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Engine Cranks With The Ignition Switch In The Run Position - keywords 4.2 4.2l 5.3 5.3l 6.0 6.0l connection connector deterrent fuse intermittent key lh6 ll8 ls2 mode power powermode rotate start

Subject:Engine Cranks With The Ignition Switch In The Run Position

Models:2005-2007 Buick Rainier
2005-2009 Chevrolet Trailblazer Models
2005-2009 GMC Envoy Models
2005-2009 Saab 97x



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

Condition/Concern:

Some customers may comment that the vehicle cranks when the key is rotated to the RUN position. This may be due to a loss of voltage on circuit 4 between the Ignition Switch and the BCM (Body Control Module).

Recommendation/Instructions:

Buick, Chevrolet and GMC Reference Document ID 1764016 and Saab 97x Reference Document ID 1767232 for electrical schematics.

- Verify voltage on the TBC ACC fuse number 31 in the ACCY and RUN position. This fuse is located in the Rear Fuse Block. If voltage is missing in these two ignition switch positions, isolate the open in circuit 4.

Note: Since this is due to a loss of voltage, it will be necessary to inspect for poor terminal connections prior to replacing any components.

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.