No Crank / No Start At Times - keywords code communication DTC high lan speed U0100 U0101 U0102 U0140 U2100 U0073
| Subject: | No Crank / No Start At Times |
| Models: | 2007-2008 Cadillac Escalade, ESV, EXT |
| 2007-2008 Chevrolet Avalanche, Silverado, Suburban, Tahoe |
| 2007-2008 GMC Sierra, Yukon, Yukon Denali, Yukon XL, Yukon Denali XL |
| 2008 Hummer H2 |
This PI was superseded to update models and model years. Please discard PIT3993B.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Some customers may experience a "No Crank" condition at times. During diagnosis, there may be no communication with any module on the GM High Speed Lan or multiple GM High Speed Lan "loss of communication" codes.
Recommendation/Instructions:
Some reports from the field have found the GM High Speed Lan terminating resistor shorting out and pulling down the GM High Speed Lan data line. If you experience this concern, remove the terminating resistor and swap it with a known good vehicle and re-test the vehicle, If the concern goes away, replace the terminating resistor.
When replacing the terminating resistor, please use GM part number: 88988999
Note: The resistance of the terminating resistor should be approximately 121 ohms.
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.
