JanS
Active member
When I turn a temperature control knob to heat the AC button light comes on. It blows hot air fine but is it normal for the button to light up? Why no heat button??? Thanks!
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When I turn a temperature control knob to heat the AC button light comes on. It blows hot air fine but is it normal for the button to light up? Why no heat button??? Thanks!
If you have the HVAC controls set to defrost,The AC runs with it to remove humidity from the passenger compartment.
Try setting your vents to the floor with the temp turned all the way up and see if the AC light go's out,If it don't,pull the codes and lets see whats happening!
Post them ALL , History and Current.
Turn the key to the ON position, but don't start the engine. Clear any present messages by pressing the RESET button. Hold the OPTIONS button down, and press the FUEL button 4 times. This will get you into the CODES section of the DIC. The computer will automatically display all the codes your car has created. It will cycle through each code every 3 seconds. Any code that ends in H is a history code (something that has occurred in the past) but is fine now. Once the computer has finished going through all of it's codes, press RESET to enter Manual Configuration mode. It should start with a module and show "NO CODES" or "# CODES".
When I turn a temperature control knob to heat the AC button light comes on. It blows hot air fine but is it normal for the button to light up? Why no heat button??? Thanks!
. It's infuriating to me, but that is the way GM programmed it.
2nd that ^
Just figured out that the unit is defective. The mode button does nothing. It stays on floor and dash vents. You can't choose another mode. I'll pull it out and send it off to be re-built. Thanks!
So, your problem is more than first reported after all. Testing the whole system and pulling codes are always the best place to start a trouble shooting session.
Vacuum is used to control the vents. I would do a vacuum test from the canister to the unit to see if that is your issue. Very common to have an issue from battery acid on the small plastic line. It will not throw any codes.
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Mr. Sam
Well it turned out to be the HVAC unit was bad. When I pulled it out of the car the bottom was all sticky from what looked like Coke or Pepsi. I wiped that off and sent it out for repair. The repair guy called to tell me that the drink spilled on the circuit boards and shorted them out. That's why the mode button stopped working. The board was beyond repair so he sold me a good reconditioned unit with a lifetime guarantee. He gave me $50.00 for mine because the power supply was still good and sold me the replacement for $250.00 with my core.
Yes it is normal, depending on the MODE you set.When I turn a temperature control knob to heat the AC button light comes on. It blows hot air fine but is it normal for the button to light up? Why no heat button??? Thanks!
Yes it is normal, depending on the MODE you set.
If you do not want a/c set the mode to FLOOR.
Well it turned out to be the HVAC unit was bad. When I pulled it out of the car the bottom was all sticky from what looked like Coke or Pepsi. I wiped that off and sent it out for repair. The repair guy called to tell me that the drink spilled on the circuit boards and shorted them out. That's why the mode button stopped working. The board was beyond repair so he sold me a good reconditioned unit with a lifetime guarantee. He gave me $50.00 for mine because the power supply was still good and sold me the replacement for $250.00 with my core.