TrailBlazer 4WD L6-4.2L VIN S (2002)
Heated Glass Element: Description and Operation
Rear Window Defogger
REAR WINDOW DEFOGGER SYSTEM COMPONENTS
The rear window defogger system consist of the following components:
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HVAC control module
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Liftgate Module (LGM)
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Rear window defogger grid
REAR WINDOW DEFOGGER OPERATION
Battery positive voltage is supplied through the LGM 2 fuse to the LGM for the rear window defogger system. When you turn the ignition to the ON
position, and the rear window defogger switch is depressed. The HVAC control module illuminates the rear window defogger indicator and sends a
class 2 message to the LGM to enable the rear window defogger system. The LGM enable the rear window defogger system by allowing battery
positive voltage to the rear window defogger.
When you turn ON the ignition and press the rear window defogger switch for the first time, the defogger cycle lasts 10 minutes. Further operation
results in 10 minute defogger cycles.
Adhesive Service Kit Description
The GM Adhesive Caulking Kit P/N 12346392 contains the following items:
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4 different primers
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A tube of urethane adhesive with a nozzle
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4 daubers
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Instructions with warnings
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Use the urethane adhesive caulking kit for replacement of any urethane adhesive-installed window using the Full Cut Method.
You may use an equivalent urethane adhesive system if the system meets GM Specification GM 3651M. Always follow the system manufacturer's
instructions for application, handling, and curing.
Full-Cut Method Description
Use only the full cut method also know as in the field as Full Strip Method when installing windows.
This method includes the following:
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The replacement of a majority of the urethane adhesive bead remove all but approximately 2 mm (3/64 in) of the existing bead of urethane
adhesive from the pinch-weld flange.
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Applying pinch-weld primer to any exposed painted areas on the pinch-weld flange.
No mounds or loose pieces of urethane adhesive should remain on the pinch-weld flange. Do not remove all traces of urethane adhesive.
IMPORTANT:
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If corrosion of the pinch-weld flange is present, or if sheet metal repairs or replacements are required, refinish the pinch-weld flange in order to
present a clean, primer-only surface.
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If paint repairs are required, mask the flange bonding area, prior to applying the color coat, in order to provide a clean, primer-only surface.
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Appropriate materials for these primer applications are typically 2 component catalyzed products. Use materials such as BASF DE15(R), DuPont
2610(R), Sherwin-Williams PSE 4600 and NP70(R) and Martin-Semour 5120, 5130(R), PPG DP90LF SPIES/ HECKER 3688/8590 - 3688/5150
- 4070/5090 STANDOX 11158/13320 - 14653/14980 products are approved for this application. Follow the manufacturer's directions for the mix,
the application, and the drying times.
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After repairing the opening as indicated, shake the pinch-weld primer black #3 well. Using a new dauber, apply the primer to the primed surface of
the flange in the bonding area. Allow the primer to dry for 10 minutes.
Stationary Window Description
Most stationary windows, specifically windshields, are retained to the body with urethane adhesive which adheres the window to the body, increasing
structural integrity. The reinstallation of the windows with urethane adhesive requires complete replacement of the urethane adhesive bead, and is know
as the Full Cut Method.
Compass Calibration and Variance Procedure
COMPASS CALIBRATION
Before calibrating the compass, drive the vehicle to an area that is magnetically clean or free of large metallic objects. Verify there are no magnetized
objects on the inside or outside of the vehicle close to the mirror.
1. Start the engine.
2. Press and hold the switch for the compass, which may be depicted as COMP, COMPASS, or On/Off (W/UE1) depending on the type of mirror on
the vehicle, until the letter "C" or "CAL" is displayed.
3. Drive the vehicle in circles at a speed of less than 8 km/h (5 mph) until the "C" or "CAL" is replaced by a proper vehicle heading. The calibration
procedure is now complete.
COMPASS MAGNETIC VARIATION ADJUSTMENT
Magnetic variation adjustments are required when the compass displays a constant error in heading. Variation is the difference between magnetic
