Lenovo ThinkPad T420s Hardware Maintenance Manual
Lenovo ThinkPad T420s Manual
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- Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 1
Hardware Maintenance Manual ThinkPad T420s and T420si - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 2
and the product it supports, be sure to read the general information under Appendix A "Notices" on page 143. Fifth Edition (March 2012) © Copyright Lenovo 2012. LIMITED AND RESTRICTED RIGHTS NOTICE: If data or software is delivered pursuant a General Services Administration "GSA" contract, use - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 3
for DOS diagnostics program 36 System supporting the Lenovo diagnostics programs 40 Power system checkout 42 Checking the ac power adapter 43 Checking operational charging 44 Checking the battery pack 44 Checking the backup battery 44 Chapter 4. Related service information 47 Restoring the - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 4
Bluetooth-wireless radio switch FPC . . . . 91 1150 System board, fan assembly, 34-mm ExpressCard reader, and base cover 93 1160 mSATA 99 2010 LCD bezel assembly 101 2020 LCD panel 102 2030 Integrated camera, microphone, or hall sensor card 104 2040 LED sub card power adapter 134 Power service - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 5
this manual This manual contains service and reference information for the following ThinkPad® products. ThinkPad T420s and T420si Machine types (MT) 4170, 4171, 4172, 4173, 4174, 4175, and 4176 Use this manual along with the advanced diagnostic tests to troubleshoot problems. Important: This manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 6
iv Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 7
with before you service a ThinkPad Notebook. • "General safety" on page 1 • "Electrical safety" on page 2 • "Safety inspection guide" on page 3 machine to the customer. • Fan louvers on the machine help to prevent overheating of internal components. Do not obstruct fan louvers or cover them with - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 8
test Instructions Power supply units - Pumps - Blowers and fans - Motor generators - Similar units to listed above This practice ensures correct grounding of the units. • If an electrical accident occurs: - Use caution; do not become a victim yourself. - Switch off power. 2 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 9
designed and built, required safety items were installed to protect users and service technicians from injury. This guide addresses only those items. You should use good judgment to identify potential safety hazards due to attachment of non-ThinkPad features or options not covered by this inspection - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 10
specific service requirement. Note: The use of a grounding system to guard against ESD damage is desirable but not necessary. - Attach the ESD ground clip to any frame ground, ground braid, or green-wire ground. - When working on a double-insulated or battery-operated system Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 11
DANGER DANGER DANGER DANGER DANGER Chapter 1. Safety information 5 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 12
DANGER DANGER DANGER 6 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 13
Chapter 1. Safety information 7 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 14
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PERIGO PERIGO PERIGO PERIGO PERIGO Chapter 1. Safety information 9 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 16
PERIGO PERIGO PERIGO 10 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 17
DANGER DANGER DANGER DANGER DANGER Chapter 1. Safety information 11 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 18
DANGER DANGER DANGER 12 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 19
VORSICHT VORSICHT VORSICHT VORSICHT VORSICHT Chapter 1. Safety information 13 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 20
VORSICHT VORSICHT VORSICHT 14 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 21
Chapter 1. Safety information 15 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 22
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statements in this section are provided in the following languages: • English • Arabic • Brazilian Portuguese • French • German • Hebrew • Japanese • Korean • Spanish • Traditional Chinese 24 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 31
Chapter 1. Safety information 25 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 32
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installed before replacing any FRUs listed in this manual. After a system board is replaced, ensure that the latest UEFI BIOS is loaded to the system board before completing the service action. To download software fixes, drivers, and UEFI BIOS, do as follows: 1. Go to http://www.lenovo.com/support - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 38
