IBM Thinkpad T20 T21 T22 T23 Manual

							Power system checkout
To verify a symptom, do the following:
1. Power off the computer.
2. Remove the battery pack.
3. Connect the ac adapter.
4. Check that power is supplied when you power on the
computer.
5. Power off the computer.
6. Disconnect the ac adapter and install the charged
battery pack.
7. Check that the battery pack supplies power when you
power on the computer.
If you suspect a power problem, see the appropriate one
of the following power supply checkouts:
v“Checking the ac adapter”
v“Checking operational charging”on page 36
v“Checking the battery pack”on page 36
v“Checking the backup battery”on page 37
Checking the ac adapterYou are here because the computer fails only when the ac
adapter is used:
vIf the power problem occurs only when the port
replicator is used, replace the port replicator.
vIf the power-on indicator does not turn on, check the
power cord of the ac adapter for correct continuity and
installation.
vIf the computer does not charge during operation, go to
“Checking operational charging”.
To check the ac adapter, do the following:
1. Unplug the ac adapter cable from the computer.
2. Measure the output voltage at the plug of the ac
adapter cable. See the following figure:
2
1
(16-10V)
Pin Voltage (V dc)
1 +15.5 to +17.0
2 Ground
3. If the voltage is not correct, replace the ac adapter.
4. If the voltage is acceptable, do the following:
vReplace the system board.
vIf the problem persists, go to“Product overview”on
page 41.
Note:Noise from the ac adapter does not always indicate
a defect.
Checkout guide
General descriptions35 
						

							Checking operational chargingTo check whether the battery charges properly during
operation, use a discharged battery pack or a battery pack
that has less than 50% of the total power remaining when
installed in the computer.
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. Then reinstall the battery pack. If it is still
not charged, go to the next section.
Checking the battery packBattery charging does not start until the Power Meter
shows that less than 95% of the total power remains;
under this condition the battery pack can charge to 100%
of its capacity. This protects the battery pack from being
overcharged or from having a shortened life.
To check the status of your battery, move your cursor to
the Power Meter icon in the icon tray of the Windows
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 Meter icon.
Note:If the battery pack becomes hot, it may not be able
to charge. Remove it from the computer and leave it
at room temperature for a while. After it cools down,
reinstall and recharge it.
To check the battery pack, do the following:
1. Power off the computer.
2. Remove the battery pack and measure the voltage
between battery terminals 1 (+) and 5 (). See the
following figure:
2
3
4
5(-)1(+)
Terminal Voltage (V dc)
1 +0 to +12.6
5 Ground ()
3. If the voltage is less than +11.0 V dc, the battery pack
has been discharged.
Checkout guide
36ThinkPad T20, T21, T22, T23 (MT 2647/2648) 
						

							Note:Recharging will take at least 3 hours, even if the
indicator does not turn on.
If the voltage is still less than +11.0 V dc after
recharging, replace the battery.
4. If the voltage is more than +11.0 V dc, measure the
resistance between battery terminals 4 and 5. The
resistance must be 4 to 30 K.
If the resistance is not correct, replace the battery
pack. If the resistance is correct, replace the system
board.
Checking the backup batteryDo the following:
1. Power off the computer, and unplug the ac adapter
from it.
2. Turn the computer upside down.
3. Remove the battery pack (see“1010 Battery pack”on
page 60.)
4. Remove the backup battery (see“Checking the battery
pack”on page 36.)
5. Measure the voltage of the backup battery. See the
following figure.
Red (+)
Black (-)Wire Voltage (V dc)
Red +2.5 to +3.2
Black Ground
vIf the voltage is correct, replace the system board.
vIf the voltage is not correct, replace the backup battery.
vIf the backup battery discharges quickly after
replacement, replace the system board.
Checkout guide
General descriptions37 
						

							Checkout guide
38ThinkPad T20, T21, T22, T23 (MT 2647/2648) 
						

