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For 1990-2009 cars only

Roof Beacon Switch Left On Causing Battery Draw - keywords dead lamp light low power relay voltage weak

Subject:Roof Beacon Switch Left On Causing Battery Draw

Models:2003-2006 Chevrolet Avalanche, Tahoe, Suburban
2003-2008 Chevrolet Silverado, Silverado Classic
2003-2008 GMC Sierra, Sierra Classic



This PI was superseded to update model years. Please discard PIT3385C.


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

Condition/Concern:

Battery is discharged for no apparent reason.

Recommendation/Instructions:

A vehicle equipped with RPO VYU (Snow Plow Provision Package) or TRW (Provisions For Roof Mounted Lamp) may not have the roof beacon light connected. If the customer were to inadvertently press the roof beacon switch to the on position the roof beacon indicator will illuminate on the switch. If the ignition is turned off and the beacon switch is left on a battery draw (140-180 Ma) will occur. The roof beacon switch indicator will no longer illuminate when the key is turned off however the roof beacon relay is still energized. It's suggested that the roof beacon switch be turned off before turning the ignition off to avoid a battery drain.

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.