ThinkPad T420 and T420i Hardware Maintenance Manual
Fourth Edition November Copyright Lenovo
Contents
Chapter 9. Locations
Chapter 10. Parts list
Wireless LAN antenna assembly or wireless
ii ThinkPad T420 and T420i Hardware Maintenance Manual
About this manual
iv ThinkPad T420 and T420i Hardware Maintenance Manual
General safety
Chapter 1. Safety information
Electrical safety
Handling devices that are sensitive to electrostatic discharge
Safety inspection guide
Grounding requirements
DANGER
Safety notices multilingual translations
DANGER
DANGER
DANGER
6 ThinkPad T420 and T420i Hardware Maintenance Manual
DANGER
DANGER
PERIGO
Chapter 1. Safety information
PERIGO
PERIGO
PERIGO
PERIGO
DANGER
PERIGO
DANGER
DANGER
DANGER
DANGER
DANGER
DANGER
VORSICHT
VORSICHT
VORSICHT
VORSICHT
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Chapter 1. Safety information
14 ThinkPad T420 and T420i Hardware Maintenance Manual
Antes de encender el sistema despues de sustituir una FRU, compruebe que todos los tornillos, muelles y demás piezas pequeñas se encuentran en su sitio y no se encuentran sueltas dentro del sistema. Compruébelo agitando el sistema y escuchando los posibles ruidos que provocarían. Las piezas metálicas pueden causar cortocircuitos eléctricos
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Korean Spanish Traditional Chinese
Laser compliance statement multilingual translations
English Arabic Brazilian Portuguese French German Hebrew Japanese
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Chapter 1. Safety information
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Chapter 1. Safety information
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Before replacing parts
Chapter 2. Important service information
Strategy for replacing FRUs
Strategy for replacing a hard disk drive
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How to use error message
Important notice for replacing a system board
Using PEW
Strategy for replacing FRUs for CTO, CMV, and GAV Product definition
FRU identification for CTO, CMV, and GAV products
Dynamic Configure To Order CTO
To view the key commodities, do the following
1. Click Products & Service Warranty 2. Click Check Warranty Status
Using the HMM
This chapter presents following information
Chapter 3. General checkout
“Diagnostics using PC-Doctor for DOS” on page
“Power system checkout” on page
The following are not covered under warranty
What to do first
Checkout guide
Diagnostics using PC-Doctor for DOS
Testing the computer
If an error code appears, go to “Symptom-to-FRU index” on page
Windows VistaR and Windows XP
Lenovo ThinkVantage Toolbox
Detecting system information with PC-Doctor
Windows
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Table 1. FRU tests
FRU tests
The following table shows the test for each FRU
Checking operational charging
Power system checkout
Checking the ac power adapter
Checking the backup battery
Checking the battery pack
If the voltage is correct, replace the system board
If the voltage is not correct, replace the backup battery
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Applications and Drivers Recovery Disc one or more discs
Chapter 4. Related service information
Restoring the factory contents by using Recovery Disc Set
Operating System Recovery Disc one disc
2. Insert the Operating System Recovery Disc into the DVD drive
Passwords
Power-on password
Hard-disk password
B If an SVP has been set and is known by the service technician
Supervisor password
How to remove the power-on password
How to remove the hard-disk password
6. Select Master HDP
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Hibernation mode
Power management
Screen blank mode
Sleep standby mode
The system is powered off
Numeric error codes
Symptom-to-FRU index
Place the ThinkPad Notebook on a horizontal surface
Table 2. Numeric error codes continued
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Table 3. Error messages
Error messages
Table 4. Beep symptoms
Beep symptoms
No-beep symptoms
LCD-related symptoms
See important note for “LCD-related symptoms.”
