dell latitude l400 User Manual

www.dell.com
Dell™ Latitude™ L400 
SERVICE MANUAL 

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 situation...

v
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 ....

support.dell.comDell Latitude L400 Service Manual  1
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 other wise 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...

2 Dell Latitude L400 Service Manual
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...

support.dell.com Dell Latitude L400 Service Manual 3
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...

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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
Hard-Disk Drive 
Assembly:
M3 x 3 mm
(2 each, black)
Display Assembly 
Hinge to Base:
M2 x 4 mm 
(2 each, black)
M2 x 4.5 mm 
(2 each, silver)
Display Assembly 
Bezel:
M2 x 3.5 mm (6 each)
Rubber Screw Covers 
(6 each)
LCD Panel and 
Inverter:
M2 x 3.5 mm (5...

support.dell.com Dell Latitude L400 Service Manual 5
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).
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...

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Removing Field-Replaceable Parts 
and Assemblies     
Figure 5.  Exploded View—Computer
display 
assembly
keyboard
palmrest 
assembly
system board assembly
hard-disk drive
main batter ybottom case assembly
right hinge cover
left hinge cover
audio EMI 
shield
audio I/O port cover
keyboard bezel
speaker
fan
APR docking 
doors
modem