GM Service Manual Online
For 1990-2009 cars only

RPO 9L4 12 Volt Auxiliary Wiring - keywords wire fuse harness glove box connector power supply terminal

Subject:RPO 9L4 12 Volt Auxiliary Wiring

Models:2003-2007 Chevrolet Silverado Classic
2003-2007 GMC Sierra Classic
2003-2006 Chevrolet Surburban and Tahoe
2003-2006 Yukon and Yukon XL



This PI is being updated to add Tahoe and Yukon Models. Please discard PIT4026.


The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Some questions regarding a wiring harness, with blunt end wires, located behind the glove box have been received. If the vehicle is equipped with RPO 9L4 this is an auxiliary 12 volt power supply. A description and wiring schematic can be found in SI under Document ID numbers 878970 and 878909.

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.