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Engine Battery Light Remains On For 30 Seconds After A Cold Start - keywords charge dash die diesel draw generator gage gauge indicator IPC LB7 LBZ low LLY volt voltage

Subject:Engine Battery Light Remains On For 30 Seconds After A Cold Start

Models:2006-2007 Chevrolet Express
2001-2007 Chevrolet Silverado Classic
2006-2007 GMC Savana
2001-2007 GMC Sierra Classic
With 6.6L Diesel



This PI was superseded to update Recommendation/Instructions. Please discard PIT3314B.


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

Condition/Concern:

Battery or charge indicator light remains on for up to 30 seconds after a cold start and engine running. This concern may be accompanied by a lower than normal volt gauge reading.

Recommendation/Instructions:

No repairs should be made for this concern. This is a normal operating characteristic of these vehicles equipped with the diesel engine. When starting a cold engine, glow plug cycle time can last 18 seconds with an after glow time of 30 seconds depending on engine temperature. After glow time, of the glow plugs, is not indicated by the dash telltale. Average glow plug amperage draw is 130 amps. The intake air heater can use 45 amps. Due to these high current draws the battery light may remain on until the amperage draw is reduced.

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.