disk 1, and assigned drive D:. The mSATA drive is installed in the wireless WAN card slot of the computer. The Lenovo preloaded software is installed on the mSATA drive. Important notice for replacing a system board Some components mounted on a system board are very sensitive. Improper handling of - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 39
. An example of key commodities are hard disk drives, system boards, microprocessors, Liquid Crystal Displays (LCDs), and memory. • Remember, all CTO and Web site: http://www.lenovo.com/support • To view the key commodities, do the following: 1. Click Products & Service Warranty. 2. Click Check - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 40
Product & Parts Detail and then follow the instructions on the screen to reach the Product and Parts Details page. 2. Click the Parts Detail tab to view the list of service parts. Using the HMM For Key Commodities (Examples - hard disk drive, system board, microprocessor, LCD, and memory) Use the - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 41
guide" on page 36 - "System supporting the Lenovo ThinkVantage Toolbox program and the PC-Doctor for DOS diagnostics program" on page 36 - "System supporting the Lenovo diagnostics programs" on page 40 • "Power system checkout" on page 42 The descriptions in this chapter apply to any ThinkPad - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 42
as a guide in identifying and correcting problems with the ThinkPad notebook computers. 1. Identify the failing symptoms in as much detail as possible. 2. Verify the symptoms. Try to re-create the failure by running the diagnostic test or by repeating the operation. System supporting the Lenovo - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 43
docking station. To test a USB device, connect it to the USB connector of the computer. Testing the computer Note: The PC-Doctor for DOS CD-R/CD-RW disc supports only test of internal optical disc drives (CD-RW, CD-RW/DVD Combo, and DVD Multi drives) on ThinkPad computers. It does not support test - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 44
Mouse • Diskette • System Load • Optical Drive Test • Intel WLAN Radio Test Notes: • In the Keyboard test in Interactive Tests, the Fn key should be held down for at least 2 seconds; otherwise, it cannot be sensed. • Video Adapter test supports only the LCD display on the ThinkPad Notebook. If you - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 45
Tests • Benchmark System • DOS Shell • Tech Support Form • Battery Rundown • Erase Drive Contents • View PCDR Host Log Lenovo ThinkVantage Toolbox Lenovo To install the latest Lenovo ThinkVantage Toolbox on the computer, click Download Lenovo ThinkVantage Toolbox, and then follow the instructions on - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 46
Table 1. FRU tests FRU 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. Power Diagnostics ➙ ThinkPad Devices ➙ AC Adapter, Battery 1 (Battery 2). LCD - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 47
, see the help information system. Quick test programs Lenovo Hard Drive Quick Test and Lenovo Memory Quick Test are two quick test programs that enable you to troubleshoot and resolve computer internal storage and memory problems. Notes: • If the computer you are servicing is not installed with the - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 48
the computer you are servicing is not installed with the UEFI diagnostic program, you can download a bootable diagnostic program from the Lenovo Support Web site. The bootable diagnostic programs enable you to test computer memory and internal storage devices, view system information, and check and - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 49
different from the one you are servicing. 3. If the voltage is not correct, replace the ac power adapter. 4. If the voltage is acceptable, do the following: • Replace the system board. • If the problem persists and your system supports the PC doctor for DOS, go to "FRU tests" on page 39. Note: Noise - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 50
taskbar and wait for a moment (but do not click), and the percentage of battery power remaining is displayed. To get detailed information about the battery, double-click the Power Manager Battery Gauge icon. Note: If the battery pack becomes hot, it may not be able to charge. Remove it from the - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 51
the voltage of the backup battery. See the following figure. Wire Red Black Voltage (V dc) +2.5 to +3.2 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 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 52
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Power management" on page 50 • "Symptom-to-FRU index" on page 52 Service Web site: When the latest maintenance diskette and the system program service diskette become available, they will be posted on http://www.lenovo.com/support To install the screen is displayed. Follow the instructions on the - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 54
