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Dell Latitude L400
SERVICE MANUAL
www.dell.com
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Notes, Notices, and Cautions Throughout this guide, blocks of text may be accompanied by an icon and printed in bold type or in italic type. These blocks are notes, notices, and cautions, and they are used as follows: NOTE: A NOTE indicates important information that helps you make better use of your computer system. NOTICE: A NOTICE indicates either potential damage to hardware or loss of data and tells you how to avoid the problem. CAUTION: A CAUTION indicates a potentially hazardous situat
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Contents Recommended Tools. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Preparing to Work Inside Your Computer . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 Screw Identification and Tightening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 ZIF Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Removing Field-Replaceable Parts and Assemblies . . . . . . . . . . . . .
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Figure 6. Hard-Disk Drive Assembly Removal . . . . . . . . . . . . . . . . . . . . . . . 7 Figure 7. Keyboard Bezel Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Figure 8. Display Assembly Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Figure 9. Display Assembly Bezel Removal . . . . . . . . . . . . . . . . . . . . . . . . 11 Figure 10. Display Assembly Latch Removal . . . . . . . . . . . . . . . . . . . . . . . . 12 Figure 11. LCD Panel Removal
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Dell Latitude L400 Service Manual This manual provides instructions for removing and replacing field-replaceable components, assemblies, and subassemblies in your Dell Latitude computer. Unless otherwise noted, each procedure in this manual assumes the following conditions: The computer and any attached peripherals are turned off, and the peripherals are disconnected from the I/O panel on the back and right side of the computer. A part can be replaced by performing the removal proced
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Recommended Tools Most of the procedures in this manual require the use of one or more of the following tools: #0 and #1 magnetized Phillips-head screwdrivers Small flat-blade screwdriver 5-mm socket wrench Small plastic scribe Needle-nose pliers Preparing to Work Inside Your Computer Before you start to work on the computer, perform the following steps: 1. Save any work in progress and close all open application programs. 2. Turn off the computer and any attached peripherals. NOTE: M
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battery latch battery Figure 2. Main Battery Assembly Removal 9. Ground yourself by touching the unpainted metal surface of an I/O connector on the back of the computer. NOTICE: While you work, periodically touch the I/O panel to dissipate any static electricity that might harm components. Screw Identification and Tightening The illustrations in the following removal procedures provide lengths of the correct screws for each procedure. Figure 3 shows examples. Match the actual
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When you are removing and replacing components, photocopy the Table 1 placement mat as a tool to lay out and keep track of the component screws. Table 1. Screw Placement Mat With Component Screw Counts and Sizes Display Assembly Display Assembly Hinge to Base: Hard-Disk Drive Bezel: M2 x 4 mm Assembly: (2 each, black) M2 x 3.5 mm (6 each) M3 x 3 mm M2 x 4.5 mm Rubber Screw Covers (2 each, black) (2 each, silver) (6 each) Display Assembly LCD Panel and Keyboard Inverter: Hinges: Assembl
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ZIF Connectors Some of the computer’s interface connectors are zero insertion force (ZIF) connectors. These connectors are not removable, but they must be released to disconnect a cable from them (see Figure 4). movable part of connector (do not remove) Figure 4. Disconnecting an Interface Cable NOTICE: The ZIF connectors are fragile. To avoid damage, do not apply too much pressure to the movable part of the connector. To disconnect an interface cable from a ZIF connector, perform the foll
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Removing Field-Replaceable Parts and Assemblies display assembly left hinge cover keyboard keyboard bezel right hinge cover palmrest assembly hard-disk drive audio EMI shield modem system board assembly audio I/O port cover speaker fan APR docking doors bottom case assembly main battery Figure 5. Exploded ViewComputer 6 Dell Latitude L400 Service Manual
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The following subsections provide instructions for removing and replacing field-replaceable parts and assemblies. Hard-Disk Drive Assembly M3 x 3-mm screws (2) hard-disk drive bottom of computer Figure 6. Hard-Disk Drive Assembly Removal NOTICE: To avoid damaging the system board, you must remove the main battery before you service the computer. NOTICE: The hard-disk drive is very sensitive to shock. Handle the assembly by its edges (do not squeeze the top of the hard-disk drive case), and
