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Makes 🢒 GMC_Truck 🢒 2007 🢒 Sierra Denali 🢒 Bulletins 🢒 Low Speed Lan No Sound From Radio Backlighting Inop - keywords battery BCM blown body back communication dead draw dimming front fuse inoperative is islps IPC lamp led left lighting low lo lps on rdo

Low Speed Lan No Sound From Radio Backlighting Inop - keywords battery BCM blown body back communication dead draw dimming front fuse inoperative is islps IPC lamp led left lighting low lo lps on rdo

Subject:Low Speed Lan, No Sound From Radio, Backlighting Inop

Models:2007-2008 Chevrolet Silverado
2007-2008 GMC Sierra
Excluding Denali Models


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

Condition/Concern:

Some owners may comment of one or more of the following concerns:

  1. IP back lighting inoperative
  2. Radio sound inoperative or cutting off
  3. IPC warning indicators coming on
  4. No Crank
  5. Radio Inoperative

When checking for DTCs there may be several low speed lan communication codes. Also the Radio and/or ISLPS fuses may be blown. These concerns could be caused by an IP harness shorted behind the center ip hvac vent, as shown below. A trim screw used to attach part of the hvac ducting may cut into the IP harness and short out various wires. Owner complaints may vary depending on which wires are shorted.


Object Number: 2086366 Size: SH
  1. Trim Screw
  2. IP harness
  3. X212 connector

Recommendation/Instructions:

Repair any damaged wiring and reposition the IP harness away from the trim screw to prevent any chaffing.

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.