user instructions and the following set of DVDs to restore the computer to the original factory configuration. Operating System Recovery Disc (one disc) Applications and Drivers When the logo screen is displayed or if you hear repeating beeps, release the F1 key. The ThinkPad Setup program opens. b. - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 55
Note: After restoring a drive to the factory default settings, you might need to reinstall some device drivers. Passwords As many as three passwords may be needed for any ThinkPad Notebook: the power-on password, the hard disk password, and the supervisor password. If any of these passwords has been - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 56
, the password prompt does not appear. The power-on password has been removed. 5. Reinstall the backup battery and the battery pack. (B) If an supervisor password has been set and is known by the service technician: 1. Turn on the computer. 2. When the ThinkPad logo comes up, immediately press F1 to - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 57
time" has been set on the timer, and the user does not do any operation with the keyboard, the TrackPoint, the hard disk, the parallel connector, or the diskette drive within that time. • If the battery indicator blinks orange, indicating that the battery power is low. Note: Even if you do not set - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 58
. If no numeric code is displayed, check the narrative descriptions of symptoms. If the symptom is not described there, go to "Intermittent problems" on page 56. Note: For a device not supported by diagnostic codes in the ThinkPad Notebooks, see the manual for that device. 52 Hardware Maintenance - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 59
than 8 hours by connecting the ac power adapter. 2. Replace the backup battery and run ThinkPad Setupto reset the time and date. 1802 Unauthorized network card is plugged in-Turn off and remove the miniPCI network card. 1. Remove Mini PCI network card. 2. System board. 1820 More than one external - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 60
SATA device. 2. Mini SATA device. 3. System board. System board. System board. Error messages Table 3. Error messages Symptom or error Fan error. Thermal sensing error. This system does not support batteries that are not genuine Lenovo-made or authorized. The system will continue to boot, but may - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 61
If a mini-PCI Ethernet card is installed, confirm that Alert On LAN 2 in ThinkPad Setup is disabled. 1. DIMM. 2. System board Reinstall the operating system. System board (security chip) System board No-beep symptoms Table 5. No-beep symptoms Symptom or error No beep, power-on indicator on, LCD - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 62
the FRU shown by the FRU code. Rerun the test to verify that no more errors exist. Undetermined problems If the diagnostic tests did not identify the adapter or device that has failed, if wrong devices are installed, or if the system simply is not operating, follow these procedures to isolate - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 63
Chapter 5. Status indicators This chapter presents the system status indicators that show the status of the computer. 1 2 3 456 9 7 8 10 11 © Copyright Lenovo 2012 57 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 64
mode or turn off the computer. Note: Do not move the system while the green device access light is on. Sudden physical shock could cause drive errors. 7 Serial Ultrabay Slim device status Green: A Serial Ultrabay Slim device is installed and in use. Blinking A Serial Ultrabay Slim device is in - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 65
status indicator does not work while the computer is turned off or is in sleep (standby) mode or hibernation mode. An error occurred in the battery. The ac power adapter is attached to the computer. The battery pack of the computer is fully charged or detached. Chapter 5. Status indicators 59 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 66
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in IEEE standard 802.11, the following device drivers must be installed on the computer beforehand: • ThinkPad Power Management driver • OnScreen Display Utility • Wireless device drivers Fn+F6 Change the camera settings and the setting of the microphone mute button. When you press Fn+F6, the - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 68
to normal operation, press the power button for less than four seconds. Note: To use Fn+F12 for hibernation, you must have the ThinkPad PM device driver installed on the computer. Turn the ThinkLight® on or off. Note: This function is supported only on the ThinkPad Notebooks that have the ThinkLight - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 69
Lenovo installs an Optional-service CRU according to the warranty service for your product. Where you are installing the CRU, Lenovo will ship the CRU to you. CRU information and replacement instructions cause a reliability problem. In the ThinkPad notebook computer, this problem is addressed with - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 70
