Rear Window Defogger System Components
The rear window defogger system consists of the following components:
Rear Window Defogger Operation
The rear defog control system utilizes a single zone backlight design, driven with a single relay configuration. Additionally, up to two outside rear view mirrors can be heated if required. A switch for the customer to control the system is provided within the HVAC control head. Also included in the HVAC control head is an indicator to inform the customer with the current state of the system. The system is only operational when engine is running or during remote start.
Pressing the heated rear window switch on the HVAC control face plate causes the HVAC control head to send a serial data message to the HVAC control module requesting rear window defog operation. The HVAC control module upon receipt of the serial data message will provide voltage to the coil side of the rear window defogger relay, this will energize the relay causing the relay switch contacts to close allowing B+ voltage to flow through the rear defogger grid control circuit to the rear defogger grid.
When the rear heated window switch is pressed and the engine is running, the rear defog control system will remain active for 10 minutes.
After the initial cycle has lapsed, pressing the switch again will continue rear window defogger operation, but the cycle will only last 5 minutes. The rear defog control system will function continuously if the vehicle speed is greater than 70 kilometers per hour (45 mph).
Stationary Window Description
Most stationary windows, specifically windshields, are retained to the body with urethane adhesive which adheres the window to the body.
This increases structural integrity. The reinstallation of windows with urethane adhesive requires complete replacement of the urethane adhesive bead: The extended method (also known as long method, full strip or full cut) is the only recommended procedure for General Motors Vehicle.
Special Tools and Equipment
Child Seat Restraint System
Warning: A child in a rear-facing child restraint can be seriously
injured if the right-front passengers air bag inflates. This is because the
back of a rear-facing child restraint would be very close to the inflating air
bag. NEVER use a rear-facing child restraint in this vehicle. If a
forwa ...
Removal Procedure
Warning: Refer to Approved Equipment for Collision Repair Warning in the
Preface section.
Warning: Refer to Collision Sectioning Warning in the Preface section.
Warning: Refer to Glass and Sheet Metal Handling Warning in the Preface section.
Disable the SIR System. Refer to SIR Dis ...
Halogen Bulb Warning
Warning: Halogen bulbs contain gas under pressure. Handling a bulb
improperly could cause it to shatter into flying glass fragments. To
help avoid personal injury:
Turn off the lamp switch and allow the bulb to cool before changing
the bulb.
Leave the lamp switch OFF until the bulb chang ...