Surface Slim pen 2 cannot charge when battery completey drained and not connected to surface

Try this in order:

1. Wake the pen with a brief charge Surface Slim Pen must be charged before use, and for first use it only needs to charge for a second to wake up. Place each pen in the charging area of the keyboard again and check the LED.
2. Check the LED behavior
   • White fading in and out = docked and charging
   • Amber fading in and out = low battery
   • Amber and white flashing = charging accessory needs an update
   • No LED = continue with the steps below
3. Make sure the Surface is powered correctly The Surface device must be plugged into power and turned on. If the device is off, in hibernate, or has low battery, it may not charge the pen.
4. Reconnect the keyboard charging accessory For a Surface Pro Keyboard charging tray:
   1. Detach the keyboard.
   2. Go to Start > Power > Shut down.
   3. After shutdown, press and hold the power button for 20 seconds. If the logo appears, keep holding until it appears again.
   4. Reattach the keyboard.
   5. Press Caps and Fn to confirm the keyboard is receiving power.
   6. Put the pen back in the storage tray.
5. Check for accessory and firmware updates If the pen still does not charge in the keyboard tray:
   1. Connect the charging accessory to the Surface.
   2. Place the pen in the storage area.
   3. Open the Surface app.
   4. Expand Help & support.
   5. Select Check for updates to open Windows Update and install available updates.
   6. Restart if required.
   7. Check the pen LED again.
6. Use the Surface app to verify status In the Surface app, connected Surface accessories appear at the bottom. If the pen can take any charge, its battery level can be checked there.
7. Test whether the problem is the pen or the keyboard charger If possible, try another compatible charging method such as the Surface Slim Pen Charger. According to Microsoft guidance:
   • If the pen does not charge there either, the pen should be replaced.
   • If the pen does charge there, the original charging accessory should be serviced or replaced.
8. If there is still no LED and no charging Microsoft guidance is to request service/replacement for the failed part:
   • If neither pen charges in another charger, replace/service the pen.
   • If the pens charge elsewhere, service the keyboard charging accessory.

Since both pens fail in the keyboard tray, the strongest supported next step is to verify the keyboard charging path by reconnecting it, confirming Caps/Fn respond, and installing updates through the Surface app. If that does not restore charging, service is the documented next action.

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