Reproduction in any manner whatsoever without the written permission of Dell Inc. is strictly forbidden.
Trademarks used in this text: Dell, the DELL logo, and Latitude are trademarks of Dell Inc.; Bluetooth is a trademark owned by Bluetooth SIG, Inc. and is used by Dell Inc. under
license.
Other trademarks and trade names may be used in this document to refer to either the entities claiming the marks and names or their products. Dell Inc. disclaims any
proprietary interest in trademarks and trade names other than its own.
Back to Contents Page Battery Latches Dell™ Latitude™ D420 Service Manual CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide. CAUTION: To prevent static damage to components inside your computer, discharge static electricity from your body before you touch any of your computer's electronic components.
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screw driver bracket securing tab shorter battery-latch assembly computer base Back to Contents Page ...
Hold a component such as a processor by its edges, not by its pins. NOTICE: 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.
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4. Disconnect all telephone or network cables from the computer. 5. Close the display and turn the computer upside down on a flat work surface. NOTICE: To avoid damaging the system board, you must remove the main battery before you service the computer. ...
Back to Contents Page Internal Card With Bluetooth® Wireless Technology Dell™ Latitude™ D420 Service Manual CAUTION: Before performing the following procedures, read the safety instructions in your Product Information Guide. NOTICE: To avoid electrostatic discharge, ground yourself by using a wrist grounding strap or by periodically touching a connector on the back panel of the computer.
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Back to Contents Page PC Card/Smart Card Reader Dell™ Latitude™ D420 Service Manual CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide. CAUTION: To prevent static damage to components inside your computer, discharge static electricity from your body before you touch any of your computer's electronic components.
Back to Contents Page Coin-Cell Battery Dell™ Latitude™ D420 Service Manual CAUTION: Before performing the following procedures, follow the safety instructions in your Product Information Guide. NOTICE: To avoid electrostatic discharge, ground yourself by using a wrist grounding strap or by periodically touching a connector on the back panel of the computer.
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You can increase your computer memory by installing memory modules on the system board. See "Specifications" in your computer User's Guide for information about the memory supported by your computer. Install only memory modules that are intended for your computer. NOTE: Memory modules purchased from Dell are covered under your computer warranty. CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide.
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8. Turn on the computer. As the computer boots, it detects the additional memory and automatically updates the system configuration information. To confirm the amount of memory installed in the computer, click Start® Help and Support® Dell System Information. Mini-Cards ...
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antenna cables (2) a. Disconnect the antenna cables from the WLAN card. NOTICE: To prevent damage to the connector, do not use tools to spread the securing clips. b. Release the card by pushing the metal securing clips toward the back of the computer until the card pops up slightly. c.
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Mobile Broadband (WWAN) Cards NOTE: Mobile Broadband cards may not be available in all regions. If you ordered a Mobile Broadband card with your computer, the card is already installed. CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide. ...
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NOTICE: To avoid damaging the Mobile Broadband card, never place cables on top of or under the card and ensure that you route the cables properly. NOTE: Cable routing for the Mobile Broadband card may vary. b. Align the card with the connector at a 45-degree angle, and press the card into the connector until you feel a click. 1 Mobile Broadband card 2 system board connector NOTE: For more specific information about which cable to connect to which connector, see the documentation that came with your Mobile Broadband...
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1 metal tabs (2) on SIM card slot 2 SIM card with cut-off corner NOTE: When you replace the SIM card, ensure that you slide the SIM card under the two metal tabs on the SIM card slot with the cut-off corner of the card facing toward the back of the computer.
Back to Contents Page Display Assembly Dell™ Latitude™ D420 Service Manual Removing the Display Assembly Removing the Display Bezel Removing the Display Panel Removing the Display-Panel Brackets Removing the Display Cable Removing the Display Latch CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide.
6. Pull on the display cable pull-tab toward the back of the computer to disconnect the display cable from the display connector on the system board. 7. Lift the display assembly away from the computer. Mini-Card antenna cables display cable display assembly NOTE: When you replace the display assembly, route the Mini-Card antenna cables through the system board and turn the computer upside down to...
1 M2 x 2 display 3 top 3-mm panel cover screws Removing the Display-Panel Brackets 1. Remove the four M2 x 3-mm screws (two on each bracket) from the display-panel brackets. display-panel brackets (2) M2 x 3-mm screws (4) display panel Removing the Display Cable 1 back of display-panel cable...
Removing the Display Latch M2 x 3-mm screws (2) screw holders (2) display latch metal plate display base Back to Contents Page ...
