Dell Vostro 1540 (Mid 2011) - Manual (Page 78)

Battery Status Lights
If the computer is connected to an electrical outlet, the battery light operates as
follows:
• Alternately blinking amber light and white light — An unauthenticated or
unsupported non-Dell AC adapter is attached to your laptop.
• Alternately blinking amber light with steady white light — Temporary battery
failure with AC adapter present.
• Constantly blinking amber light — Fatal battery failure with AC adapter
present.
• Light off — Battery in full charge mode with AC adapter present.
• White light on — Battery in charge mode with AC adapter present.
Device Status Lights
Turns on when you turn on the computer and blinks when the computer is in a
power management mode.
Turns on when the computer reads or writes data.
Turns on steadily or blinks to indicate battery charge status.
Turns on when wireless networking is enabled.
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