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Flash Fogging Occurs When DEFOG is Selected in Cold, Moist Conditions (Repair Heater and A/C Control Assembly)

Subject:"Flash" Fogging Occurs When DEFOG Is Selected In Cold, Moist Conditions (Replace Heater & A/C Control Assembly)

Models:2000-2002 Pontiac Bonneville Built Prior to VIN Breakpoint 24130170
With RPO C67



Condition

Some customers may comment that after selecting the DEFOG mode on the Standard (Manual) Climate Control System, the windows will suddenly fog up. Depending on where the temperature selector is placed and the outside ambient conditions (temperature and humidity), there can be as much as a 10°C (50°F) difference between the defroster and heater duct discharge air temperature.

Cause

This condition may be due to air that is normally routed through the heater core being allowed to bypass the heater core. Most of the air that is allowed to bypass the heater core, under these circumstances, is routed upward to the defroster vents.

Correction

Modifications have been made to the Heater and Air Conditioning Control Assembly. Replace the HTR & A/C Control Assembly. Refer to Control Assembly Replacement in the HVAC System-Manual sub-section of the Service Manual.

Parts Information

Part Number

Description

25732792

Control Asm, HTR & A/C

Parts are currently available from GMSPO.

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation

Description

Labor Time

D0362

Control Assembly-Replace

Use published labor operation time