Service Manual
Table Of Contents
- Latitude 3420 Service Manual
- Working inside your computer
- Removing and installing components
- Recommended tools
- Screw List
- Major components of your system
- MicroSD-card
- SIM card tray
- Base cover
- Battery cable
- Battery
- Memory module
- M.2 solid-state drive thermal plate
- M.2 solid-state drive conversion bracket
- M.2 solid-state drive
- Hard-disk drive
- WLAN card
- WWAN card
- I/O cable
- Display assembly
- System fan
- Heatsink assembly
- Power adapter port
- Coin-cell battery
- USB cable
- Ethernet port
- I/O board
- Power-button board
- System board
- Speakers
- Touchpad
- WWAN I/O board
- Palmrest assembly
- Display bezel
- Display panel
- Camera
- Display cable
- Display back-cover
- Drivers and downloads
- System setup
- Troubleshooting
- Built-in self-test (BIST)
- LCD Built-in Self Test (BIST)
- Dell SupportAssist Pre-boot System Performance Check diagnostics
- Diagnostic LED behavior
- Diagnostic error messages
- System error messages
- Recovering the operating system
- Real-Time Clock (RTC Reset)
- Flashing the BIOS
- Backup media and recovery options
- WiFi power cycle
- Flea power release
- Getting help and contacting Dell
WWAN I/O board
Removing the WWAN I/O board
Prerequisites
1. Follow the procedure in before working inside your computer.
2. Remove the microSD card.
3. Remove the SIM card tray for 4G LTE enabled systems.
4. Remove the base cover.
5. Remove the battery cable.
About this task
The following image indicates the location of the WWAN I/O board and provides a visual representation of the removal
procedure.
NOTE: The following steps are applicable only for 4G LTE enabled systems.
Steps
1. Remove the two (M2x3) screws that secure the WWAN I/O board to the palmrest assembly.
2. Gently flip the WWAN I/O board toward right.
3. Open the latch and disconnect the WWAN cable from the connector on the WWAN I/O board.
4. Lift and remove the WWAN I/O board from the palmrest assembly.
Installing the WWAN I/O board
Prerequisites
If you are replacing a component, remove the existing component before performing the installation procedure.
Removing and installing components
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