Dell Latitude 12 Rugged Extreme 7214 Owner's Manual page 86

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