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Back to Contents Page Fan Dell™ Latitude™ D420 Service Manual CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide. CAUTION: To prevent static damage to components inside your computer, discharge static electricity from your body before you touch any of your computer's electronic components.
Back to Contents Page Flashing the BIOS Dell™ Latitude™ D420 Service Manual 1. Ensure that the AC adapter is plugged in and that the main battery is installed properly. NOTE: If you use a BIOS update program CD to flash the BIOS, set up the computer to boot from a CD before inserting the CD.
Back to Contents Page Hard Drive Dell™ Latitude™ D420 Service Manual Removing the Hard Drive Dismantling the Hard Drive Replacing the Hard Drive CAUTION: If you remove the hard drive from the computer when the drive is hot, do not touch the metal housing of the hard drive.
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The replacement hard drive ships with the protective cover and the hard drive cable. Only a certified service technician should dismantle the hard drive. Damage due to servicing that is not authorized by Dell is not covered by your warranty.
ZIF connector hard drive cable Replacing the Hard Drive NOTICE: Use firm and even pressure to slide the drive into place. If you use excessive force, you may damage the connector. 1. Follow the steps in Removing the Hard Drive in reverse order.
Back to Contents Page Hinge Cover Dell™ Latitude™ D420 Service Manual CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide. NOTICE: To avoid electrostatic discharge, ground yourself by using a wrist grounding strap or by periodically touching an unpainted metal surface (such as a connector on the back of the computer).
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Back to Contents Page Keyboard Dell™ Latitude™ D420 Service Manual CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide. NOTICE: To avoid electrostatic discharge, ground yourself by using a wrist grounding strap or by periodically touching an unpainted metal surface (such as a connector on the back of the computer).
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Back to Contents Page Modem Dell™ Latitude™ D420 Service Manual CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide. CAUTION: To prevent static damage to components inside your computer, discharge static electricity from your body before you touch any of your computer's electronic components.
Back to Contents Page Palm Rest Dell™ Latitude™ D420 Service Manual Removing the Palm Rest Replacing the Palm Rest Removing the Palm Rest CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide.
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M2.5 x 5-mm screws (6) NOTICE: Pull on the plastic tab on top of the connectors to avoid damaging the connectors. 11. Disconnect the speaker connector from the system board. 12. Disconnect the Secure Digital/SIM card reader cable from the system board. ...
Replacing the Palm Rest 1. Align the palm rest with the computer base and gently snap into place. 2. Connect the LED board connector to the system board. 3. Connect the touch pad connector to the system board. ...
Back to Contents Page Pin Assignments for I/O Connectors Dell™ Latitude™ D420 Service Manual USB Connector Video Connector USB Connector Signal USB5V+ USBP– USBP+ Video Connector Signal Signal CRT_R 9 CRT_G 10 CRT_B 11 MONITOR_DETECT– DDC_DATA CRT_HS...
Back to Contents Page Power Button Assembly Dell™ Latitude™ D420 Service Manual CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide. CAUTION: To prevent static damage to components inside your computer, discharge static electricity from your body before you touch any of your computer's electronic components.
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Back to Contents Page Suspend-Switch Sensor Board Dell™ Latitude™ D420 Service Manual CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide. CAUTION: To prevent static damage to components inside your computer, discharge static electricity from your body before you touch any of your computer's electronic components.
Back to Contents Page Wireless Switch Dell™ Latitude™ D420 Service Manual CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide. CAUTION: To prevent static damage to components inside your computer, discharge static electricity from your body before you touch any of your computer's electronic components.
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Back to Contents Page Speaker Dell™ Latitude™ D420 Service Manual CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide. NOTICE: To avoid electrostatic discharge, ground yourself by using a wrist grounding strap or by periodically touching an unpainted metal surface (such as the back panel) on the computer.
Back to Contents Page System Board Dell™ Latitude™ D420 Service Manual Removing the System Board Replacing the System Board Removing the System Board CAUTION: Before you begin any of the procedures in this section, follow the safety instructions in the Product Information Guide.
1 computer base 2 M2.5 x 5-mm screws (2) 3 system board assembly 4 power button connector 5 suspend-switch sensor board Replacing the System Board 1. Follow all of the steps in Removing the System Board in reverse order. NOTICE: Before turning on the computer, replace all screws and ensure that no stray screws remain inside the computer.
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Reproduction in any manner whatsoever without the written permission of Dell Inc. is strictly forbidden. Trademarks used in this text: Dell, the DELL logo, and Latitude are trademarks of Dell Inc.; Intel is a registered trademark of Intel Corporation; Bluetooth is a trademark owned by Bluetooth SIG, Inc. and is used by Dell Inc. under license.