Recovering The Operating System; Flea Power Release - Dell P121G Service Manual

Table 20. LED codes (continued)
Diagnostic light codes
3,1
3,2
3,3
3,4
3,5
3,6
3,7
Camera status light: Indicates whether the camera is in use.
● Solid white — Camera is in use.
● Off — Camera is not in use.
Caps Lock status light: Indicates whether Caps Lock is enabled or disabled.
● Solid white — Caps Lock enabled.
● Off — Caps Lock disabled.

Recovering the operating system

When your computer is unable to boot to the operating system even after repeated attempts, it automatically starts Dell
SupportAssist OS Recovery.
Dell SupportAssist OS Recovery is a standalone tool that is preinstalled in all Dell computers installed with Windows 10 operating
system. It consists of tools to diagnose and troubleshoot issues that may occur before your computer boots to the operating
system. It enables you to diagnose hardware issues, repair your computer, back up your files, or restore your computer to its
factory state.
You can also download it from the Dell Support website to troubleshoot and fix your computer when it fails to boot into their
primary operating system due to software or hardware failures.
For more information about the Dell SupportAssist OS Recovery, see Dell SupportAssist OS Recovery User's Guide at
www.dell.com/support.

Flea power release

About this task
Flea power is the residual static electricity that remains on the computer even after it has been powered off and the battery has
been disconnected from the system board. The following procedure provides the instructions on how to release the flea power:
Steps
1. Turn off your computer.
2. Remove the base cover.
NOTE: The battery must be disconnected from the system board, see Step 2 in
3. Press and hold the power button for 15 seconds to drain the flea power.
4. Install the base cover.
5. Turn on your computer.
78 Troubleshooting
Problem description
Coin-cell battery failure
PCI, video card/chip failure
Recovery image not found
Recovery image found but invalid
Power-rail failure
System BIOS Flash incomplete
Management Engine (ME) error
Removing the battery.