™ Dell™ Latitude™ LS Portable Computers SERVICE MANUAL www.dell.
™ Dell™ Latitude™ LS Portable Computers SERVICE MANUAL www.dell.
____________________ Information in this document is subject to change without notice. © 1999 Dell Computer Corporation. All rights reserved. Reproduction in any manner whatsoever without the written permission of Dell Computer Corporation is strictly forbidden. Trademarks used in this text: Dell, the DELL logo, and Latitude are trademarks of Dell Computer Corporation.
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 . . . . . . . . . . . . . . . . . .
Figures Table vi Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. Figure 8. Figure 9. Figure 10. Figure 11. Figure 12. Figure 13. Figure 14. Figure 15. Figure 16. Figure 17. Figure 18. Figure 19. Figure 20. Figure 21. Figure 22. Figure 23. Figure 24. Computer Orientation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Main Battery Assembly Removal . . . . . . . . . . . . . . . . . . . . . . . 3 Screw Identification . . . . . . . . . . . . . . . . . . . . . . . . .
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Read This First A prerequisite for using this manual to service Dell computer systems is a basic knowledge of PCs and prior training in PC troubleshooting techniques. In addition to information provided in this manual, Dell provides the User’s Guide for troubleshooting procedures and instructions on using the Dell Diagnostics to test the computer system. 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.
Dell™ Latitude™ LS Portable Computers Service Manual This manual provides instructions for removing and replacing field-replaceable components, assemblies, and subassemblies in your Dell Latitude portable 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.
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.
battery battery latch 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.
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 Bezel: Hard-Disk Drive Assembly: Display Assembly Hinge to Base: M2 x 4 mm (2 each) M2 x 4 mm (4 each) M2 x 3.5 mm (6 each) Rubber Screw Covers (4 each) LCD Panel and Inverter: Display Assembly Hinges: Keyboard Assembly: M2 x 3.5 mm (5 each) M2.
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 following steps: 1.
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 audio I/O port cover system board assembly speaker fan APR docking doors bottom case assembly main battery Figure 5. Exploded View—Computer The following subsections provide instructions for removing and replacing field-replaceable parts and assemblies.
Hard-Disk Drive Assembly M2 x 4-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 avoid dropping it. NOTICE: Make sure that the work surface is clean to prevent scratching the computer cover. 1.
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, a very small flat-blade screwdriver, or a tool of similar size in the keyboard bezel hole and carefully push down (see Figure 7). 2.
Display Assembly display assembly M2 x 8.5-mm screw left hinge cover LCD flex-cable hold-down clip right hinge cover M2 x 4-mm screws (4) LCD flex cable 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 M2 x 4-mm screws at the back of the computer that secure the display assembly to the bottom case (see Figure 8). 4.
5. Remove the two M2 x 4-mm screws at the bottom of the computer that secure the display assembly to the bottom case (see Figure 8). 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.
6. Reinstall the two M2 x 4-mm screws that secure the display assembly to the bottom case. You may have to squeeze the display assembly and the bottom assembly together, so the screw holes align in the base assembly and the hinge posts. Do not completely tighten the screws. 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.
Display Assembly Bezel l large rubber screw covers (6) display assembly bezel M2 x 3.5-mm screws (6) LCD panel back light plug latch left hinge M2 x 3.5-mm screw M2.6 x 4-mm screws (4) inverter display-assembly top cover right hinge Figure 9. Display Assembly Bezel Removal NOTICE: To avoid damaging the system board, you must remove the main battery before you service the computer. 1.
3. Separate the bezel from the display-assembly top cover. The bezel is secured by slot openings that snap into the display-assembly top cover. Carefully lift the inside edge of the bezel, working your way around the inside perimeter, to unsnap and remove the bezel from the display assembly. Display Assembly Latch display assembly latch display assembly top cover latch spring post Figure 10.
LCD Panel LCD panel back light plug M2 x 3.5-mm screws (4) narrow flex cable M2 x 3.5-mm screw ZIF connector wide flex cable inverter inverter back light plug narrow flex cable Figure 11. LCD Panel Removal NOTICE: To avoid damaging the system board, you must remove the main battery before you service the computer. 1. Ground yourself by touching the unpainted metal surface of the I/O panel on the back of the computer. 2. Remove the keyboard bezel. 3. Remove the display assembly. 4.
8. Disconnect the narrow flex cable from the ZIF connector on the left side of the inverter. 9. Disconnect the two-wire back-light plug from the connector on the right side of the inverter (see Figure 11). 10. Remove the inverter. 11. Lift the LCD panel from the bottom edge, giving enough room to fit your hand between the LCD panel and the top cover. 12. Carefully peel the LCD flex cable away from the top cover. 13. Lift the LCD panel out of the top cover. 14.
