Sierra 1500 2WD V6-4.3L (2008)
GM Engineering is seeing an increase in HVAC control head and actuator warranty where the component is fully functional when received. The root
cause of the failure is intermittent wiring connections at the right hand BEC. Specifically, poor terminal tension of the 5V reference or Low Reference
terminals in the X4 connector. Refer to the table.
After the fault is removed. the actuators recover once commanded.
Correction
DO NOT REPLACE THE CONTROL HEAD.
Use the following information to diagnose this condition:
