LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 2006 >> Sierra 1500 HD, 4WD >> Repair and Diagnosis >> External Pages >> Different car >> Section 992 (Fixed & MOVEABLE Window Systems) >> Diagnostic Information and Procedures >> Rear Window Defogger Malfunction >> Circuit/System Verification

Circuit/System Verification

WARNING: This page is about a different car, the 2008 GMC Sierra, 2008 GMC Cab & Chassis Sierra, 2008 Chevrolet Silverado, and 2008 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition ON, observe the scan tool Rear Defrost State parameter while pressing the rear window defogger switch. The parameter should change between On and Off.
    • If the parameter does not change between the commanded states, replace the HVAC module.
  2. Observe the operation of the rear window defogger indicator while pressing the rear window defogger switch. The indicator should turn ON or OFF each time the rear window defogger switch is pressed.
    • If the indicator does not turn ON or OFF with each switch press, replace the HVAC module.
  3. Command the rear window defogger ON and OFF with a scan tool. The rear window defogger should turn ON and OFF when changing between the commanded states.
scientia non olet · About LEMON Manuals