No Start/No Crank - Loss Of high Speed GMLAN Communication- keywords abs bcm brake data ecm fpcm inoperative intermittent mil no PIINSIPIT4444 resistor ses short start tccm tcm U0100 U0101 U0102
| Subject: | No Start/No Crank - Loss Of High Speed GMLAN Communication |
| Models: | 2007 Chevrolet Silverado |
| 2007 GMC Sierra |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Some owners may comment of a no crank and/or no start concern, which may be an intermittent or hard fault. If intermittent, when viewing DTC's there will be communication codes for the High Speed GMLAN modules. If the concern is current, the Tech 2 will not be able to communicate with any High Speed GMLAN modules.
Recommendation/Instructions:
This concern could be caused by the High Speed GMLAN circuits (2500 and 2501) shorted to ground or together. Reports have been received of these circuits being pinched between the truck box and frame near the terminating resistor as shown in the picture below, see SI document 1858913 for location. To repair this concern remove the harness from between the box and frame and repair any damaged circuits.
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.
