Electrical safety Observe the following rules when working on electrical equipment. Important: Use only approved tools and test equipment. Some hand tools have handles covered with a soft material that does not insulate you when working with live electrical currents. Many customers have, near their equipment, rubber floor mats that contain small conductive fibers to decrease electrostatic discharges.
– Use caution; do not become a victim yourself. – Switch off power. – Send another person to get medical aid. Electronic emissions notices For electronic emission information on Class B digital devices, refer to the corresponding information in the User Guide. Safety inspection guide The purpose of this inspection guide is to assist you in identifying potentially unsafe conditions.
Handling devices that are sensitive to electrostatic discharge Any computer part containing transistors or integrated circuits (ICs) should be considered sensitive to electrostatic discharge(ESD). ESD damage can occur when there is a difference in charge between objects. Protect against ESD damage by equalizing the charge so that the machine, the part, the work mat, and the person handling the part are all at the same charge.
Safety notices (multilingual translations) The safety notices in this section are provided in the following languages: • English • Arabic • Brazilian Portuguese • French • German • Hebrew • Japanese • Korean • Spanish • Traditional Chinese DANGER Before the computer is powered on after FRU replacement, make sure all screws, springs, and other small parts are in place and are not left loose inside the computer.
Page 12
DANGER If the LCD breaks and the fluid from inside the LCD gets into your eyes or on your hands, immediately wash the affected areas with water for at least 15 minutes. Seek medical care if any symptoms from the fluid are present after washing.
Page 14
Antes de ligar o computador após a substituição da FRU, certifique-se de que todos os parafusos, molas e outras peças pequenas estejam no lugar e não estejam soltos dentro do computador. Verifique isso sacudindo o computador e procurando ouvir sons de peças soltas. Peças metálicas ou lascas de metal podem causar curto-circuito.
Page 15
Embora as principais baterias possuam baixa voltagem, uma bateria em curto-circuito ou aterrada pode produzir corrente o bastante para queimar materiais de pessoal ou inflamáveis. PERIGO A menos que uma hot swap seja permitida para a FRU que está sendo substituída, faça o seguinte antes de removê-la: desligue o computador, desconecte todos os cabos de energia das tomadas, remova o pacote de baterias e desconecte quaisquer cabos de interconexão.
Page 16
DANGER Si le panneau d'affichage à cristaux liquides se brise et que vous recevez dans les yeux ou sur les mains une partie du fluide, rincez-les abondamment pendant au moins quinze minutes. Consultez un médecin si des symptômes persistent après le lavage. DANGER Afin d'éviter tout risque de choc électrique, ne retirez pas le cache en plastique protégeant la partie inférieure de la carte d'alimentation.
Page 17
VORSICHT Akkus enthalten geringe Mengen von Nickel. Sie dürfen nicht zerlegt, wiederaufgeladen, kurzgeschlossen, oder Feuer oder Wasser ausgesetzt werden. Bei der Entsorgung die örtlichen Bestimmungen für Sondermüll beachten. Beim Ersetzen der Batterie nur Batterien des Typs verwenden, der in der Ersatzteilliste aufgeführt ist.
Page 18
Wenn ein Austausch der FRU bei laufendem Betrieb nicht erlaubt ist, gehen Sie beim Austausch der FRU wie folgt vor: Schalten Sie den Computer aus, ziehen Sie alle Netzkabel von den Netzsteckdosen ab, entfernen Sie den Akku und ziehen Sie alle miteinander verbundenen Kabel ab. ThinkPad T420 and T420i Hardware Maintenance Manual...
Page 20
ThinkPad T420 and T420i Hardware Maintenance Manual...
Page 21
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.
Page 22
Para evitar descargas, no quite la cubierta de plástico que rodea la parte baja de la tarjeta invertida. Aunque las baterías principales tienen un voltaje bajo, una batería cortocircuitada o con contacto a tierra puede producir la corriente suficiente como para quemar material combustible o provocar quemaduras en el personal.
Laser compliance statement (multilingual translations) The laser compliance statements in this section are provided in the following languages: • English • Arabic • Brazilian Portuguese • French • German • Hebrew • Japanese • Korean • Spanish • Traditional Chinese Chapter 1 Safety information...
Page 24
ThinkPad T420 and T420i Hardware Maintenance Manual...
UEFI BIOS and device driver fixes are customer-installable. The UEFI BIOS and device drivers are posted on the customer support site http://www.lenovo.com/support ® System Disassembly/Reassembly videos that show the FRU removals or replacements for the Lenovo authorized service technicians are available in the following support site: http://www.lenovoservicetraining.com/ion/ Advise customers to contact the Customer Support Center at 800-426-7378 if they need assistance in obtaining or installing any software fixes, drivers, and UEFI BIOS downloads.
