Hardware Maintenance Manual
ThinkPad L420, L421, and L520
Second Edition April Copyright Lenovo
Contents
Locations 113
ThinkPad L421
About this manual
ThinkPad L420
ThinkPad L520
Iv Hardware Maintenance Manual
Safety information
General safety
Electrical safety
Safety inspection guide
Safety notices multilingual translations
Grounding requirements
Safety information
Hardware Maintenance Manual
Perigo
Perigo
Safety information
Vorsicht
Vorsicht
Hardware Maintenance Manual
Safety information
Hardware Maintenance Manual
Safety information
Hardware Maintenance Manual
Safety information
Laser compliance statement multilingual translations
Safety information
Hardware Maintenance Manual
Safety information
Hardware Maintenance Manual
Safety information
Hardware Maintenance Manual
Important service information
Strategy for replacing FRUs
Strategy for replacing a hard disk drive
How to use error message
Important notice for replacing a system board
FRU identification for CTO, CMV, and GAV products
General Announce Variant GAV
Hardware Maintenance Manual
General checkout
What to do first
Diagnostics using PC-Doctor for DOS
Checkout guide
Testing the computer
Diagnostics Interactive Tests
Detecting system information with PC-Doctor
FRU tests
Lenovo ThinkVantage Toolbox
Applicable test
Power system checkout
Checking the ac power adapter
Checking operational charging
Checking the battery pack
Pin Voltage V dc
Wire Voltage V dc
Checking the backup battery
Terminal Voltage V dc
Related service information
Restoring the factory contents by using Recovery Disc Set
Power-on password
Passwords
Hard-disk password
How to remove the power-on password
Supervisor password
How to remove the hard-disk password
Screen blank mode
Power management
Sleep standby mode
Hibernation mode
Symptom-to-FRU index
Numeric error codes
0251 Charge the backup battery for more than 8 hours
0250 Charge the backup battery for more than 8 hours
By connecting the ac power adapter
0260 Charge the backup battery for more than 8 hours
No-beep symptoms
Error messages
LCD-related symptoms
Reseat the LCD connectors
Intermittent problems
Undetermined problems
See important note for LCD-related symptoms
Hardware Maintenance Manual
Status indicators
Status indicators
Indicator Meaning
Fn key combinations
Key combination Description
For Windows
For Windows Vista and Windows XP
Fn key combinations
Hardware Maintenance Manual
FRU replacement notices
Screw notices
Retaining the Uuid
Retaining serial numbers
Restoring the serial number of the system unit
MTM on rear label
Reading or writing the ECA information
Eeprom
Hardware Maintenance Manual
Important notice for replacing a battery pack
Battery pack
Removing and replacing a FRU
ExpressCard blank bezel and Media Card blank bezel
Removal steps of Media Card blank bezel
For access, remove this FRU Battery pack on
Optical drive or travel cover
Thermal cover
Step Screw quantity Color Torque
Hard disk drive or solid state drive assembly
Removal steps of HDD or SSD assembly
When installing
Dimm
Fan assembly
Removal steps of fan assembly
Removal steps of fan assembly
1080 CPU
Removal steps of CPU
SIM slot cover
Removal steps of SIM slot cover
WAN
M2 × 3 mm, flat-head, nylon-coated Black 181 Nm Kgfcm
MSATA solid state drive
Palm rest assembly with cables
Removal steps of palm rest assembly with cables
Removal steps of palm rest assembly with cables
Removal steps of palm rest assembly with cables
PCI Express Mini Card for wireless LAN
Removal steps of PCI Express Mini Card for wireless LAN
Step Screw quantity Color Torque
Backup battery
Bluetooth daughter card
Removal steps of Bluetooth daughter card
Hardware Maintenance Manual
Keyboard
Removal steps of keyboard
Keyboard bezel
Removal steps of keyboard bezel
LCD unit
Removal steps of LCD unit
For ThinkPad L520 models For ThinkPad L420 and L421 models
Top shielding assembly
For ThinkPad L520 models Step Screw quantity Color Torque
Removal steps of top shielding assembly
System board assembly
Important notices for handling the system board
Hardware Maintenance Manual
Removing and replacing a FRU
Hardware Maintenance Manual
Removal steps of system board assembly
USB connector board and USB cable assembly
For ThinkPad L520 models
DC-in cable and base cover
Removal steps of DC-in cable and base cover
Applying labels to the base cover
LCD front bezel
Speaker assembly
Integrated camera
Antenna assembly
Removal steps of antenna assembly
Hinges, LCD panel, LCD cable, and LCD rear cover assembly
Step Screw quantity Color Torque
M2 × 3 mm, flat-head, nylon-coated Black 181 Nm Kgfcm
Removing and replacing a FRU
Hardware Maintenance Manual
Locations
Front view
Rear view
Bottom view
Parts list
External CRU statement to customers
Overall
CRU
FRU Overall FRU no
CRU
CRU
CRU
CRU
CRU
CRU
DVD-RAM/RW drive 04W1268
DVD-RAM/RW drive 04W1269
CRU
CRU
CRU
CRU
CRU
CRU
CRU
CRU
CRU
CRU
CRU
CRU
CRU
CRU
CRU
CRU
CRU
WAN
LCD FRUs
Parts list
FRU 14.0-inch HD LCD FRU no
CRU
FRU 15.6-inch HD LCD FRU no
CRU ID
CRU ID
FRU 15.6-inch HD+ LCD FRU no
CRU
Language FRU no
Miscellaneous parts
Ac power adapters
Power cords
Country or region FRU no
Recovery discs Windows XP Professional 32 bit DVDs
Language
Windows Vista Business 32 bit DVDs
Windows Vista Home Basic 32 bit DVDs
US English 03W8061
Windows 7 Home Basic 32 bit DVDs
Windows 7 Home Premium 32 bit DVDs
Windows 7 Home Premium 64 bit DVDs
5016-CTO 5017-CTO 5019-CTO 7859-CTO 7860-CTO
Windows 7 Professional 32 bit DVDs
Windows 7 Professional 64 bit DVDs
Parts list-Windows 7 Professional 64 bit recovery DVDs
Windows 7 Ultimate 64 bit DVDs
Windows 7 Ultimate 32 bit DVDs
Windows 7 Starter 32 bit DVDs
Common service tools
Tool
Hardware Maintenance Manual
Appendix A. Notices
Electronic emissions notices
Trademarks
Page
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