Subject: | Intermittent No Crank |
Models: | 2007 Cadillac Escalade, ESV, EXT |
2007 Chevrolet Avalanche, Silverado, Suburban, Tahoe |
2007 GMC Sierra, Yukon, Yukon XL, Yukon Denali, Yukon Denali XL |
This PI was superseded to update Recommendation/Instructions and to add illustrations. Please discard PIT4319A.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Some customers may comment that they experience a no crank condition on full size pickups and utilities built on and after January 2, 2007 through March 16, 2007 . A new designed ignition switch was introduced that may not be fully compatible with the ignition lock cylinder case. This may result in a customer believing the truck will not crank due to the effort required for ignition key rotation.
To repair this concern remove the ignition lock cylinder case and modify the gear detent, as shown below
Remove the internal gear detent from ignition lock cylinder case as shown below. The gear detent is held in place by a plastic cage that can be removed by inserting a pick in two small holes that are located on the left and right sides of ignition lock cylinder case.
Measure the main starter detent tab with a dial indicator or equivalent. (See Photo below)
If the gear measurement is .177 " inches or 4.5 mm, the starter detent tab will have to be modified to .130" inches or 3.3 mm. Remove material from the left side portion of the starter detent tab on the gear. See photo below.
Finished product (See Photo Below)
Re-assemble lock cylinder.
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.