The most common problem with the heating control on a Chevy Silverado is the dual climate control blowing hot air to one side of the cab, while blowing cold air to the other side. This problem occurs when using either heat or air conditioning. Temperature adjustments only prove effective to the side with appropriate function. Another problem that can occur is the air conditioning fully turning on when heat is chosen, and heat fully turning on with air conditioning.
Common causes for the heat control issues include blown fuses, a lack in battery contact, control panel relay issues, battery reset and the failing of HVAC air delivery or temperature mode door actuators, which can result in incorrect temperatures and air delivery. Most issues involving HVAC actuators leave a fault code history. Fault codes are stored in the HVAC panels of every Chevy Silverado and are able to be read and diagnosed with equipment available at repair shops, auto supply stores and dealerships.
HVAC blower motor resistors and harnesses have been catalogued as causing problems with dual temperature control in the 2003-2007 Silverado Classic models, and were voluntarily recalled by GMC. Recall repairs are only made, however, if the vehicle shows signs of the temperature control issue.