Attention: The setup configuration on the computer you are servicing may have been customized. Running Automatic Configuration may alter the settings. Note the current configuration settings (using the View Configuration option); then, when service has been completed, verify that those settings remain in effect. Strategy for replacing a hard disk drive Always try to run a low-level format before replacing a hard disk drive.
MT and 3-digit model, where model = “CTO” (Example: 1829-CTO). Custom Model Variant (CMV) This is a unique configuration that has been negotiated between IBM or Lenovo and the customer. A unique 4-digit MT and 3-digit model is provided to the customer to place orders (Example: 1829-W15). A CMV is a special bid offering.
Page 32
PEW). • eSupport can be accessed at the following Web site: http://www.lenovo.com/support • To view the key commodities, click Download & Drivers. And then click Parts information. After that click Parts lookup. Type in the model type and serial number. The key commodities will be returned in the eSupport record under Parts shipped with your system.
“What to do first” on page 28 • “Checkout guide” on page 29 – “Diagnostics using PC-Doctor for DOS” on page 29 – “Lenovo ThinkVantage Toolbox” on page 31 – “FRU tests” on page 33 • “Power system checkout” on page 35 ®...
What to do first When you do return a FRU, you must include the following information in the parts exchange form or parts return form that you attach to it: 1. Name and phone number of service technician 2. Date of service 3.
PC-Doctor. Note: PC-Doctor for DOS is available at the following Web site: http://www.lenovo.com/support To create the PC-Doctor diagnostic CD, follow the instructions on the Web site. For some possible configurations of the computer, PC-Doctor might not run correctly. To avoid this problem, you need to initialize the computer setup by use of the ThinkPad Setup Utility before you run PC-Doctor.
Page 36
5. Insert the PC-Doctor CD into the internal optical drive. 6. Press cursor keys to select ATAPI CDx (x: 0, 1, ...) and then press Enter. 7. Follow the instructions on the screen. 8. The main panel of PC-Doctor appears. 9.
While the Windows operating system is running, press the ThinkVantage button. To start this program, do the following: • Click Start ➙ Control Panel ➙ System and Security ➙ Lenovo's System Health and Diagnostics. Windows Vista and Windows XP: Click Start ➙ All Programs ➙ ThinkVantage ➙ Lenovo ThinkVantage Toolbox Follow the instructions on the screen.
Page 38
For additional information about this program, see the Help for the program. ThinkPad T420 and T420i Hardware Maintenance Manual...
FRU tests The following table shows the test for each FRU. Table 1. FRU tests Applicable test System board 1. Diagnostics ➙ CPU/Coprocessor 2. Diagnostics ➙ Systemboard 3. If the docking station or the port replicator is attached to the ThinkPad Notebook, detach it.
Page 40
Table 1. FRU tests (continued) Applicable test TrackPoint or pointing If the TrackPoint does not work, check the configuration as specified in the ThinkPad device Setup Utility. If the TrackPoint is disabled, select Automatic to enable it. After you use the TrackPoint, the pointer may drift on the screen for a short time. This drift can occur when a slight, steady pressure is applied to the TrackPoint pointer.
Power system checkout To verify a symptom, do the following: 1. Turn off the computer. 2. Remove the battery pack. 3. Connect the ac power adapter. 4. Check that power is supplied when you turn on the computer. 5. Turn off the computer. 6.
Perform operational charging. If the battery status indicator or icon does not turn on, remove the battery pack and let it return to room temperature. Reinstall the battery pack. If the charge indicator or icon still does not turn on, replace the battery pack. If the charge indicator still does not turn on, replace the system board.
Page 43
Wire Voltage (V dc) +2.5 to +3.2 Black Ground • If the voltage is correct, replace the system board. • If the voltage is not correct, replace the backup battery. • If the backup battery discharges quickly after replacement, replace the system board. Chapter 3 General checkout...
Page 44
ThinkPad T420 and T420i Hardware Maintenance Manual...
2. Insert the Operating System Recovery Disc into the DVD drive. 3. Press F10 to save the Setup Utility configuration changes. Follow the instructions on the screen to begin the recovery process. 4. Select your language and click Next. 5. Read the license. If you agree with the terms and conditions, select I accept these terms and conditions and then click Next.
Attention: If the user HDP has been forgotten, check whether a master HDP has been set. If it has, it can be used for access to the hard disk drive. If no master HDP is available, neither Lenovo nor Lenovo authorized service technicians provide any services to reset either the user or the master HDP, or to recover data from the hard disk drive.
Page 48
3. Select Security, using the cursor directional keys to move the menu. 4. Select Password. 5. Select Hard-disk x password, where x is the letter of the hard disk drive. A pop-up window opens. 6. Select Master HDP. 7. Type the current master HDP in the Enter Current Password field. then leave the Enter New Password field blank, and press Enter twice.
Power management To reduce power consumption, the computer has three power management modes: screen blank, sleep (standby in Windows XP), and hibernation. Screen blank mode If the time set on the “Turn off monitor” timer in the operating system expires, the LCD backlight turns off. To put the computer into screen blank mode, do as follows: 1.
