Enter Service Mode - Dell Latitude 5520 Service Manual

Standby power
Dell products with standby power must be unplugged before you open the case. Systems that incorporate standby power are
essentially powered while turned off. The internal power enables the system to be remotely turned on (wake on LAN) and
suspended into a sleep mode and has other advanced power management features.
Unplugging, pressing and holding the power button for 20 seconds should discharge residual power in the system board.
Remove the battery from notebooks.
Bonding
Bonding is a method for connecting two or more grounding conductors to the same electrical potential. This is done through
the use of a field service electrostatic discharge (ESD) kit. When connecting a bonding wire, ensure that it is connected to bare
metal and never to a painted or non-metal surface. The wrist strap should be secure and in full contact with your skin, and
ensure that you remove all jewelry such as watches, bracelets, or rings prior to bonding yourself and the equipment.

Enter service mode

Service Mode allows you to immediately cut the power from the computer without disconnecting the battery cable or removing
the battery from the computer.
Steps
1. Shut down the computer and disconnect the AC adapter from the computer.
2. Press and hold the <B> key on the keyboard, and then press the power button for 3 seconds until the Dell logo appears on
the screen.
The computer restarts and the following screed in displayed.
8 Working inside your computer