 at which point it starts to blow cold air.

It seems like the system does not moderate the air temperature supplied as the interior warms.

I assume the blend doors are working as the system will change the air temperature supplied from hot to cold and back, just not in between.

There are no codes set in the HVAC module. A check of the interior temperature sensors with a scan tool shows them to be reading correct.

I normally use bi-level for air distribution when heating, but I don't think this would effect anything.

Any suggestions on how to diagnose or fix this?

 

[Joseph Garcia]

I cannot personally assist you with your issue, but other members of this Forum much more knowledgeable than me in this area will chime in.

 

[jets]

H, I have a new to me 2015 Tahoe with 72K miles. I'm having an issue with regulation/control of the interior cabin temperature. This occurs when heating in cold weather, 30-50 degree ambient outside.

I can set the temperature control at 70 and get warm air from the dash and floor vents, but as the interior warms, the system continues to blow hot air. I then end up dialing back the temperature control a few degrees at a time to cool the air, but the system does not change until I get the temperature control down to 64-65 at which point it starts to blow cold air.

It seems like the system does not moderate the air temperature supplied as the interior warms.

I assume the blend doors are working as the system will change the air temperature supplied from hot to cold and back, just not in between.

There are no codes set in the HVAC module. A check of the interior temperature sensors with a scan tool shows them to be reading correct.

I normally use bi-level for air distribution when heating, but I don't think this would effect anything.

Any suggestions on how to diagnose or fix this?

Perhaps the temp sensor(s) are not working correctly?

 

[Oh Kee Pah]

@nova72 - any updates?

I too have this same issue with running the heat in colder temperatures in my 2015 Tahoe LTZ.
It actually gets really hot sometimes; we have opened the windows to let the cold air in just to bring the cabin temp down and somewhat comfortable again.

 

[nova72]

@nova72 - any updates?

I too have this same issue with running the heat in colder temperatures in my 2015 Tahoe LTZ.
It actually gets really hot sometimes; we have opened the windows to let the cold air in just to bring the cabin temp down and somewhat comfortable again.

Have not done anything else with this issue. Thinking about replacing the HVAC control module and see if that helps.