GM Service Manual Online
For 1990-2009 cars only

Replacement HVAC Control Heads Must Be Programmed - keywords a/c ac air CJ2 CJ3 conditioning door DTC defrost erratic heat heater high inoperative low mode operation rear

Subject:Replacement HVAC Control Heads Must Be Programmed

Models:2007-2008 Cadillac Escalade, ESV, EXT
2007-2008 Chevrolet Avalanche, Silverado, Suburban, Tahoe
2007-2008 GMC Sierra, Yukon, Yukon Denali, Yukon XL, Yukon Denali XL
with RPO CJ2 or CJ3



This PI is being superseded to update models and model years. Please discard PIT3906A.


The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Starting with the all new 2007 full size utilities and pickups, all 2007-2008 full size trucks (listed above) with a replacement HVAC control head must be programmed. When a replacement control head is installed it may appear to be operational, but if not programmed, some functionality will be lost.

Recommendation/Instructions:

SPS program any replacement HVAC control head using TIS2000.

Note: This PI doesn't apply to the 2007 Chevrolet Silverado Classic or the 2007 GMC Sierra Classic.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.