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Keyboard Bezel microphone hole keyboard bezel keyboard bezel release hole Figure 7. Keyboard Bezel Removal NOTICE: To avoid damaging the system board, you must remove the main battery before you service the computer. NOTICE: To avoid damaging the microphone, do not put any objects into the microphone hole (see Figure 7). 1. Place the point of a paper clip or a tool of similar size in the keyboard bezel hole and carefully push down (see Figure 7). 2. While pushing down, slide the keyboard bez
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Display Assembly display assembly M2 x 9.5-mm screw left hinge cover LCD flex-cable hold-down clip LCD flex cable right hinge cover M2 x 4-mm screws (2) M2 x 4.5-mm screws (2) Figure 8. Display Assembly Removal NOTICE: To avoid damaging the system board, you must remove the battery before you service the computer. 1. Remove the keyboard bezel. 2. Close the display. 3. Remove the two silver M2 x 4-mm screws at the back of the computer that secure the display assembly to the bottom case (see
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6. Turn the computer right-side up. 7. Open the display. 8. Remove the left and right hinge covers. NOTE: When replacing the display assembly, the left hinge cover must go over the left hinge and the right hinge cover must go over the right hinge. They are not interchangeable. An L is stamped on the bottom of the left hinge cover and an R is stamped on the bottom of the right hinge cover. 9. Remove the M2 x 9.5-mm screw that secures the LCD flex-cable hold-down clip and the LCD flex
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7. Reinstall the two M2 x 4-mm screws in the back of the computer that secure the display assembly to the back of the bottom case. 8. Tighten the two screws that you installed in step 6. 9. Open the display and reinstall the left and right hinge covers. An L is stamped on the bottom of the left hinge cover and an R is stamped on the bottom of the right hinge cover. Display Assembly Bezel l large rubber screw covers (6) display assembly bezel M2 x 3.5-mm screws (6) LCD panel latch back light pl
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NOTICE: To avoid damaging the system board, you must remove the main battery before you service the computer. 1. Use a scribe to carefully pry the six rubber screw covers out of the six screw holes located along the top and bottom of the bezel on the front of the display assembly (see Figure 9). 2. Remove the six M2 x 3.5-mm screws located at the top and bottom of the bezel on the front of the display assembly (see Figure 9). 3. Separate the bezel from the display-assembly top cover. The bez
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To replace the display-assembly latch, perform the following steps: 1. Carefully place the latch spring over the post on the display-assembly top cover. You may need to use a small flat-blade screwdriver to place the spring over the post. Hold the spring on the post with the screwdriver while performing the next step. 2. Holding the latch, stretch the spring slightly and set the display-assembly latch in place in the display assembly top cover. 3. Reinstall the bezel. LCD Panel LCD panel
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2. Remove the keyboard bezel. 3. Remove the display assembly. 4. Remove the display assembly bezel. 5. Remove the four M2 x 3.5-mm screws on the left and right sides of the display assembly that secure the LCD panel to the top cover (see Figure 11). 6. Remove the M2 x 3.5-mm screw that secures the inverter to the top cover. 7. Lift and roll the inverter over (toward you), so the bezel side is down and the connector side is up (see Figure 11). 8. Disconnect the narrow flex
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b. Lower the bottom end of the LCD panel into the top cover, making sure the LCD flex cable lines up with the opening that is to the right of the left hinge. c. Make sure the narrow part of the flex cable that goes to the inverter is visible at the bottom edge of the LCD panel. d. Press the LCD panel into the top cover. 5. Connect the narrow flex cable to the ZIF connector on the left side of the inverter. 6. With the connector side of the inverter facing up, connect the two-wire back-li
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Keyboard Assembly M2 x 4-mm screws (4) keyboard assembly keyboard cable Figure 12. Keyboard Assembly Removal To remove the keyboard assembly, perform the following steps. NOTICE: To avoid damaging the system board, you must remove the main battery before you service the computer. NOTICE: Make sure that the work surface is clean to prevent scratching the computer cover. 1. Remove the keyboard bezel. 2. Remove the four M2 x 4-mm screws located across the top of the keyboard assem