Hibernation mode In hibernation mode, the following occurs: • The system status, RAM, VRAM, and setup data are stored on the hard disk. • The system is powered off. Note: If the computer enters the hibernation mode while it is docked to the docking station, do not undock it before resuming normal operation.
Symptom-to-FRU index This section contains following information: • “Numeric error codes” on page 45 • “Error messages” on page 47 • “Beep symptoms” on page 48 • “No-beep symptoms” on page 48 • “LCD-related symptoms” on page 49 • “Intermittent problems” on page 50 •...
Table 2. Numeric error codes (continued) FRU or action, in sequence Symptom or error 0191 1. Run ThinkPad Setup Utility, and then save current System Security—Invalid Remote Change requested. setting by pressing F10. 2. System board. 0199 1. Run ThinkPad Setup Utility, and then save the System Security—...
Thermal sensing error. System board. This system does not support batteries that are not Replace the battery. genuine Lenovo-made or authorized. This system will continue to boot, but may not charge unauthorized batteries. Attention: Lenovo has no responsibility for the...
Beep symptoms Table 4. Beep symptoms Symptom or error FRU or action, in sequence One beep and a blank, unreadable, or flashing LCD. 1. Reseat the LCD connector. 2. LCD assembly. 3. External CRT. 4. System board. One long and two short beeps, and a blank or unreadable 1.
If the LCD you are servicing has two or less visible defective pixels, it should not be considered faulty. However, if the LCD has three or more visible defective pixels, it will be deemed as defective by Lenovo and it should be replaced.
Intermittent problems Intermittent system hang problems can be due to a variety of causes that have nothing to do with a hardware defect, such as cosmic radiation, electrostatic discharge, or software errors. FRU replacement should be considered only when a problem recurs. When analyzing an intermittent problem, do the following: 1.
Page 58
Table 7. Status indicators Indicator Meaning Speaker mute Orange: The speaker is on mute. To set the speakers on mute or unmute, press the speaker mute button. Microphone mute Orange: The microphone is on mute. None of the recording devices is available while the microphone mute is on by default.
Page 59
Table 7. Status indicators (continued) Indicator Meaning Power on Green: The computer is on and ready to use. This indicator stays lit around the power-on button whenever the computer is on and is not in sleep (standby) mode. Note: This indicator blinks when the computer is in sleep mode. Numeric lock (On-screen By default, when the numeric lock is on, the numeric lock indicator is indicator)
Page 60
Table 7. Status indicators (continued) Indicator Meaning Battery status Green: The battery charge level is 20% or higher. Orange: The battery charge level is between 5% and 20%. Fast blinking orange: The battery charge level is lower than 5% . Slow blinking orange: The battery is being charged.
Page 62
Table 8. Fn key combinations (continued) Key combination Description Fn+F7 Apply a presentation scheme directly, with no need to start Presentation Director. To disable this function and use the Fn+F7 key combination for switching a display output location, start Presentation Director, and change the settings. Note: If the computer is an Windows 7 model, it does not support presentation schemes, however the Fn+F7 combination might still be used to switch display output location.
Page 63
Table 8. Fn key combinations (continued) Key combination Description Fn+Home The computer display becomes brighter. The purpose of this method is to change the brightness level temporarily. On Windows Vista, the default brightness level is loaded after sleep (standby), hibernation, reboot, or detaching or attaching an ac power adapter.
Page 64
ThinkPad T420 and T420i Hardware Maintenance Manual...
If you replace the system board, you must restore the serial number of the system unit to its original value. Before replacing the system board, save the original serial number by doing the following: 1. Install the LENOVO ThinkPad Hardware Maintenance Diskette Version 1.76 or later, and restart the computer.
When you replace the system board, you must set the UUID on the new system board as follows: 1. Install the LENOVO ThinkPad Hardware Maintenance Diskette Version 1.76 or later, and restart the computer. 2. From the main menu, select 4. Assign UUID. A new UUID is created and written. If a valid UUID already exists, it is not overwritten.
Page 68
ThinkPad T420 and T420i Hardware Maintenance Manual...
Before servicing ThinkPad T420 and T420i Some models of the ThinkPad T420 and T420i you are servicing might have the SIM card that the customer has installed. If the computer you are servicing has the SIM card, remove it before you start the servicing. To remove the SIM card, you need to remove the battery pack first.
The only exception to this is if the battery pack is physically damaged or a customer is reporting a possible safety issue. If Lenovo ThinkVantage Toolbox is not installed in the computer, the customer should download this program before a non-physically damaged battery pack is replaced. Note that a physically damaged battery pack isa non-warranty replacement part.
