Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
You most likely have an internal shorted circuit in the HVAC control module.This should help you ,the module has to be programmed after replacement.
Heater and Air Conditioning Control Replacement
Important: The key should be in the off position when connecting the electrical connectors to ensure proper calibration.
Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Tighten Tighten the screws to 1.8 N·m (16 lb in).
Important: Do not adjust any controls on the HVAC control module while the HVAC control module is calibrating. If interrupted improper HVAC performance will result.