Dell Precision M2800 Owner's Manual page 71

Alternately An unauthenticated or unsupported non-Dell AC adapter is attached to your
blinking amber laptop.
light and white
light
Alternately Temporary battery failure with AC adapter present.
blinking amber
light with
steady white
light
Constantly Fatal battery failure with AC adapter present.
blinking amber
light
Light off Battery in full charge mode with AC adapter present.
White light on Battery in charge mode with AC adapter present.
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