							ThinkPad T20, T21, T22 and T23
series
Product overview............41
Specifications............43
Status indicators...........45
FRU Tests.............47
Fn key combinations..........48
Symptom-to-FRU index..........49
Numeric error codes..........49
Error messages...........52
Beep symptoms...........53
No-beep symptoms..........53
LCD-related symptoms.........54
Intermittent problems..........55
Undetermined problems.........55
FRU replacement notices.........56
Screw notices............56
Retaining serial numbers.........57
Restoring the serial number of the system unit 57
Retaining the UUID.........57
Removing and replacing a FRU........59
1010 Battery pack...........60
1020 Backup battery..........61
1030 Hard-disk drive..........63
1040 DIMM............65
1050 Mini PCI adapter.........66
For T20, T21 and T22 series......66
For T23 series...........68
1060 Ethernet daughter card.......71
1070 Ultrabay 2000 device........73
1080 Keyboard...........74
For T20, T21 and T22 series......74
For T23 series...........75
1090 Keyboard CRU insulator.......82
1100 Hinge cover...........83
For T20 and T21 series........84
For T22 series...........86
For T23 series...........87
1110 Keyboard bezel..........88
For T20, T21 and T22 series......89
For T23 series...........92
1120 Fan assembly..........94
For T20, T21, T22 series........94
For T23 series...........97
1130CPU.............98
For T20, T21 and T22 series......98
For T23 series...........99
1140 PC Card slot assembly.......100
For T20, T21, T22 series.......100
For T23 series..........102
1150 Speaker...........103
© Copyright IBM Corp. 2002
39  
						

							1160 Hard-disk bay..........105
1170 Ultrabay 2000 slot........107
For T20 series..........107
For T21 and T22 series........108
For T23 series..........111
1180 System board..........113
For T20, T21, T22 series.......113
For T23 series..........115
1190 Secure chip..........117
1200 Microphone cable.........118
2010 LCD assembly..........121
2020 Front bezel...........122
2030 Inverter card..........123
2040 LCD panel...........125
2050 Antenna assembly........128
2060 Sub card...........131
3010 ThinkPad Dock PCI cover......133
3020 ThinkPad Dock top cover......136
Locations..............140
Front view............140
Rear view.............141
Bottom view............142
Parts list . .............143
T20, T21, T22 and T23 series model matrix 146
Overall.............147
For T20, T21 and T22........151
ForT23............156
AC adapters............156
LCD FRUs............157
13.3-in. XGA TFT.........157
14.1-in. XGA TFT.........158
14.1-in. SXGA+ TFT........159
Keyboard.............160
Recovery CDs...........161
For Windows 98 (T22 series)......161
For Windows 2000 (T22 series).....162
For Windows 2000/Windows NT (T22 series) 162
For Windows 98 (T23 series)......163
For Windows 2000 (T23 series).....164
For Windows 2000/Windows NT (T23 series) 165
For Windows XP (T23 series)......166
Miscellaneous parts..........170
Optional FRUs...........171
Common parts list..........172
Tools.............172
Power cords (system)........172
Power cords (docking station)......173
Notices . .............174
Trademarks............174
40ThinkPad T20, T21, T22, T23 (MT 2647/2648) 
						

							Product overview
This section presents the following product-unique
information:
v“Specifications”
v“Status indicators”on page 44
v“FRU Tests”on page 46
v“Fn key combinations”on page 48
Specifications
The following table lists the specifications of the ThinkPad
T20, T21, T22 and T23 series :
Feature Description
ProcessorT20
vMobile Intel
®Pentium®III processor 650 MHz
vMobile Intel®Pentium®III processor 700 MHz
vMobile Intel®Pentium®III processor 750 MHz
T21
vMobile Intel
®Pentium®III processor 750 MHz
vMobile Intel®Pentium®III processor 800 MHz
vMobile Intel®Pentium®III processor 850 MHz
T22
vMobile Intel
®Pentium®III processor 800 MHz
vMobile Intel®Pentium®III processor 900 MHz
vMobile Intel®Pentium®III processor 1 GHz
T23
vMobile Intel
®Pentium®III processor 866
MHz-M
vMobile Intel
®Pentium®III processor 1.0
GHz-M
vMobile Intel
®Pentium®III processor 1.13
GHz-M
vMobile Intel
®Pentium®III processor 1.2
GHz-M
Bus
architecturePCI Bus
Memory
(standard)T20, T21, T22
v128 MB (PC100) (on the system board)
T23
v128 MB (PC133) (on the system board)
v256 MB (PC133) (on the system board)
(continued)
Product overview
ThinkPad T20, T21, T22 and T23 series41 
						