1020 ExpressCard blank bezel Table 10. Removal steps of ExpressCard blank bezel When you press the ExpressCard blank bezel , it pops out When installing: Make sure that the bezel is correctly oriented as shown in the following figure. ThinkPad T420 and T420i Hardware Maintenance Manual...
1030 Serial Ultrabay Enhanced device or travel bezel For access, remove this FRU: • “1010 Battery pack” on page 65 Table 11. Removal steps of Serial Ultrabay Enhanced device or travel bezel Holding the bay lock latch in the unlocked position , slide the bay eject latch in the direction shown by arrow , and then pull out the Serial Ultrabay Enhanced device or the travel bezel in the direction shown by arrow to completely remove it...
1040 Hard disk drive (HDD) and solid state drive (SSD) For access, remove this FRU: • “1010 Battery pack” on page 65 Attention: • Do not drop the drive or apply any physical shock to it. The drive is sensitive to physical shock. Improper handling can cause damage and permanent loss of data.
Page 75
Table 12. Removal steps of hard disk drive and solid state drive (continued) For HDD and HDD rubber rails (9.5mm): For HDD and HDD rubber rails (7.0mm) : Chapter 8 Removing and replacing a FRU...
Page 76
Table 12. Removal steps of hard disk drive and solid state drive (continued) For SSD and spacers: When installing: Make sure that SSD spacers or HDD rubber rails are attached firmly. ThinkPad T420 and T420i Hardware Maintenance Manual...
1050 DIMM slot cover For access, remove this FRU: • “1010 Battery pack” on page 65 Table 13. Removal steps of DIMM slot cover Note: Loosen the screw , but do not remove it. Chapter 8 Removing and replacing a FRU...
1060 DIMM (in the slot on the underside of the computer) For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1050 DIMM slot cover” on page 71 Note: Your computer has two DIMM slots: one under the keyboard and another on the underside of the computer.
1070 PCI Express Mini Card for wireless WAN For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1050 DIMM slot cover” on page 71 Table 15. Removal steps of PCI Express Mini Card for wireless WAN In step , unplug the jacks by using the removal tool antenna RF connector (P/N: 08K7159), or pick the connectors with your fingers and gently unplug them in the direction of the arrow.
Page 80
Table 15. Removal steps of PCI Express Mini Card for wireless WAN (continued) Note: Plug the yellow cable into the jack labeled MAIN, and the blue cable into the jack labeled AUX on the card. If the computer you are servicing is a wireless WAN-ready model and does not have a wireless WAN card, route the antenna cables and secure them with a tape as shown in the following figure.
1080 Keyboard For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1050 DIMM slot cover” on page 71 Table 16. Removal steps of keyboard Step Screw (quantity) Color Torque M2 × 10 mm, wafer-head, nylon-coated (1) Silver 0.181 Nm (1.85 kgfcm)
Page 82
Table 16. Removal steps of keyboard (continued) Lift the keyboard a little in the direction shown by arrow , and then detach the connector ThinkPad T420 and T420i Hardware Maintenance Manual...
Page 83
When installing the keyboard, do as follows: Table 17. Installation steps of keyboard 1. Attach the keyboard connector. 2. Attach the keyboard so that the keyboard edges are under the frame as shown in the following figure. Chapter 8 Removing and replacing a FRU...
Page 84
Table 17. Installation steps of keyboard (continued) 3. To make sure that the front edge of the keyboard is housed firmly, gently press the keys with your palms and slightly slide the keyboard toward you until it snaps into position. ThinkPad T420 and T420i Hardware Maintenance Manual...
Page 85
Table 17. Installation steps of keyboard (continued) 4. Make sure that the front edge of the keyboard is attached firmly. 5. Secure the keyboard by tightening the screws from the bottom side of the computer. Chapter 8 Removing and replacing a FRU...
1090 DIMM (in the slot under the keyboard) For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1050 DIMM slot cover” on page 71 • “1080 Keyboard” on page 75 Note: Your computer has two DIMM slots: one under the keyboard and another on the underside of the computer.
Page 87
Table 18. Removal steps of DIMM (in the slot under the keyboard) (continued) When installing: Insert the notched end of the DIMM into the socket. Press the DIMM firmly, and pivot it until it snaps into place. Make sure that it is firmly fixed in the slot and does not move easily. Chapter 8 Removing and replacing a FRU...
1100 Backup battery For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1050 DIMM slot cover” on page 71 • “1080 Keyboard” on page 75 Table 19. Removal steps of backup battery DANGER Use only the battery specified in the parts list for your computer. Any other battery could ignite or explode. ThinkPad T420 and T420i Hardware Maintenance Manual...
Page 89
Table 19. Removal steps of backup battery (continued) Cable routing: Attach the backup battery and route the cable as shown in the figure below and make sure that the battery connector is attached firmly. Chapter 8 Removing and replacing a FRU...