serial number by doing the following: 1. Install the LENOVO ThinkPad Hardware Maintenance Diskette Version 1.76 or later and restart the computer. 2. From the main menu, select 1. Set System Identification. 3. Select 1. Add S/N data from EEPROM. Follow the instructions on the screen. If the MTM and - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 71
year A.D. 3400. No two computers in the world have the same number. 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 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 72
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removing any FRU, turn off the computer, unplug all power cords from electrical outlets, remove the battery pack, and then disconnect any interconnecting cables. Attention: ESD) strap (P/N 6405959). Before servicing ThinkPad T420s and T420si models Removing the SIM card: © Copyright Lenovo 2012 67 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 74
of the ThinkPad T420s and T420si 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. (See 1010 Battery pack.) After - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 75
not be replaced unless this diagnostic shows that the battery is defective. 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 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 76
drive (SSD) or hard disk drive (HDD) For access, remove the FRU: • "1010 Battery pack" on page 68 Attention: • Do not drop the drive or apply any physical shock to , have the user make a backup copy of all the information on it if possible. • Never remove the drive while the system is operating or - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 77
Removal steps of SSD or HDD 1 2 Step 1 Screw (quantity) M3 × 3 mm, flat-head, nylon-coated (1) Color Black Torque 0.181 Nm (1.85 kgfcm) When installing: Make sure that the SSD or HDD is firmly attached. 4 Chapter 8. Removing and replacing a FRU 71 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 78
For HDD and HDD rubber rails: 5 5 For SSD and SSD spacers: 5 5 1040 DIMM For access, remove this FRU: • "1010 Battery pack" on page 68 Removal steps of DIMM Note: Remove the screws 1 . 72 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 79
1 Step 1 Screw (quantity) M2 × 5 mm, flat-head, nylon-coated (2) Color Black Torque 0.181 Nm (1.85 kgfcm) Chapter 8. Removing and replacing a FRU 73 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 80
installing: Insert the notched end of the DIMM into the socket. Press the DIMM in firmly, and pivot it until it snaps into place. Make sure that it is firmly attached in the slot and does not move easily. 1050 PCI Express Mini Card for wireless LAN For access, remove this FRU: • "1010 Battery - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 81
1 Step 1 Screw (quantity) M2 × 5 mm, flat-head, nylon-coated (2) Color Black Torque 0.181 Nm (1.85 kgfcm) Note: Some models might have only two antenna cables. Chapter 8. Removing and replacing a FRU 75 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 82
4 3 Step 4 Screw (quantity) M2 × 3 mm, small-head, nylon-coated (1) Color Silver Torque 0.181 Nm (1.85 kgfcm) 76 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 83
5 When installing: • In models with a wireless LAN card that has two antenna connectors, plug the gray cable into the jack labeled MAIN or M, and the black cable into the jack labeled AUX or A on the card. If the computer you are servicing has three cables, put the white cable in the cable - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 84
1 Step 1 Screw (quantity) M2 × 5 mm, flat-head, nylon-coated (2) Color Black Torque 0.181 Nm (1.85 kgfcm) 78 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 85
Color Silver Torque 0.181 Nm (1.85 kgfcm) 5 When installing: Plug the orange cable into the jack labeled MAIN, and the blue cable into the jack labeled AUX on the card. 1070 4-in-1 media card reader For access, remove this FRU: • "1010 Battery pack" on page 68 Chapter 8. Removing and replacing - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 86
steps of 4-in-1 media card reader 1 2 1080 Keyboard For access, remove this FRU: • "1010 Battery pack" on page 68 Removal steps of keyboard Note: Remove the screws 1 . 1 Step 1 Screw (quantity) M2 × 5 mm, flat-head, nylon-coated (2) 80 Hardware Maintenance Manual Color Black Torque 0.181 Nm - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 87
2 2 Step 2 Screw (quantity) M2 × 5 mm, flat-head, nylon-coated (2) Color Black Torque 0.181 Nm (1.85 kgfcm) Slightly press the keyboard and slide it a little bit forward, in the direction shown by arrow 3 , to detach the front edge of the keyboard from the frame. Then, lift up the keyboard in - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 88
5 6 Installation steps of keyboard When installing the keyboard, do the following: 1. Attach the keyboard connector. 82 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 89