							Feature Description
Memory
(optional)T20, T21, T22
v64 MB, 128 MB, or 256 MB DIMM card
(maximum of 512 MB)
T23
v64 MB, 128 MB, 256 MB, or 512 MB DIMM
card (maximum of 1024 MB)
CMOS RAM 242 bytes
DisplayT20
v13.3-inch, 16M colors, XGA (1024×768
resolution) TFT color LCD
v14.1-inch, 16M colors, XGA (1024×768
resolution) TFT color LCD
T21, T22, T23
v13.3-inch, 16M colors, XGA (1024×768
resolution) TFT color LCD
v14.1-inch, 16M colors, XGA (1024×768
resolution) TFT color LCD
v14.1-inch, 16M colors, SXGA+ (1400×1050
resolution) TFT color LCD
Hard-disk driveT20
v6.0 GB, 2.5-inch, IDE interface
v12.0 GB, 2.5-inch, IDE interface
v18.0 GB, 2.5-inch, IDE interface
v20.0 GB, 2.5-inch, IDE interface
T21, T22
v10.0 GB, 2.5-inch, IDE interface
v20.0 GB, 2.5-inch, IDE interface
v32.0 GB, 2.5-inch, IDE interface
T23
v15.0 GB, 2.5-inch, IDE interface
v20.0 GB, 2.5-inch, IDE interface
v30.0 GB, 2.5-inch, IDE interface
v40.0 GB, 2.5-inch, IDE interface
v48.0 GB, 2.5-inch, IDE interface
v60.0 GB, 2.5-inch, IDE interface
I/O portvExternal monitor
vLine-in
vHeadphone
vMicrophone
vMouse or keyboard
vParallel or diskette drive
vPort replicator connector
vSerial
vOne universal serial bus (USB) connector for
T20, T21, and T22 series
vTwo USB connectors for T23
vRJ11
vRJ45 (covered)
vTV-out
(continued)
Product overview
42ThinkPad T20, T21, T22, T23 (MT 2647/2648) 
						

							Feature Description
Internal
modem56.6 Kbps
AudiovInternal microphone
vInternal speaker
vSoftware control volume
Infrared
transferIrDA 1.1
802.11b (only
for T23 series)Mini PCI Type-IIIa IEEE 802.11b wireless LAN
card
PC Card One Type-III or two Type-II
AC adapter 72-watt type
Bay deviceT20
v1.44 MB (3-mode), 3.5-inch diskette drive
v10-24x CD-ROM drive
v6x DVD-ROM drive
T21, T22, T23
v1.44 MB (3-mode), 3.5-inch diskette drive
v10-24x CD-ROM drive
v8x DVD-ROM drive
vCD-RW drive
vDVD/CD-RW combo driveProduct overview
ThinkPad T20, T21, T22 and T23 series43 
						

							Status indicators
The system status indicators show the status of the
computer, as follows:
12345
678
Indicator Meaning

1Drive in useGreen:Data is being read from or written
to the hard-disk drive, the diskette
drive, or the drive in the Ultrabay
2000. When this indicator is on, do
not put the computer into standby
mode or turn off the computer.
Note:Do not move the system while the
Green drive in use light is on. Sudden physical
shock could cause drive errors.

2Num lockGreen:The numeric keypad on the
keyboard is enabled. To enable or
disable the keypad, press and hold
the Fn key while pressing the
NumLk key.

3Caps lockGreen:Caps Lock mode is enabled. To
enable or disable Caps Lock
mode, press Fn + Caps Lock key.
(continued)
Product overview
44ThinkPad T20, T21, T22, T23 (MT 2647/2648)