1110 PCI Express Mini Card for wireless LAN For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1050 DIMM slot cover” on page 71 • “1080 Keyboard” on page 75 Table 20. Removal steps of PCI Express Mini Card for wireless LAN In step , unplug the jacks by using the removal tool antenna RF connector (P/N: 08K7159), or pick the connectors with your fingers and gently unplug them in the direction of the arrow.
Page 91
Table 20. Removal steps of PCI Express Mini Card for wireless LAN (continued) When installing: • In models with a wireless LAN card that has two antenna connectors, plug the gray cable into the jack marked MAIN or M, and the black cable into the jack marked AUX or A on the card. If the computer you are servicing has three cables, put the white cable in the cable protection tube and secure it with a tape as shown in this figure.
1120 Keyboard bezel assembly, FPC cable, and Bluethooth daughter card (BDC-2.1) For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1020 ExpressCard blank bezel” on page 66 • “1050 DIMM slot cover” on page 71 •...
Page 93
Table 21. Removal steps of keyboard bezel assembly, FPC cable, and Bluetooth daughter card (continued) Torque Step Screw (quantity) Color M2 × 3 mm, wafer-head, nylon-coated (1) Black 0.181 Nm (1.85 kgfcm) Black 0.181 Nm Shoulder screw (2) (1.85 kgfcm) Chapter 8 Removing and replacing a FRU...
Page 94
Table 21. Removal steps of keyboard bezel assembly, FPC cable, and Bluetooth daughter card (continued) When installing: Make sure that the connector is attached firmly. ThinkPad T420 and T420i Hardware Maintenance Manual...
Page 95
Table 21. Removal steps of keyboard bezel assembly, FPC cable, and Bluetooth daughter card (continued) When installing: Make sure that the connectors are attached firmly. Step Screw (quantity) Color Torque M2 × 3 mm, wafer-head, nylon-coated (1) Black 0.181 Nm (1.85 kgfcm) Chapter 8 Removing and replacing a FRU...
Page 96
Table 21. Removal steps of keyboard bezel assembly, FPC cable, and Bluetooth daughter card (continued) When installing: Make sure that the connector is attached firmly. ThinkPad T420 and T420i Hardware Maintenance Manual...
1130 SmartCard or Contactless SmartCard For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1050 DIMM slot cover” on page 71 • “1080 Keyboard” on page 75 • “1120 Keyboard bezel assembly, FPC cable, and Bluethooth daughter card (BDC-2.1)” on page 86 Table 22.
Page 98
Table 22. Removal steps of SmartCard or Contactless SmartCard (continued) When installing: Make sure that the connector is attached firmly. Table 23. Removal steps of SmartCard dummy spacer Some models have a SmartCard dummy spacer as a miscellaneous part. For those models, remove the spacer as shown: Step Screw (quantity)
1150 Speaker assembly For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1050 DIMM slot cover” on page 71 • “1080 Keyboard” on page 75 • “1120 Keyboard bezel assembly, FPC cable, and Bluethooth daughter card (BDC-2.1)” on page 86 Table 25.
Page 101
Table 25. Removal steps of speaker assembly (continued) When installing: Attach the speaker assembly and route the cable as shown in the following figure, and make sure that the speaker connector is attached firmly. Chapter 8 Removing and replacing a FRU...
1160 LCD unit For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1020 ExpressCard blank bezel” on page 66 • “1050 DIMM slot cover” on page 71 • “1070 PCI Express Mini Card for wireless WAN” on page 73 •...
Page 103
Table 26. Removal steps of LCD unit (continued) Torque Step Screw (quantity) Color M2 × 3 mm, wafer-head, nylon-coated (1) Black 0.181 Nm (1.85 kgfcm) Chapter 8 Removing and replacing a FRU...
Page 104
Table 26. Removal steps of LCD unit (continued) Torque Step Screw (quantity) Color M2.5 × 6 mm, wafer-head, nylon-coated (2) Black 0.392 Nm (4.0 kgfcm) ThinkPad T420 and T420i Hardware Maintenance Manual...
Page 105
Table 26. Removal steps of LCD unit (continued) When installing: • Make sure that you attach the connectors firmly. • Make sure that you route the cables correctly and you tape up in the proper positions as shown in the above figure. •...
Page 106
Table 26. Removal steps of LCD unit (continued) ThinkPad T420 and T420i Hardware Maintenance Manual...
1170 Fan assembly For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1020 ExpressCard blank bezel” on page 66 • “1050 DIMM slot cover” on page 71 • “1070 PCI Express Mini Card for wireless WAN” on page 73 •...
Page 108
Table 27. Removal steps of fan assembly (continued) For Integreted Graphics models: Step Screw (quantity) Color Torque Capture shoulder screw (4) Silver 0.181 Nm (1.85 kgfcm) black 0.181 Nm M2 × 3 mm, wafer-head, nylon-coated (1) (1.85 kgfcm) ThinkPad T420 and T420i Hardware Maintenance Manual...