the keyboard toward you until it snaps into position. 4. Secure the keyboard by tightening the screws from the bottom side of the computer. 1090 Backup battery For access, remove these FRUs in order: • "1010 Battery pack" on page 68 Chapter 8. Removing and replacing a FRU 83 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 90
or explode. Removal steps of backup battery 1 2 When installing: Attach the backup battery a in the insulation sheet as shown in the figure below and make sure that the battery connector is attached firmly. a 1100 Palm rest with fingerprint reader, smart card reader, and speaker For access, remove - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 91
Note: In models with the fingerprint reader, the sensor is attached to the palm rest FRU. If the fingerprint reader is defective, you can replace the palm rest by following the procedures in this section. The replacement procedures are the same for a palm rest with or without a fingerprint reader. - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 92
6 6 5 55 6 6 5 7 86 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 93
12 8 10 9 11 132 132 13 Removal steps of smart card reader 1 1 1 1 1 Step 1 Screw (quantity) M2 × 3 mm, flat-head, nylon-coated (5) Color Silver Torque 0.181 Nm (1.85 kgfcm) Chapter 8. Removing and replacing a FRU 87 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 94
flat-head, nylon-coated (4) Color Silver Torque 0.181 Nm (1.85 kgfcm) 1110 LCD unit For access, remove these FRUs in order: • "1010 Battery pack" on page 68 • "1080 Keyboard" on page 80 • "1100 Palm rest with fingerprint reader, smart card reader, and speaker" on page 84 88 Hardware Maintenance - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 95
Removal steps of LCD unit 1 Step 1 Screw cap 1 Screw (quantity) M2.5 × 5 mm, flat-head, nylon-coated (2) Color Black Torque 0.392 Nm (4.0 kgfcm) 3 2 Chapter 8. Removing and replacing a FRU 89 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 96
are not subjected to any tension. Tension could cause the cables to be damaged by the cable guides, or a wire to be broken. 1120 DC-in sub card For access, remove these FRUs in order: • "1010 Battery pack" on page 68 • "1080 Keyboard" on page 80 • "1100 Palm rest with fingerprint reader, smart - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 97
Color Silver Torque 0.181 Nm (1.85 kgfcm) 1130 Bluetooth daughter card (BDC-3.0) • "1010 Battery pack" on page 68 • "1030 Solid state drive installing: Make sure that the connector is attached firmly. 1140 Bluetooth-wireless radio switch FPC For access, remove these FRUs in order: • "1010 Battery - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 98
LCD unit" on page 88 • "1130 Bluetooth daughter card (BDC-3.0)" on page 91 Removal steps of Bluetooth-wireless radio switch FPC 1 2 3 5 4 Step 3 Screw (quantity) M2 × 3 mm, bind-head, nylon-coated (1) Color Silver When installing: Attach the wireless radio switch as shown in the following - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 99
system supports PC-Doctor for DOS, after replacing the system board, run PC-Doctor for DOS to make sure that HDD Active Protection system still functions. The procedure is as follows: 1. Place the computer on a horizontal surface. 2. Run Diagnostics ➙ ThinkPad Devices ➙ HDD Active Protection Test - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 100
on page 80 • "1100 Palm rest with fingerprint reader, smart card reader, and speaker" on page 84 • "1110 LCD unit" on page 88 • "1120 DC-in sub card" on page 90 • "1140 Bluetooth-wireless radio switch FPC" on page 91 System board, fan assembly, 34-mm ExpressCard reader, and base cover The following - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 101
1 2 3 Step 1 2 Screw (quantity) M 2 × 9 mm, flat head, nylon-coated (1) M2 × 3 mm, flat head, nylon-coated (1) 4 4 4 4 Color Black Silver Torque 0.181 Nm (1.85 kgfcm) 0.181 Nm (1.85 kgfcm) Step 4 Screw (quantity) M2 × 5 mm, big-head, nylon-coated (4) Color Black Torque 0.181 Nm (1.85 kgfcm) - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 102
base cover assembly. Turn the system board over, and then disconnect the fan assembly from the system board. 7 6 8 Step 7 Screw (quantity) M2 × 5 mm, big-head, nylon-coated (4) Color Black Torque 0.181 Nm (1.85 kgfcm) When installing: • Before you attach the fan assembly to the computer, apply - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 103
a b • Make sure that the fan connector is attached firmly. Remove the three screws and then remove the 34-mm ExpressCard reader from the system board. 9 9 9 Step 9 Screw (quantity) M2 × 3 mm, flat-head, nylon-coated (3) Color Silver Torque 0.181 Nm (1.85 kgfcm) 10 Chapter 8. Removing and - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 104
a letter to the customer stating what the label was originally on the system and what the label part number, serial number, and product key were. on the new base cover. 1 SIM ICCID label 2 Brazil wireless card label 3 Brazil WWAN label 4 Brazil Bluetooth label 5 SIRIM label or Indornesia - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 105
