| Subject: | Start Stall DTC P1629 After Theft Deterrent Module Replacement |
| Models: | 2006-2008 Buick Lucerne |
| 2006-2008 Chevrolet Impala |
| 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 |
This PI was superseded to update models and model years. Please discard PIC3879.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
If Theft Deterrent Module (TDM) is replaced without following the proper published service procedures, the Manufactures Enable Counter (MEC) in the TDM will not be zero. If the MEC is not zero, the vehicle may start and stall with a DTC P1629 set in Engine
Control Module (ECM).
Recommendation/Instructions:
The MEC status can be read using the Tech 2. The MEC is found under Module ID for the Theft Deterrent Module. If the Manufactures Enable Counter display is blank then the TDM has been programmed. If the Manufactures Enable Counter reads a value other than
zero, then the TDM needs to be programmed. Refer to eSI Document ID # 1704081 for TDM programming procedure.
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.
