Caution: To avoid personal injury:

Important: The rear defogger repair kit GM P/N 12346001 contains all of the materials needed to repair the rear window defogger grid lines. You may also use an equivalent repair material.

1. Disconnect the battery feed at the rear window defogger system.
2. Inspect the rear window defogger grid lines (1,3).
3. Use a grease pencil in order to mark the grid line breaks (2) on the outside of the window (4).
4. Complete the following steps in order to prep the grid line area to be repaired:

•	Buff the grid line to about 6.0 mm (0.25 in) beyond each side of the break using fine steel wool.

•	Wipe the area clean using a cloth dampened with alcohol.

Important: 

•	Use a repair decal or tape strips (2) in order to control the width of the repair.

•	If you use a decal, ensure that the die-cut metering slot is the same width as the grid line.




5. Complete one of the following steps:

•	Install a grid line repair decal.

•	Install 2 strips of tape (2).

-	One positioned above the repair area.

-	One positioned below the repair area.

6. Remove the clamp from the container of the grid repair material.
7. Thoroughly mix the hardener and the silver plastic.

If the hardener is crystallized, immerse the packet in hot water until the hardener liquefies.

8. Apply the grid repair material (1) to the repair area using a small plastic paddle (3) or an equivalent.
9. Carefully remove the decal or the tape (2).




Notice: The grid line repair material must be cured with heat. To avoid heat damage to the interior trim, protect the trim near the repair area where heat is to be applied.

10. Using a heat gun, apply heat to the repair area:

•	Hold the heat gun nozzle 25 mm (1 in) from the repair surface.

•	Use a minimum temperature of 149°C (300°F).

•	Apply the heat for 1-2 minutes.

11. Inspect the grid line repair for appearance:

11.1.

If the grid line appears to be discolored, apply a tincture of iodine to the grid line using a pipe cleaner or a fine brush.

11.2.

Allow the iodine to dry for at least 30 seconds.

11.3.

Use a lint free cloth to carefully wipe off any excess iodine.

Important: Protect the trim from heat damage.

12. Allow the repair area to cure undisturbed for at least 24 hours.
13. Test the defogger operation in order to verify that the grid line is repaired.