the new base cover. 1160 mSATA For access, remove this FRU: • "1010 Battery pack" on page 68 Attention: • Do not drop the drive or apply any removing the drive, have the user make a backup copy of all the information on it if possible. • Never remove the drive while the system is operating or is in - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 106
3 4 Step 3 Screw (quantity) M2 × 3 mm, small-head, nylon-coated (1) Color Silver Torque 0.181 Nm (1.85 kgfcm) 100 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 107
5 2010 LCD bezel assembly For access, remove this FRU: • "1010 Battery pack" on page 68 Removal steps of LCD bezel assembly 1 1 Step 1 Screw cap Screw (quantity) Color M2 × 5 mm, shoulder-socket head, nylon-coated (2) Black Torque 0. - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 108
Battery pack" on page 68 • "2010 LCD bezel assembly" on page 101 The LCD panel and the peripheral parts used in this product are very sensitive. Improper handling of the LCD panel can cause damage to the parts, and may cause a system malfunction such as a missing dot, missing line, or pixel problems - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 109
not unplug the cable by pulling it. Applying tension to the cable could cause the cable to be damaged or a wire to be broken. When installing: • Place the LCD panel on a soft and clean sheet spread on a flat table, and plug the cable by pushing the left and right edges of - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 110
with metal. Do not press the surface of the panel or apply any excessive force to the panel. 2030 Integrated camera, microphone, or hall sensor card For access, remove these FRUs, in order: • "1010 Battery pack" on page 68 • "2010 LCD bezel assembly" on page 101 • "2020 LCD panel" on page 102 104 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 111
steps of integrated camera, microphone, or hall sensor card 4 1 3 2 Step 1 Screw (quantity) M2 × 3 mm, small-head, nylon-coated (1) Color Silver Torque 0.181 Nm (1.85 kgfcm) When installing: Make sure that the connector of the integrated camera, microphone, or the hall sensor card is attached - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 112
6 5 2040 LED sub card For access, remove these FRUs in order: • "1010 Battery pack" on page 68 • "2010 LCD bezel assembly" on page 101 • "2020 LCD panel" on page 102 106 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 113
page 80 • "1100 Palm rest with fingerprint reader, smart card reader, and speaker" on page 84 • "1110 LCD unit" on page 88 • "1120 DC-in sub card" on page 90 • "1140 Bluetooth-wireless radio switch FPC" on page 91 • "1150 System board, fan assembly, 34-mm ExpressCard reader, and base cover" on page - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 114
Integrated camera, microphone, or hall sensor card" on page 104 • "2040 LED sub card" on page 106 Removal steps of LCD cable 1 2 Cable routing: When you install the LCD cable, route the cable as shown in the figure above. 2060 Hinge kit For access, remove these FRUs in order: • "1010 Battery pack - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 115
• "2020 LCD panel" on page 102 • "2030 Integrated camera, microphone, or hall sensor card" on page 104 • "2040 LED sub card" on page 106 • "2050 LCD cable" on page 107 Removal steps of hinge kit 1 1 Step 1 Screw (quantity) M2 × 5 mm, bind-head, nylon-coated (2) Color Black - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 116
" on page 90 • "1140 Bluetooth-wireless radio switch FPC" on page 91 • "1150 System board, fan assembly, 34-mm ExpressCard reader, and base cover" on page 93 • "2010 LCD bezel assembly" on page 101 • "2020 LCD panel" on page 102 • "2030 Integrated camera, microphone, or hall sensor card" on page 104 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 117
, remove these FRUs in order: • "1010 Battery pack" on page 68 • "1020 Serial Ultrabay Slim device or travel bezel" on page 69 • "1030 Solid state drive (SSD) or hard disk drive (HDD)" on page 70 • "1040 DIMM" on page 72 • "1050 PCI Express Mini Card for wireless LAN" on page 74 • "1060 PCI - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 118
Bluetooth-wireless radio switch FPC" on page 91 • "1150 System board, fan assembly, 34-mm ExpressCard reader, and base cover" on page 93 • "2010 LCD bezel assembly" on page 101 • "2020 LCD panel" on page 102 • "2030 Integrated camera, microphone, or hall sensor card : 112 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 119
When you install the antenna kit, route the cables as shown in the figures below. As you route the cables, make sure that they are not subjected to any tension. Tension could cause the cables to be damaged by the cable guides, or a wire to be broken. Chapter 8. Removing and replacing a FRU 113 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 120
114 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 121
