Subject: | ISLPS Fuse Blown, Courtesy or Sunshade Lamps Inop, Battery Draw |
Models: | 2007 Cadillac Escalade, EXT, ESV |
2007 Chevrolet Avalanche, Silverado, Suburban, Tahoe |
2007 GMC Sierra, Yukon, Yukon Denali, Yukon XL, Yukon Denali XL |
This PI is being updated to add models and additional symptoms. Please discard PIT4050A.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Some customers may comment the courtesy/reading or sunshade lamps are inoperative and the ISLPS fuse is blown. The ISLPS fuse is a power feed to the BCM and it uses the power from this fuse to feed some of its outputs. One of the outputs is the inadvertent power supply to the courtesy/reading/sunshade lamps on circuit 6815 orange. If this circuit (6815) shorts to ground the ISLPS fuse will blow.
To correct this concern, repair the short and reroute harness so it does not reoccur. In some cases, if circuit 6815 is chaffing/intermittently/or partially shorted to ground, in the areas described above, it may not blow the ISLPS fuse but intermittently wake up the BCM and cause a battery draw.
Reports of this circuit shorting at the overhead DVD screen or at the sunshades have been received.
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.