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No Crank No Start Security Light On Or Off - keywords B2960 B3031 P1626 P1629 theft lamp indicator

Subject:No Crank No Start Security Light On Or Off

Models:2004-2007 Buick Rainier
2002-2007 Chevrolet Trailblazer, Trailblazer EXT
2002-2007 GMC Envoy, Envoy XL, Envoy XUV
2002-2004 Oldsmobile Bravada
2005-2007 Saab 97x



This PI has been updated to include 2007 model year vehicles. Please discard PIT3550.


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

Condition/Concern:

Intermittent no crank no start. Security light may be on or off

Recommendation/Instructions:

On the 4.2L LL8 engine, theft deterrent will disable crank. If a no crank no start concern is encountered, inspect for a DTC(s) in the PCM and BCM to make sure the concern is not theft related. Also in the PCM data list 3, it will allow the VTD fuel disable, crank request signal and starter relay command to be viewed to aid in diagnosis.

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.