presents the locations of the ThinkPad T420s and T420si hardware components. Front view 3 1 2 3 4 17 5 9 6 15 14 13 16 12 11 7 8 9 10 1 Integrated camera (for some models) 2 ThinkLight light 3 Built-in microphone 4 ThinkVantage button 5 Power switch 6 Status indicators1 7 Security - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 122
ac power connector 1: For the description of each indicator, see Chapter 5 "Status indicators" on page 57. Bottom view 8 7 1 2 6 5 4 1 Expansion slot (DIMM, PCI Express Mini Card for wireless LAN and wireless WAN) 2 Docking connector 3 Solid state drive (SSD) or hard disk drive (HDD) 4 Battery - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 123
no more than two screws. Examples of these types of CRUs include the ac power adapter, power cord, battery, and hard disk drive. Other Self-service CRUs depending on product design may include the memory module, wireless card, keyboard, and palm rest with finger print reader and touchpad. - Optional - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 124
Overall 25 24 23 22 21 20 19 18 17 16 15 b 14 13 12 118 Hardware Maintenance Manual 1 2 3 4 18 5 6 7 8 9 10 11 a - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 125
, NVx, P6x, P8x, P9x, PAx, PBx, PCx, PFx, PGx, PKx, PLx, PMx, PNx 04W1711 * 4 Speaker assembly 04W1688 * 5 ThinkPad 1x1 11b/g/n Wireless LAN PCI Express Half Mini Card Adapter • 4170-CTO, 37x, 3Dx • 4171-CTO, 6Qx • 4172-CTO • 4173-CTO, J7x, JTx, K9x • 4174-CTO, NEx 60Y3247 ** 5 Intel Centrino - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 126
-CTO 60Y3239 ** 6 Integrated Mobile Broadband (Gobi 3000) • 4170-CTO • 4171-CTO, 5Tx • 4172-CTO • 4173-CTO, JLx • 4174-CTO 60Y3257 ** 6 Integrated Mobile Broadband (Gobi 3000), for Malaysia sku • 4170-CTO • 4171-CTO • 4172-CTO • 4173-CTO • 4174-CTO 60Y3283 ** 120 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 127
, PEx, PFx, PGx, PHx, PJx, PKx, PLx, PMx, PNx, PPx 8 Bluetooth-wireless radio switch FPC 04W1687 N 8 Bluetooth-wireless sub card 04W1700 N 9 DC-in sub card 04W1699 N 10 Second HDD adapter • 4170-CTO, 38x • 4171-CTO • 4172-CTO • 4173-CTO, JMx, JSx, JTx, JWx • 4174-CTO, 2Ax 43N3429 ** 11 DVD - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 128
, PHx, PJx, PKx, PLx, PMx, PNx, PPx 11 Travel cover • 4170-CTO, 3Bx • 4171-CTO • 4172-CTO • 4173-CTO, JZx, KGx, KJx • 4174-CTO 45M2657 * 12 Battery pack, Li-ion (6 cell) 59+ 42T4845 * • 4170-CTO, 32x, 33x, 34x, 35x, PFx, PGx, PHx, PJx, PKx, PLx, PMx, PNx, PPx 122 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 129
-Overall (continued) No. FRU (Overall) 13 HDD sub card • 4170-CTO • 4171-CTO • 4172-CTO • 4173-CTO • 4174-CTO 14 Base cover assembly 15 HDD rubber • 4170-CTO • 4171-CTO • 4172-CTO • 4173-CTO • 4174-CTO 15 SSD spacer • 4170-CTO • 4171-CTO • 4172-CTO • 4173-CTO • 4174-CTO 16 Hard disk drive, 250 GB - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 130
adapter 04W1701 N 18 Fan assembly, integrated 04W0416 N 04W1712 18 Fan assembly, Optimus 04W0417 N 04W1713 19 Express card slot frame 04W1689 N 20 System board assembly, with Intel Core i5-2520M processor, integrated, AMT, TPM, AES 04W2002 N • 4170-CTO, 34x, 3Ax, 3Bx, 3Ex, 3Hx • 4171 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 131
-CTO 04W2009 N 20 System board assembly, with Intel Core i3-2310M processor, Optimus, non-AMT, non-TPM, non-AES • 4170-CTO, 3Cx • 4171-CTO, 64x, 65x, 6Qx • 4172-CTO • 4173-CTO • 4174-CTO, N9x, NAx 04W2019 N 20 System board assembly, with Intel Core i5-2520M processor, integrated, non-AMT, TPM - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 132
i7-2620M Optimus, none-AMT, none-TPM, none-AES 04W2018 N • 4170-CTO, 33x • 4171-CTO, 6Mx • 4172-CTO • 4173-CTO • 4174-CTO 20 System board assembly, with Intel Core i3-2350M Optimus, none-AMT, TPM, AES • 4170-CTO • 4171-CTO • 4172-CTO • 4173-CTO • 4174-CTO 04W3469 N 126 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 133
, AES • 4170-CTO • 4171-CTO • 4172-CTO • 4173-CTO • 4174-CTO 20 System board assembly, with Intel Core i7-2640M integrated, none-AMT, TPM, AES • 4170-CTO • 4171-CTO • 4172-CTO • 4173-CTO • 4174-CTO 21 1-GB DDR3-1333 SDRAM SO-DIMM card • 4170-CTO, 33x • 4171-CTO • 4172-CTO, 22x • 4173-CTO, JXx, JYx - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 134
PNx, PPx 22 Backup battery 23 mSATA, 80 GB • 4170-CTO, 32x • 4171-CTO, 75x • 4172-CTO • 4173-CTO • 4174-CTO 24 Keyboard (see "Keyboard" on page 133.) FRU no. CRU ID 55Y3716 * 55Y3717 * 04W3253 ** 45N8259 ** 25 TrackPoint caps - Thermal grease - ac power adapter (see "ac power adapter" on page 134 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 135
34x, 35x, 36x, 37x, 38x, 39x, 3Ax, 3Bx, 3Cx, 3Dx, 3Ex, 3Fx, 3Gx, 3Hx • 4171-CTO, 52x, 53x, 54x, 55x, 5Ax, 5Bx, 5Dx, 5Ex, 5Fx, 5Hx, 5Jx, 5Mx, 5Nx, 77x, 78x, 79x, 7Ax, 7Bx, 7Cx, 7Dx, 7Ex, 7Fx • 4172-CTO, 22x, 23x, 24x • 4173-CTO, 28x, 29x, 2Ax, 2Bx, J2x, J4x, J7x, J8x, J9x, JAx, JBx, JCx, JDx, - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 136
P5x, P6x, P8x, P9x, PAx, PBx, PCx, PDx, PEx, PFx, PGx, PHx, PJx, PKx, PLx, PMx, PNx, PPx 3 Antenna kit • 4170-CTO • 4171-CTO • 4172-CTO • 4173-CTO • 4174-CTO 04W1683 N 04W1684 4 Microphone sub card • 4170-CTO • 4171-CTO • 4172-CTO • 4173-CTO • 4174-CTO 04W1697 N 130 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 137