Table 6. LCD-related symptoms
Symptom or error
Reseat the LCD connectors
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Intermittent problems
Undetermined problems
Chapter 5. Status indicators
Wireless LAN, Wireless WAN
Status indicators
Indicator
available while the microphone mute is on by default
Chapter 5. Status indicators
Table 7. Status indicators continued
The battery is being charged. When it reaches 20%, the blinking
the battery status indicator stops blinking, but the charging may
The ac power adapter is attached to the computer
Table 7. Status indicators continued
Description
Chapter 6. Fn key combinations
Table 8. Fn key combinations
Key combination
Table 8. Fn key combinations continued
Fn+PrtSc
Table 8. Fn key combinations continued
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Plastic to plastic
Chapter 7. FRU replacement notices
Screw notices
External CRU statement to customers
3. Select 2. Read S/N data from EEPROM
Retaining serial numbers
Restoring the serial number of the system unit
Torque driver
Product ID on rear label
Retaining the UUID
Reading or writing the ECA information
MTM on rear label
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DANGER
Chapter 8. Removing and replacing a FRU
External CRU statement to customers
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Before servicing ThinkPad T420 and T420i
Removal steps of battery pack DANGER
1010 Battery pack
Important notice for replacing a battery pack
Removal steps of ExpressCard blank bezel
1020 ExpressCard blank bezel
Removal steps of Serial Ultrabay Enhanced device or travel bezel
1030 Serial Ultrabay Enhanced device or travel bezel
Removal steps of hard disk drive and solid state drive
1040 Hard disk drive HDD and solid state drive SSD
Chapter 8. Removing and replacing a FRU
For HDD and HDD rubber rails 9.5 mm
For HDD and HDD rubber rails 7.0mm
For SSD and spacers
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Removal steps of DIMM slot cover
1050 DIMM slot cover
Removal steps of DIMM in the slot on the underside of the computer
1060 DIMM in the slot on the underside of the computer
Removal steps of PCI Express Mini Card for wireless WAN
1070 PCI Express Mini Card for wireless WAN
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Removal steps of keyboard
1080 Keyboard
Lift the keyboard a little in the direction shown by arrow
3 , and then detach the connector
Installation steps of keyboard
Chapter 8. Removing and replacing a FRU
is attached firmly
4. Make sure that the front edge of the keyboard
Removal steps of DIMM in the slot under the keyboard
1090 DIMM in the slot under the keyboard
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Removal steps of backup battery DANGER
1100 Backup battery
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Removal steps of PCI Express Mini Card for wireless LAN
1110 PCI Express Mini Card for wireless LAN
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When installing
1120 Keyboard bezel assembly, FPC cable, and Bluethooth daughter card
Color
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Step
Screw quantity
Chapter 8. Removing and replacing a FRU
When installing Make sure that the connector is attached firmly
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When installing Make sure that the connectors are attached firmly
Chapter 8. Removing and replacing a FRU
When installing Make sure that the connector is attached firmly
Removal steps of SmartCard
1130 SmartCard
Removal steps of SmartCard dummy spacer
When installing Make sure that the connector is attached firmly
Removal steps of modem daughter card MDC
1140 Modem daughter card MDC
Removal steps of speaker assembly
1150 Speaker assembly
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Removal steps of LCD unit
1160 LCD unit
Color
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Step
Screw quantity
Make sure that you attach the connectors firmly
When installing
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For Integreted Graphics models
1170 Fan assembly
Removal steps of fan assembly
For Discrete Graphics models
1a 1d 1c 1b
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For Discrete Graphics models
For Integrated Graphics models
For Integreted Graphics models When installing
For Discrete Graphics models
Make sure that the fan connector is attached firmly
Removal steps of CPU
1180 CPU
Removal steps of base cover assembly and DC-in connector cable
1190 Base cover assembly and DC-in connector cable
Color
When installing Make sure that the connector is attached firmly
Step
Screw quantity
Note Applying labels to the base cover
Wireless WAN MAC address label China mobile IMEI label
Removal steps of magnesium structure frame
1200 Magnesium structure frame
1.85 kgfcm
M2 × 8 mm, wafer-head, nylon-coated
Black
0.181 Nm
Removal steps of system board and ExpressCard slot assembly
1210 System board and ExpressCard slot assembly
Graphic Processing Unit GPU Discrete graphics chip
For Switchable Graphics models For Integrated Graphics models
