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