6. With bezel side of the inverter facing down, connect the two-wire back-light plug to the connector on the right side of the inverter. When the plug is all the way in the connector, the key slot in the center of the plug should not be visible. If you can see the key slot, the plug is not in the connector correctly. Pull the plug out, turn the plug over, and reinsert it into the connector. 7. Roll the inverter over (away from you), so the bezel side of the inverter is up. 8.
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 assembly (see Figure 9).
NOTICE: The keycaps on the keyboard are fragile, easily dislodged, and time-consuming to replace. Be careful when removing and handling the keyboard. 6. Remove the keyboard assembly. To replace the keyboard assembly, perform the following steps. NOTICE: Position the keyboard cable so it is not twisted when it is connected to the system board. 1. Connect the keyboard cable to the connector on the system board. NOTE: Five metal tabs retain the bottom of the keyboard in the palmrest assembly. 2.
Memory Module memory module inner tabs (2) Figure 13. Memory Module Removal NOTICE: To avoid damaging the system board, you must remove the main battery before you service the computer. 1. Remove the keyboard bezel. 2. Remove the keyboard assembly. 3. Ground yourself by touching the unpainted metal surface of an I/O connector on the computer’s back panel. 4.
If you do not hear a click as each end of the memory module snaps into the tabs, remove the memory module and reinstall it. Palmrest Assembly M2.6 x 1.6-mm screws (6) Figure 14. Removing the Palmrest Assembly Bottom Screws The palmrest assembly consists of the palmrest, status lights, and touch pad assembly. NOTICE: To avoid damaging the system board, you must remove the main battery before you service the computer. 1. Remove the keyboard bezel. 2. Remove the display assembly. 3.
M2 x 6-mm screws (3 silver) M2 x 4-mm screws (4 black) palmrest assembly Figure 15. Removing the Palmrest Assembly Top Screws 8. Remove the three silver M2 x 6-mm screws in the keyboard-assembly area that secure the middle of the palmrest assembly to the bottom case (see Figure 15). 9. Disconnect the status lights flex cable from the ZIF connector on the system board. 10. Disconnect the touch pad flex cable from the ZIF connector on the system board. 11.
3. Reinstall the four black M2 x 4-mm screws that secure the top of the palmrest assembly to the bottom-case assembly (see Figure 15). 4. Connect the touch pad flex cable to the ZIF connector on the system board. 5. Connect the status lights flex cable to the ZIF connector on the system board. 6. Turn the computer upside down. 7. Reinstall the six M2.6 x 1.6-mm screws in the battery bay that secure the bottom of the palmrest assembly to the bottom-case assembly (see Figure 14). 8.
8. Disconnect the flex cable from the ZIF connector on the back of the touch pad (see Figure 16). The flex cable remains attached to the touch pad holder assembly. Bottom Assembly fan speaker (shown with audio EMI shield removed) RTC battery modem main battery release latch location main battery compartment reserve battery system board assembly bottom case cover Figure 17.
Reserve Battery reserve battery reserve battery cable Figure 18. Reserve Battery Removal NOTICE: The reserve battery provides power to the computer’s nonvolatile random-access memory (NVRAM) when the computer is turned off. Removing the battery causes the computer to lose the user-settable parameters in NVRAM. If possible, make a copy of this information before you remove the reserve battery. 1. Remove the keyboard bezel. 2. Remove the keyboard assembly. 3.
3. Grasp the RTC battery and pull it out of the holder. You may need to used a small flat-blade screwdriver to carefully pry the battery out of the holder. Main Battery See the “Preparing to Work Inside Your Computer” section found earlier in this manual for detailed instructions for removing the battery. Modem M2 x 8.5-mm screw modem modem retainer bracket Figure 19. Modem Removal 1. Remove the keyboard bezel. 2. Remove the display assembly. 3. Remove the keyboard assembly. 4.
7. Remove the M2 x 8.5-mm screw that secures the modem retainer bracket and modem to the system board (see Figure 19). The screw is located by the VGA port. 8. Remove the modem retainer bracket from the system board. 9. Pull the modem straight up to disconnect it from the system board. 10. Disconnect the modem cable from the connector on the system board. To replace the modem, perform the following steps: 1. Connect the modem cable to the connector on the system board. 2.