Platform Controller Hub PCH
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1220 mSATA solid state drive
Color
Removal steps of mSATA solid state drive
Step
Screw quantity
Removal steps of LCD bezel assembly
2010 LCD bezel assembly
Removal steps of LED board
2020 LED board
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When installing Make sure that the connector is attached firmly
Removal steps of integrated camera
2030 Integrated camera
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Removal steps of LCD panel and LCD cable
2040 LCD panel and LCD cable
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When installing Make sure that the connector is attached firmly
Removal steps of camera cable
2050 Camera cable
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Torque
Step
Screw quantity
Color
Removal steps of hinges and LCD rear cover assembly
2070 Hinges and LCD rear cover assembly
Chapter 8. Removing and replacing a FRU
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Front view
Chapter 9. Locations
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External monitor connector Power jack USB connector
Rear view
Status indicators
DisplayPort connector USB connector RJ-45 Ethernet connector
LCD cover latch
Bottom view
Battery pack Battery pack latch DIMM slot Docking connector
“Recovery discs” on page “Common service tools” on page
Chapter 10. Parts list
This chapter contains following lists of the service parts
“Information about ac power adapters” on page “Power cords” on page
130 ThinkPad T420 and T420i Hardware Maintenance Manual
Overall
FRU Overall
Parts list-Overall
ThinkPad b/g/n Wireless 1x1 BGN
Intel Centrino Wireless-N
CRU ID
Table 9. Parts list-Overall continued
FRU Overall
FRU no
CRU ID
Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU no
Table 9. Parts list-Overall continued
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FRU Overall
CRU ID
Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU no
Table 9. Parts list-Overall continued
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FRU Overall
CRU ID
Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU no
Table 9. Parts list-Overall continued
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FRU Overall
CRU ID
Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU no
Table 9. Parts list-Overall continued
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FRU Overall
CRU ID
Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU no
Table 9. Parts list-Overall continued
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FRU Overall
CRU ID
Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU no
Table 9. Parts list-Overall continued
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FRU Overall
CRU ID
Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU no
Table 9. Parts list-Overall continued
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FRU Overall
CRU ID
Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU no
Table 9. Parts list-Overall continued
148 ThinkPad T420 and T420i Hardware Maintenance Manual
FRU Overall
CRU ID
Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU no
LCD FRUs
Table 10. Parts list-LCD FRUs
LCD bezel assembly
2 Camera module
Table 10. Parts list-LCD FRUs continued
No. FRU
FRU no
FRU no
Table 10. Parts list-LCD FRUs continued
152 ThinkPad T420 and T420i Hardware Maintenance Manual
FRU no
Table 10. Parts list-LCD FRUs continued
Table 11. Parts list-Keyboard
Keyboard
45N2160
Table 11. Parts list-Keyboard continued
Netherlands
45N2090
Table 12. Parts list-Miscellaneous parts
Miscellaneous parts
FRU no
Table 12. Parts list-Miscellaneous parts continued
Table 14. Parts list-3-pin ac power adapters
Information about ac power adapters
Table 13. Parts list-2-pin ac power adapters
Table 16. Parts list-3-pin power cords
Power cords
Table 15. Parts list-2-pin power cords
Windows Vista Business 32 bit SP2 DVDs
Recovery discs
Windows XP Professional DVDs
Windows 7 Professional 64 bit DVDs
Table 20. Parts list-Windows 7 Professional 32 bit recovery DVDs
Windows Vista Home Basic 32 bit SP2 DVDs
Windows 7 Professional 32 bit DVDs
4179-CTO, GBx, GEx
Windows 7 Home Premium 32 bit DVDs
Windows 7 Home Basic 32 bit DVDs
4178-CTO, 9Fx, 9Nx, A6x, BWx, CLx, CMx, CNx 4179-CTO, GMx, GNx
Table 23. Parts list-Windows 7 Home Premium 32 bit recovery DVDs
Table 24. Parts list-Windows 7 Home Premium 64 bit recovery DVDs
Windows 7 Home Premium 64 bit DVDs
Windows 7 Ultimate 64 bit DVDs
Table 25. Parts list-Windows 7 Ultimate 32 bit recovery DVDs
Table 26. Parts list-Windows 7 Ultimate 64 bit recovery DVDs
Windows 7 Ultimate 32 bit DVDs
Table 27. Parts list-Common service tools
Common service tools
Morrisville, NC U.S.A Attention Lenovo Director of Licensing
Appendix A. Notices
Lenovo United States, Inc 1009 Think Place - Building One
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Electronic emissions notices
Trademarks
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Part Number 0A6000703 1P P/N 0A6000703
0A6000703