Page 109
Table 27. Removal steps of fan assembly (continued) For Discrete Graphics models: For Integreted Graphics models: Chapter 8 Removing and replacing a FRU...
Page 110
Table 27. Removal steps of fan assembly (continued) When installing: • Before you attach the fan assembly to the computer, apply thermal grease, at an amount of 0.2 grams, on the parts marked as in the following figures. Either too much or too less application of grease can cause a thermal problem due to imperfect contact with a component.
Page 111
Table 27. Removal steps of fan assembly (continued) • When attaching the fan assembly to the frame, take care not to damage the heat sink of the fan assembly. • Make sure that the fan connector is attached firmly. Chapter 8 Removing and replacing a FRU...
1180 CPU For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1020 ExpressCard blank bezel” on page 66 • “1050 DIMM slot cover” on page 71 • “1070 PCI Express Mini Card for wireless WAN” on page 73 •...
1190 Base cover assembly and DC-in connector cable For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1020 ExpressCard blank bezel” on page 66 • “1030 Serial Ultrabay Enhanced device or travel bezel” on page 67 •...
Table 29. Removal steps of base cover assembly and DC-in connector cable (continued) Torque Step Screw (quantity) Color M2 × 5 mm, wafer-head, nylon-coated (8) Black 0.181 Nm (1.85 kgfcm) When installing: Make sure that the connector is attached firmly. When installing: Make sure that the wireless switch is adjusted as shown in callout ThinkPad T420 and T420i Hardware Maintenance Manual...
Page 115
Table 29. Removal steps of base cover assembly and DC-in connector cable (continued) Step Screw (quantity) Color Torque Black 0.181 Nm M2 × 3 mm, wafer-head, nylon-coated (1) (1.85 kgfcm) Chapter 8 Removing and replacing a FRU...
Page 116
Table 29. Removal steps of base cover assembly and DC-in connector cable (continued) Note: Applying labels to the base cover The new base cover FRU is shipped with a kit containing labels of several kinds. When you replace the base cover, you need to apply the following label: Homologation label The following labels need to be peeled off from the old base cover, and need to be put on the new base cover.
Page 117
For the location of each label, refer the following figure: Chapter 8 Removing and replacing a FRU...
1200 Magnesium structure frame For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1020 ExpressCard blank bezel” on page 66 • “1030 Serial Ultrabay Enhanced device or travel bezel” on page 67 • “1040 Hard disk drive (HDD) and solid state drive (SSD)” on page 68 •...
1210 System board and ExpressCard slot assembly For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1020 ExpressCard blank bezel” on page 66 • “1030 Serial Ultrabay Enhanced device or travel bezel” on page 67 •...
Page 121
Table 31. Removal steps of system board and ExpressCard slot assembly (continued) Accelerometer chip for the HDD Active Protection System Platform Controller Hub (PCH) Graphic Processing Unit (GPU) (Discrete graphics chip) Note: The GPU is only for models with switchable graphics. Models with integrated graphics do not have a GPU on the system board.
Table 31. Removal steps of system board and ExpressCard slot assembly (continued) Torque Step Screw (quantity) Color M2 × 3 mm, wafer-head, nylon-coated (1) Black 0.181 Nm (1.85 kgfcm) When installing: Make sure that the connector is attached firmly. ThinkPad T420 and T420i Hardware Maintenance Manual...
2010 LCD bezel assembly For access, remove the following FRU: • “1010 Battery pack” on page 65 Table 32. Removal steps of LCD bezel assembly Chapter 8 Removing and replacing a FRU...
2020 LED board For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “2010 LCD bezel assembly” on page 117 Table 33. Removal steps of LED board Step Screw (quantity) Color Torque 0.181 Nm M2 × 3 mm, flat-head, nylon-coated (1) Silver (1.85 kgfcm) ThinkPad T420 and T420i Hardware Maintenance Manual...
Page 125
Table 33. Removal steps of LED board (continued) When installing: Make sure that the connector is attached firmly. Chapter 8 Removing and replacing a FRU...
2030 Integrated camera For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “2010 LCD bezel assembly” on page 117 Table 34. Removal steps of integrated camera Torque Step Screw (quantity) Color M2 × 3 mm, flat-head, nylon-coated (1) Black 0.181 Nm (1.85 kgfcm)
Page 127
Table 34. Removal steps of integrated camera (continued) Chapter 8 Removing and replacing a FRU...
2040 LCD panel and LCD cable For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1020 ExpressCard blank bezel” on page 66 • “1050 DIMM slot cover” on page 71 • “1070 PCI Express Mini Card for wireless WAN” on page 73 •...
Page 129
Table 35. Removal steps of LCD panel and LCD cable (continued) When installing: When attaching the LCD panel to the cover, gently press the left and right edges covered with metal. DO not press the surface of the panel or apply any excessive force to the panel. When installing: Make sure that the connector is attached firmly.
