Document ID: 2389114
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2008 Chevrolet Silverado - 4WD | Sierra, Silverado VIN C/K Service Manual | Document ID: 2389114
#PIT4846B: Locations Of High Speed GMLAN Wiring Concerns - keywords cycle gage gauge hard hi lamp LAN lock light MIL off shift short start - (Jan 27, 2010)
Locations Of High Speed GMLAN Wiring Concerns
2007-2010 Cadillac Escalade Models 2007-2010 Chevrolet Avalanche, Silverado, Suburban, Tahoe
2007-2010 GMC Sierra, Yukon, Yukon XL, Yukon Denali, Yukon Denali XL
This PI was superseded to update model years. Please discard PIT4846A.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Some owners may comment on various vehicle issues ranging from: IPC indicators on, gages going inoperative, no crank, harsh transmission shifting, no transmission shifting, door locks cycling, etc. When checking for DTCs there will be loss of communication codes for the High Speed GMLAN modules example: u0100, u0101, u0102, u0106, u0109, u0117, u0121, u0122, u0132, u0137, u0140, and/or u0073.
These issues may be intermittent making it difficult to diagnose. Below is a list of common areas where the High Speed GMLAN wiring may have been shorted, chaffed, pinched, terminals backed out, or poor pin fit. These areas have been identified by the field and may not apply to every vehicle depending on the year, make, model and vehicle options.
Adjustable Pedal Motor- As the brake pedal is applied the DLC wiring harness may rub on the adjustable pedal motor and short out, shown below. One hint is the concern will normally occur when the brake pedal is being applied.
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