T-150 Transfer Case Phantom Shift - keywords 4HI 4WD HI4 light NP1 position shift switch unwanted
| Subject: | T-150 Transfer Case Phantom Shift |
| Models: | 2004-2007 Chevrolet Colorado |
| 2004-2007 GMC Canyon |
| Equipped with 4WD |
This PI was superseded to remove module replacement. Please discard PIP3558J.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Unrequested transfer case mode shift. Condition is likely intermittent.
Recommendation/Instructions:
Inspect for water intrusion under the carpet in the area of the Transfer Case Control Module. If water intrusion is found, check for the source. Two known concerns have been with the shift cable grommet just below the brake pedal and also the grommet for the hood release cable. These grommets may be the source of water intrusion if no others are found.
Inspect the electrical connectors at the tccm make sure that they are fully seated. Listen for an audible 'click' as the connectors are reinserted.
If no water intrusion is found and the connections at the tccm have been verified attempt no further repairs at this time as this condition is currently under an engineering investigation.
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.