2050 Camera cable For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1020 ExpressCard blank bezel” on page 66 • “1050 DIMM slot cover” on page 71 • “1070 PCI Express Mini Card for wireless WAN” on page 73 •...
2070 Hinges and LCD rear cover assembly For access, remove these FRUs in order: • “1010 Battery pack” on page 65 • “1020 ExpressCard blank bezel” on page 66 • “1050 DIMM slot cover” on page 71 • “1070 PCI Express Mini Card for wireless WAN” on page 73 •...
Page 134
Table 38. Removal steps of hinges and LCD rear cover assembly (continued) ThinkPad T420 and T420i Hardware Maintenance Manual...
Rear view Status indicators Note: For the description of each indicator, see Chapter 5 “Status indicators” on page 51. SmartCard slot DisplayPort connector USB connector RJ-45 (Ethernet) connector External monitor connector Power jack USB connector Modem connector or IEEE 1394 Chapter 9 Locations...
Table 39. Parts list—Overall (continued) No. FRU (Overall) FRU no. CRU ID — Thermal grease 91P8835 — ac power adapter (see “Information about ac power adapters” on page 170.) LCD FRUs In ThinkPad T420 and T420i, there are following types of LCDs. •...
Page 161
Table 40. Parts list—14.0-inch HD (1366 x 768) LED Backlight Anti-Glare Display No. FRU (14.0-inch HD (1366 x 768) LED backlight Anti-Glare Display) FRU no. See “Miscellaneous parts” on page 167. Chapter 10 Parts list...
Page 162
Table 40. Parts list—14.0-inch HD (1366 x 768) LED Backlight Anti-Glare Display (continued) No. FRU (14.0-inch HD (1366 x 768) LED backlight Anti-Glare Display) FRU no. 04W1609 N LCD bezel assembly • 4177–CTO, 22x, 23x, 24x, 25x, 26x, 27x, 28x, 29x, 2Ax, 2Bx, 2Cx, 2Dx, 2Ex, 2Fx, 2Gx, 2Hx, 2Jx, 2Kx, 2Lx, 2Mx, 2Nx, 2Px, Q2x, Q3x, Q4x, Q5x, Q7x, Q8x, QAx, QBx, QCx, QDx •...
Page 163
Table 40. Parts list—14.0-inch HD (1366 x 768) LED Backlight Anti-Glare Display (continued) No. FRU (14.0-inch HD (1366 x 768) LED backlight Anti-Glare Display) FRU no. 93P5687 LCD module, 14.0-inch HD (1366 x 768) LED backlight Anti-Glare Display • 4177–CTO, 22x, 23x, 24x, 25x, 26x, 27x, 28x, 29x, 2Ax, 2Bx, 2Cx, 2Dx, 2Ex, 2Fx, 2Gx, 2Hx, 2Jx, 2Mx, Q4x, Q5x, Q7x, QCx, QDx, QEx •...
Page 164
Table 40. Parts list—14.0-inch HD (1366 x 768) LED Backlight Anti-Glare Display (continued) No. FRU (14.0-inch HD (1366 x 768) LED backlight Anti-Glare Display) FRU no. Hinges 04W1610 N • 4177–CTO, 22x, 23x, 24x, 25x, 26x, 27x, 28x, 29x, 2Ax, 2Bx, 2Cx, 2Dx, 2Ex, 2Fx, 2Gx, 2Hx, 2Jx, 2Kx, 2Lx, 2Mx, 2Nx, 2Px, Q2x, Q3x, Q4x, Q5x, Q7x, Q8x, QAx, QBx, QCx, QDx •...
Page 165
Table 40. Parts list—14.0-inch HD (1366 x 768) LED Backlight Anti-Glare Display (continued) No. FRU (14.0-inch HD (1366 x 768) LED backlight Anti-Glare Display) FRU no. 04W1615 N Wireless antenna (wireless LAN/wirless WAN) • 4177–CTO, 22x, 23x, 24x, 25x, 26x, 27x, 28x, 29x, 2Ax, 2Bx, 2Cx, 2Dx, 2Ex, 2Fx, 2Gx, 2Hx, 2Jx, 2Kx, 2Lx, 2Mx, 2Nx, 2Px, Q2x, Q3x, Q4x, Q5x, Q7x, Q8x, QAx, QBx, QCx, QDx •...
Page 166
Table 40. Parts list—14.0-inch HD (1366 x 768) LED Backlight Anti-Glare Display (continued) No. FRU (14.0-inch HD (1366 x 768) LED backlight Anti-Glare Display) FRU no. LED cable 04W1619 N • 4177–CTO, 22x, 23x, 24x, 25x, 26x, 27x, 28x, 29x, 2Ax, 2Bx, 2Cx, 2Dx, 2Ex, 2Fx, 2Gx, 2Hx, 2Jx, 2Kx, 2Lx, 2Mx, 2Nx, 2Px, Q2x, Q3x, Q4x, Q5x, Q7x, Q8x, QAx, QBx, QCx, QDx •...