ID 4 Integrated camera 60Y9994 N • 4170-CTO, 32x, 33x, 34x, 35x, 36x, 37x, 38x, 39x, 3Ax, 3Bx, 3Cx, 3Dx, 3Ex, 3Fx, 3Gx, 3Hx • 4171-CTO, , PGx, PHx, PJx, PKx, PLx, PNx, PPx 4 Hall sensor sub card • 4170-CTO • 4171-CTO • 4173-CTO • 4174-CTO 04W1678 N 5 LED cable assembly 04W1685 N • 4170-CTO - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 138
4171- 4173- 4171-CTO • 4172-CTO • 4173 -CTO • 4174-CTO 04W1705 N 8 Hinge kit 04W3413 N • 4170-CTO, 23x, 24x, 25x, 26x, 27x, 32x, 33x, 34x, 35x, 36x, 37x, 38x, 39x, 3Ax, 3Bx, 3Cx, 04W3414 3Dx, 3Ex, 3Fx, 3Gx, 3Hx • 4171 4173- 4171-CTO • 4172-CTO • 4173-CTO • 4174-CTO 04W1707 N 9 LCD cable - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 139
American Spanish Norwegian Polish Portuguese Russian Slovak Slovenian Spanish Swiss Thai Traditional Chinese Turkish U.K. English U.S. English U.S. English (International, with a Euro symbol) FRU no. 45N2076 45N2077 45N2075 45N2078 45N2073 45N2072 45N2079 45N2080 45N2090 45N2097 45N2082 45N2083 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 140
assembly • Express dummy card • Connector cap Note: Italicized letters in parentheses are references to the exploded view in "Overall" on page 118. LCD miscellaneous parts 04W1695 N ac power adapter Table 15. Parts list-2-pin ac power adapters FRU 2-pin (65 W, 20 V) adapter (models CTO, xxE - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 141
2-pin ac(90 W, 100 - 240 V) and 3-pin dc (90 W, 10.5 - 18V) combo adapter (models CTO, xxE, xxF, xxJ, xxG, xxP, xxS, xxU, xxY) FRU no. 41R0140 CRU ID * Power cords Table 18. Parts list-2-pin power cords Country or region Argentina • models -CTO, xxY Brazil • models -CTO, xxP Canada, U.S. • models - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 142
the system, that model is eligible only for recovery DVDs that match the operating system specified on the COA. Windows Vista Home Basic (32 bit) is preinstalled as the operating system in the following models: • 4170-CTO • 4171-CTO • 4172-CTO • 4173-CTO • 4174-CTO 136 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 143
04T3645 CRU ID * Windows 7 Home Basic (32 bit) DVDs Windows 7 Home Basic (32 bit) is preinstalled as the operating system in the following models: • 4170-CTO, 36x • 4171-CTO, 6Ex • 4172-CTO, 22x • 4173-CTO, KLx, KMx, KNx, KVx, KWx, L3x, LEx • 4174-CTO Table 23. Parts list-Windows 7 Home Basic (32 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 144
as the operating system in the following models: • 4170-CTO • 4171-CTO • 4172-CTO • 4173-CTO • 4174- the operating system in the following models: • 4170-CTO • 4171-CTO • 4172-CTO • 4173-CTO • as the operating system in the following models: • 4170-CTO • 4171-CTO • 4172-CTO • 4173-CTO • 4174-CTO - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 145
CRU ID * Windows 7 Home Premium (64 bit) DVDs Windows 7 Home Premium (64 bit) is preinstalled as the operating system in the following models: • 4170-CTO, 3Ex • 4171-CTO • 4172-CTO • 4173-CTO • 4174-CTO, NNx Table 28. Parts list-Windows 7 Home Premium (64 bit) recovery DVDs Language P/N Arabic - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 146
(32 bit) DVDs Windows 7 Professional (32 bit) is preinstalled as the operating system in the following models: • 4170-CTO • 4171-CTO, 6Fx, 6Gx, 6Yx • 4172-CTO • 4173-CTO, J7x, J8x, JCx, JDx, JEx, JHx, JTx, JVx, JWx, 04T1397 04T1401 04T1403 04T1404 CRU ID CRU ID * 140 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 147
preinstalled as the operating system in the following models: • 4170-CTO, 32x, 33x, 34x, 35x, 37x, 38x, 39x, 3Ax, 3Bx, 3Cx, 3Fx, 3Gx, 3Hx • 4171-CTO, 52x, 53x, 79x, 7Ax, 7Bx, 7Cx, 7Dx, 7Ex, 7Fx, 7Gx, 7Hx • 4172-CTO, 23x, 24x • 4173-CTO, 28x, 29x, 2Ax, 2Bx, J2x, J4x, J9x, JAx, JBx, JFx, JGx, JJx, JKx - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 148
as the operating system in the following models: • 4170-CTO, 3Dx • 4171-CTO • 4172-CTO • 4173-CTO • 4174-CTO Test card for integrated Smart Card LENOVO ThinkPad Hardware Maintenance Diskette Version 1.76 or later Note: Download the file from the following Web site: http://www.lenovo.com/support - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 149
that these measurements will be the same on generally available systems. Furthermore, some measurements may have been estimated through extrapolation. Actual results may vary. Users of this document should verify the applicable data for their specific environment. © Copyright Lenovo 2012 143 - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 150
User Guide. 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 , product, or service names may be the trademarks or service marks of others. 144 Hardware Maintenance Manual - Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 151
- Lenovo ThinkPad T420s | Hardware Maintenance Manual - Page 152
Part Number: 0A60241_04 Printed in China (1P) P/N: 0A60241_04 *0A60241_04*
Hardware Maintenance Manual
ThinkPad T420s and T420si