Dell 15-N5040, 15-N5050, M5040/15 manual Before You Begin

CAUTION: Only a certified service technician should perform repairs on your computer. Damage due to servicing that is not authorized by Dell is not covered by your warranty.

CAUTION: When you disconnect a cable, pull on its connector or on its pull-tab, not on the cable itself. Some cables have connectors with locking tabs; if you are disconnecting this type of cable, press in on the locking tabs before you disconnect the cable. As you pull connectors apart, keep them evenly aligned to avoid bending any connector pins. Also, before you connect a cable, ensure that both connectors are correctly oriented and aligned.

CAUTION: To avoid damaging the computer, perform the following steps before you begin working inside the computer.

1Ensure that the work surface is flat and clean to prevent the computer cover from being scratched.

2Turn off your computer. See "Turning Off Your Computer" on page 10 and all attached devices.

CAUTION: To disconnect a network cable, first unplug the cable from your computer and then unplug the cable from the network device.

3Disconnect all telephone or network cables from the computer.

4Press and eject any installed cards from the 3-in-1 media card reader.

5Disconnect your computer and all attached devices from their electrical outlets.

6Disconnect all attached devices from your computer.

CAUTION: To help prevent damage to the system board, remove the main battery, see "Removing the Battery" on page 13, before working inside the computer.

7Remove the battery. See "Removing the Battery" on page 13.

8Turn the computer top-side up, open the display, and press the power button to ground the system board.

Before You Begin

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