GMC climate Control Problems
Read below where Experts have answered a variety of questions pertaining to the GMC climate control and problems it can cause.
Why would the GMC climate control (dual control) on the driver’s side suddenly switch from air conditioning to heating on a 2004 Sierra 1500.The most common cause for this to happen is an issue with the driver’s side temperature actuator. This is an electrical component in the GMC climate control system that controls the hot/cold functions of the heater and the a/c heater box. If it loses its internal setting it can jump from hot to cold on its own or even go to heating when cooling is set. If this is the cause the actuator will need to be replaced. The actuator is located under the dashboard on the bottom of the heater box on the passenger side. The actuator should cost about $200 and replacement will require 0.6 hours of labor.
If a 2005 GMC Envoy is fitted with dual GMC climate control but the driver’s side does not provide heat, will rebooting the system or resetting the actuators fix the problem?A reboot may work. Disconnect the battery and reconnect it. This will cause the actuators to recalibrate when the engine is started. After starting none of the GMC climate control functions should be used for two minutes. If this does not work the actuators should be removed to see if the temperature door shafts can be turned by hand to provide heat on the driver’s side. If this produces results, the actuators will need replacement.
What can cause the climate control to fluctuate from hot to cold on a GMC 2000 Envoy if the air conditioner works fine otherwise?There are a few reasons why this could occur. If the a/c compressor is working okay check the lines running from the compressor to see if one of them is ice cold and if it remains so with the a/c on. If the line warms up and then goes cold again it indicates that there is not enough Freon in the system. This could be caused by a leak in one or more of the a/c components and an a/c leak machine will be required to locate the leak. If the line stays cold, it could mean a defective actuator on the heater box. The actuator controls the heating and cooling operations and a defective one could cause the problem being faced. Another reason for this could be a defective push button a/c / heater control on the dashboard. A reading of the fault codes, if any, will help to pinpoint the problem.
The air conditioner fan on a 2003 Denali fitted with auto GMC climate control will not shut off even with the ignition off and the key out. What is the reason and what can be done to fix it?GMC has issued a recall for fans that will not shut off. This is the reference:
Bulletin No.: 11046
Date: April 07, 2011
Subject: 11046 - Special Coverage Adjustment - Heating, Ventilation, and Air Conditioning Blower Not Fully Functional on All Blower Speeds, Inoperative, or Runs Continuously with the Ignition Off
2003-2006 Chevrolet Avalanche, Suburban, Tahoe
2003-2007 Chevrolet Silverado
2003-2006 GMC Yukon, Yukon XL
2003-2007 GMC Sierra
The dealer should be contacted for free repair. Another reason for this to happen is a defective blower resistor. It is located next to the blower under the right side of the dashboard. Unplug it and check for signs of melting or other damage. If it is damaged, it needs to be replaced.
The GMC climate control is an integral part of a comfortable driving experience and when it is defective the discomfort felt by the driver can affect his or her driving skills. For this reason problems with the climate control should be attended to without delay. Finding the reason for climate control problems can be difficult and time consuming. Answers and insights obtained from Experts will simplify the process and allow for quick and economic repairs to be done.