Page 167
Table 40. Parts list—14.0-inch HD (1366 x 768) LED Backlight Anti-Glare Display (continued) No. FRU (14.0-inch HD (1366 x 768) LED backlight Anti-Glare Display) FRU no. 04W1620 N Clear plate kit • 4177–CTO, 22x, 23x, 24x, 25x, 26x, 27x, 28x, 29x, 2Ax, 2Bx, 2Cx, 2Dx, 2Ex, 2Fx, 2Gx, 2Hx, 2Jx, 2Kx, 2Lx, 2Mx, 2Nx, 2Px, Q2x, Q3x, Q4x, Q5x, Q7x, Q8x, QAx, QBx, QCx, QDx •...
Page 168
Table 41. Parts list—14.0-inch HD+ (1600 x 900) LED backlight Anti-Glare Display (continued) No. FRU (14.0-inch HD+ (1600 x 900) LED backlight Anti-Glare Display) FRU no. 04W1613 N Camera module (No camera and with microphone) • 4177–CTO, Q7x, QCx • 4178–CTO •...
Miscellaneous parts Table 43. Parts list—Miscellaneous parts FRU no. Screw kit: 04W1605 • M2 × 3 mm, black (50) • M2 × 5 mm, black (20) • M2 × 8 mm, black (15) • M2 × 10 mm, Silver (4) •...
Page 174
Table 43. Parts list—Miscellaneous parts (continued) FRU no. Keyboard bezel miscellaneous parts: 04W1603 • Magnet - suspend switch • Bracket - touchpad • Bracket - right speaker • Bracket - left speaker • Bracket - left speaker EMI spring • Bracket - FPR EMI •...
Page 175
• Shield - EMC • Clear plate - LCD rear cover • LED lens - LCD rear cover • ThinkPad logo • Lenovo logo • LCD latch - right • LCD latch - left • Sponge - center • Sponge - upper •...
Power cords A ThinkPad power cord for a specific country or region is usually available only in that country or region: Table 46. Parts list—2-pin power cords Country or region FRU no. Argentina 42T5020 42T5105 • models -CTO, xxY Brazil 42T5180 42T5183 •...
Windows 7 Professional (64 bit) DVDs Windows 7 Professional (64 bit) is preinstalled as the operating system in the following models: • 4177-CTO, 2Px, 2Nx, 2Kx, QBx, Q8x, Q5x, 2Cx, 27x, Q4x, Q3x, Q2x, 25x, 2Dx, QCx, 2Bx, 2Ax, 29x, 28x, 26x, QEx •...
Windows 7 Home Basic (32 bit) DVDs Windows 7 Home Basic (32 bit) is preinstalled as the operating system in the following models: • 4177-CTO, 2Ex, 24x, 23x, 22x • 4178-CTO, 9Ex, 9Dx • 4179-CTO, G9x, G8x • 4180-CTO, MGx, MAx •...
Windows 7 Home Premium (32 bit) DVDs Windows 7 Home Premium (32 bit) is preinstalled as the operating system in the following models: • 4177-CTO • 4178-CTO • 4179-CTO, G4x • 4180-CTO, LNx • 4236-CTO, NCx Table 51. Parts list—Windows 7 Home Premium (64 bit) recovery DVDs Language Simplified Chinese 03W7946...
Windows 7 Home Premium (64 bit) DVDs Windows 7 Home Premium (64 bit) is preinstalled as the operating system in the following models: • 4177-CTO, 2Mx, 2Lx, 2Jx, QFx • 4178-CTO, 9Nx, 9Fx • 4179-CTO • 4180-CTO • 4236-CTO, NRx, NQx, NPx Table 52.
USB floppy diskette drive tool kit 27L3452 Test card for integrated Smart Card 42W7820 — LENOVO ThinkPad Hardware Maintenance Diskette Version 1.76 or later Note: Download the file from the following Web site: http://www.lenovo.com/spm ThinkPad T420 and T420i Hardware Maintenance Manual...
Lenovo representative for information on the products and services currently available in your area. Any reference to a Lenovo product, program, or service is not intended to state or imply that only that Lenovo product, program, or service may be used. Any functionally equivalent product, program, or service that does not infringe any Lenovo intellectual property right may be used instead.
Trademarks The following terms are trademarks of Lenovo in the United States, other countries or both: Active Protection System Lenovo Rescue and Recovery ThinkLight ThinkPad ThinkVantage TrackPoint Ultrabay IBM (used under license) is trademark of the International Business Machines Corporation in the United...
Page 188
Part Number: 0A60007 Printed in China (1P) P/N: 0A60007 *0A60007*...
Need help?
Do you have a question about the ThinkPad T420 2620 and is the answer not in the manual?
Questions and answers