LaCrosse V6-3.6L (2007)
Control Assembly: All Technical Service Bulletins
A/C - Rear Defogger/A/C Inop On Start Up
Bulletin No.: 07-01-39-001
Date: January 12, 2007
TECHNICAL
Subject:
HVAC/Rear Window Defogger (Defroster) Inoperative/HVAC Indicator Lights Flashing During Remote Start (Reprogram HVAC Control Head)
Models:
2007 Buick Allure (Canada Only), LaCrosse
2007 Pontiac Grand Prix
with Automatic Climate Control (CJ2) and Remote Start (AP3)
Attention:
The chart shown contains the affected date ranges of vehicles which may have the above condition. In ALL CASES, you must verify the part number
of the HVAC Control Head with the Diagnostic Scan Tool BEFORE attempting reprogramming. Only the control head part numbers mentioned in
this bulletin are capable of being reprogrammed. Attempting reprogramming on any other HVAC control head will render it permanently inoperative.
Condition
Some customers may comment that during remote starting, the HVAC system and rear window defogger are inoperative. The HVAC indicator lights will
also flash while the vehicle is in remote start mode and the key has not yet been inserted into the ignition.
After the ignition key is turned to RUN, the HVAC system/rear window defogger will operate normally and the HVAC indicator lights will stop flashing.
Cause
During the 2007 model year, a physical change was made to the processor in the HVAC control head. The new processor was not programmed to
acknowledge remote start events.
Correction
A limited number of vehicles built within the date ranges shown above may have had the HVAC control head already reprogrammed. Before attempting
reprogramming, verify the customer concern. You should start the vehicle with the remote start function and check that the HVAC indicator lights flash
on and off.
Reprogram the part number shown HVAC control heads.
If the HVAC control head part number shown on the Diagnostic Scan Tool component identification for the vehicle is NOT one of the P/Ns shown
above in the table, DO NOT attempt to reprogram the control head. Attempting reprogramming on any other HVAC control head PIN will render it
