Dell NOT21684 Owner's Manual page 51

NOTE:
If battery is not a pre-requisite and if you have disconnected the battery cable, ensure to connect the battery cable. To
connect the battery cable, follow step 1 and step 2 in the procedure.
Steps
1. Connect the battery cable to the connector on the system board.
2. Align the screw holes on the base cover with the screw holes on the palm-rest and keyboard assembly, and then snap the
base cover into place.
3. Tighten the eight captive screws that secure the base cover to the palm-rest and keyboard assembly.
Next steps
1. Install the SIM card.
2. Follow the procedure in
NOTE: Ensure that your computer is in Service Mode. For more information, see
50 Removing and installing Customer Replaceable Units (CRUs)
After working inside your computer.
Before working inside your computer