Fan M2 x 3.5-mm screws (2) fan connector Figure 20. Fan Removal 1. Remove the keyboard bezel. 2. Remove the display assembly. 3. Remove the keyboard assembly. 4. Remove the palmrest assembly. 5. Carefully disconnect the fan wire connector from the system board (see Figure 20). The male connector on the fan wire is keyed to fit into the female connector one way only. 6. Remove the two M2 x 3.5-mm screws that secure the fan to the bottom assembly (see Figure 20). 7.
4. Replace the palmrest assembly. 5. Replace the keyboard assembly. 6. Replace the display assembly. 7. Replace the keyboard bezel. Speaker audio EMI shield M2 x 3.5-mm screws (2) EMI adhesive sponge speaker speaker wire connector Figure 21. Speaker Removal 1. Remove the keyboard bezel. 2. Remove the display assembly. 3. Remove the keyboard assembly. 4. Remove the palmrest assembly. NOTICE: To ensure maximum cooling for the microprocessor, do not touch the glue side of the thermal conductive tape.
NOTICE: The audio EMI shield is attached to the USB connector housing with two-sided tape. To avoid bending the audio EMI shield, care must be taken when separating the audio EMI shield from the USB connector housing. 6. Using a small flat-blade screwdriver, carefully separate the audio EMI shield away from the USB connector housing. Place the edge of the screwdriver between the audio EMI shield and the USB connector housing, and slowly pry the two apart. 7.
7. Reinstall the palmrest assembly. 8. Reinstall the keyboard assembly. 9. Reinstall the display assembly. 10. Reinstall the keyboard bezel. System Board Assembly 6 EMI adhesive sponge audio EMI shield RTC battery M2 x 8.5-mm screw modem retainer bracket USB connector modem system board M2 x 3.5-mm screws (6) thermal cooling solution fan assembly fan wire connector speaker EMI clip location PC Card cover reserve battery bottom case assembly M2 x 4-mm screws (2) audio I/O port cover Figure 22.
NOTICE: The processor is not replaceable. Do not attempt to remove the thermal cooling solution. 1. Remove the keyboard bezel. 2. Remove the display assembly. 3. Remove the keyboard. 4. Remove the palmrest assembly. 5. Use a 5-mm socket wrench to remove the four 5-mm socket screws for the VGA and parallel ports located on the back of the bottom case assembly. 6.
14. Disconnect the speaker wire from the connector on the system board assembly. 15. Disconnect the fan wire from the connector on the system board assembly. 16. Lift the system board assembly out of the bottom case assembly. To replace the system board assembly, perform the following steps: 1. Transfer the memory module(s) to the replacement system board assembly. 2. Place the new hard-disk drive EMI clip on the system board assembly (see Figure 23). M2 x 3.5-mm screw hard-disk drive EMI clip Figure 23.
9. Reinstall the audio EMI shield. a. Carefully position the audio EMI shield so the section with the two-sided tape is over the USB connector housing. b. Press the audio EMI shield down so it attaches to the USB connector housing. c. Reattach the EMI adhesive sponge across the thermal cooling solution. 10. Reinstall the two IDE connector screws at both ends of the IDE (media bay) connector located on the back of the bottom case assembly. 11.
1. Remove the keyboard bezel. 2. Remove the display assembly. 3. Remove the keyboard. 4. Remove the palmrest assembly. 5. Remove the system board. NOTICE: The tabs on the release button are plastic. Care should be taken when squeezing the tabs to avoid breaking them. 6. Using needle-nose pliers, gently squeeze the two tabs on the back of the release button together and grasp the top of the battery release latch and gently pull up to free it from the release button assembly (see Figure 24). 7.
NOTE: On the under side of the doors, a small F is printed on the front door and a small B is printed on the back door. As you hold the doors for installation, the front door is near you, the back door is away from you, and the tension spring is to the left. 1. Turn the computer upside down. The APR connector door opening should be at the top. 2.
36 Dell Latitude LS Portable Computers Service Manual
Index A H APR docking doors removal, 34 hard-disk drive assembly removal, 7 hinge removal, 16 B bottom assembly components, 23 illustrated, 23 D display assembly bezel removal, 12 hinge removal, 16 latch removal, 13 removal, 9 K keyboard assembly removal, 17 L latch removal, 13 LCD panel removal, 14 M F main battery release latch removal, 34 removal, 3, 25 fan removal, 27 memory module removal, 19 field-replaceable parts and assemblies illustrated, 6 modem removal, 25 G P palmrest assembly
R T reserve battery removal, 24 tools, 2 RTC battery removal, 24 touch pad removal, 22 S Z screw identification and tightening, 3 ZIF connectors, 5 speaker removal, 28 system board assembly illustration, 30 removal, 30 2 Dell Latitude LS Portable Computers Service Manual
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