When I’ve been running my XPS L501X on battery alone (disconnected from the AC adapter) for a half hour or so and then reconnect to the AC adapter, I get a message saying that the AC adapter type cannot be determined.  I’m using the Dell AC adapter that came with the computer (from Dell).  I’ve checked the output from the AC adapter with a voltmeter and it is producing the proper output voltage.  The ID pin in the AC adapter connector tip looks fine.  Connections between the wall outlet and the plug, the power cord and the AC adapter, and the AC adapter to the computer are all tight and complete.  The blue light is solid on at the computer end of the power cord.  I’ve disconnected and unplugged the AC adapter, restarted the computer, turned it off and removed and replaced the battery, all
to no avail.  When I restart, I get the same error message.  I’ve been able to get a normal restart only by letting it sit turned off overnight with the AC adapter unplugged and disconnected from the computer.  It’s happened twice now and I’m afraid the next time it does I won’t be able to get a normal restart.  If that happens, I’ll be totally screwed as I’m traveling and do not have access to any other computer.

I run my laptop connected to the AC adapter most of the time and have not noticed any degradation in the battery life.  The Dell Battery Meter – Battery Health says “Your battery is performing normally.”  I have also verified that I have the latest version of BIOS.

Does anyone have any thoughts or suggestions?