For 1990-2009 cars

A single application of the Air Conditioning Deodorizer, GM P/N 12377951, removes musty odors from the air conditioning system.

1. Turn the ignition switch to the LOCK position.
2. Set the parking brake.
3. Make sure that the cowl vent grill is clear.
4. Place an auxiliary fan in front of the vehicle.
5. Set the A/C switch to OFF.
6. Set the mode to VENT.
7. Set the fresh/recirc to FRESH.
8. Set the temperature to full HOT.
9. Start the engine.
10. Set the blower speed to HI for 10 minutes.
11. Shake well the contents of the Air Conditioning Deodorizer, GM P/N 12377951.
12. Insert the extension tube into the can nozzle.
13. Pull the instrument panel compartment out while pushing the right and left stoppers inward.
14. Disconnect the blower motor resistor.
15. Remove 1 screw and the the motor blower resistor from the blower case.
16. Wear safety goggles and latex gloves.
17. Cover the carpet area underneath the blower case and the evaporator case with a shop rag in order to collect any deodorizer liquid that may spill out.
18. Insert the extension tube into the blower resistor hole past the mark on the tube.

With the blower still on HI, spray the contents of the air conditioning deodorizer over a 5 minute period with short bursts while varying the direction of the tube.

19. Turn the blower speed to OFF.
20. Turn the ignition switch to LOCK.
21. Let the vehicle sit for 5 minutes.
22. Start the engine.
23. Reinstall the blower resistor to the blower case. Secure the blower resistor with one screw and connect the electrical connector.
24. Close the instrument panel compartment.
25. Set the blower speed to HI for 20 minutes.
26. Turn the ignition switch to LOCK.