IBM Thinkpad T20 T21 T22 T23 Manual

							Indicator Meaning

4Scroll lockGreen:Scroll Lock mode is enabled. Arrow
keys can be used as screen-scroll
function keys, but not to move the
cursor. To enable or disable Scroll
Lock mode, press Fn + ScrLk key.
Not all application programs
support this function.

5Power onGreen:This indicator stays lighted
whenever the computer is on. If
the power-on indicator is on and
the standby indicator is off, the
system is ready to use. If both the
power-on indicator and the standby
indicator are on, you can use the
computer after it returns from the
standby mode and the standby
indicator goes off.

6BatteryGreen:The battery is fully charged.
Blinking green:
The battery has enough power to
operate, but is being charged.
Orange:The battery power is low. The
battery needs to be charged.
Blinking orange:
The battery needs to be charged
when the indicator starts blinking
orange, the computer beeps three
times.

7Standby
statusGreen:The computer is in standby mode.
Blinking green:
The computer is entering standby
mode or hibernation mode, or is
resuming normal operation. This
indicator does not blink in Windows
2000, Windows Me, and Windows
XP.

8Ultrabay
statusGreen:An Ultrabay 2000 device is
installed and in use.
Blinking green:
An Ultrabay 2000 device is in the
process of being detached.
Turn off:An Ultrabay 2000 device is ready
to be attached or detached.
Note:If you are using Windows 2000 or
Windows XP, the Ultrabay status indicator
does not blink while an Ultrabay 2000 device
is being detached. Instead, a message box
pops up when the process is completed; then
the indicator turns off.Product overview
ThinkPad T20, T21, T22 and T23 series45 
						

							FRU Tests
The following table shows the test for each FRU.
FRU Applicable test
System board 1.Diagnostics --> CPU/Coprocessor
2.Diagnostics --> Systemboard
PowerDiagnostics --> Other Devices --> IBM AC
Adapter, IBM Battery 1 (IBM Battery 2)
LCD unit 1.Diagnostics --> Video Adapter
2.Interactive Tests --> Video
Modem 1. Make sure the modem is set up correctly.
2. Replace the modem jack and the modem
card in turn, and run the following test in
Diagnostics --> Communication:
a. Lucent Modem (M2) Loopback
b. Lucent Modem (M2) Dialtone/DTM
c. Lucent Soft Modem Loopback (T23
only)
d. Lucent Soft Modem Dialtone (T23 only)
e. Intel Modem Register
f. Intel Modem Loopback/DTMF
g. Intel SP Modem Register
h. Intel SP Modem Loopback/DTMF
i. 3Com MiniPCI Modem Test
j. 3Com MiniPCI Dialtone Test
Audio 1.Interactive Tests --> Internal Speaker
2.Diagnostics --> Other Devices --> Crystal
SoundFusion
™Test
SpeakerInteractive Tests --> Internal Speaker
PC Card slotsDiagnostics --> Systemboard --> PCMCIA,
PCMCIA External Loop
Keyboard 1.Diagnostics --> Systemboard -->
Keyboard
2.Interactive Tests --> Keyboard
TrackPoint or
pointing deviceIf the TrackPoint does not work, check the
configuration in the ThinkPad Configuration
program. If the TrackPoint is disabled, select
Enableto 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. This symptom
is not a hardware problem. If the pointer stops
after a short time, no service action is
necessary.
If enabling the TrackPoint does not correct the
problem, continue with the following:
vInteractive Tests --> Mouse
Hard-disk driveDiagnostics --> Fixed Disks
(continued)
Product overview
46ThinkPad T20, T21, T22, T23 (MT 2647/2648) 
						

							FRU Applicable test
Diskette drive 1.Diagnostics --> Diskette Drives
2.Interactive Tests --> Diskette
CD-ROM, DVD,
CD-RW or
CD-RW/DVD
combo drive1.Diagnostics --> Other Devices -->
CD-ROM/DVD
2.Interactive Tests --> CD-ROM/DVD Test
Memory 1. If two DIMMs are installed, remove one of
them and runDiagnostics --> Memory
Test - Quick.
2. If the problem does not recur, return the
DIMM to its place, remove the other one,
and run the test again.
3. If the test does not detect the error, run
Diagnostics --> Memory Test - Full.
Fan 1. Turn on the computer and check the air
turbulence at the louver near the power
switch.
2. RunDiagnostics --> Other Devices -->
IBM Fan.Product overview
ThinkPad T20, T21, T22 and T23 series47 
						

							Fn key combinations
The following table shows the function of each combination
of Fn with a function key.
Key
combinationDescription
Fn+F1 Reserved.
Fn+F2 Reserved.
Fn+F3 Turn off the LCD display, leaving the screen
blank. To turn the LCD display on again, press
any key or the TrackPoint stick.
Note:To use Fn+F3 for screen blank in
Windows 2000 and Windows XP, you must have
IBM PM device driver installed on your
computer.
Fn+F4 Turn standby mode on. To return to normal
operation, press the Fn key independently,
without pressing a function key.
Fn+F5 Reserved.
Fn+F6 Reserved.
Fn+F7 Switch between the LCD and an external
monitor (CRT). If an external monitor is
attached, computer output is displayed in the
following three patterns by turns:
vCRT display
vLCD+CRT display
vLCD
Fn+F8 Turn screen expansion on or off. (There is no
symbol on the key.)
Note:This function is not supported in Windows
2000 and Windows XP.
Fn+F9 Reserved.
Fn+F10 Reserved.
Fn+F11 Reserved.
Fn+F12 Turn hibernation mode on. To return to normal
operation, press the power button for less than
four seconds.
Note:To use Fn+F12 for hibernation in
Windows 2000 and Windows XP, you must have
IBM PM device driver installed on your
computer.
Fn+PgUp Turn the ThinkLight on or off.
Fn+Home The LCD becomes brighter.
Fn+End The LCD becomes less bright. Product overview
48ThinkPad T20, T21, T22, T23 (MT 2647/2648) 
						

							Symptom-to-FRU index
The symptom-to-FRU index in this section lists symptoms
and errors and their possible causes. The most likely
cause is listed first, in boldface type.
Note:Do the FRU replacement or other actions in the
sequence shown in the column headed“FRU or
action, in sequence.”If replacing a FRU does not
solve the problem, put the original part back in the
computer. Do not replace a nondefective FRU.
This index can also help you determine, during regular
servicing, what FRUs are likely to need to be replaced
next.
A numeric error is displayed for each error detected in
POST or system operation. In the displays,ncan be any
number.
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 55.
NoteFor an IBM device not supported by diagnostic
codes in the ThinkPad notebook computers, see the
manual for that device.
Numeric error codes
Symptom or error FRU or action, in sequence
0175
Bad CRC1, stop POST
task—The EEPROM checksum
is not correct.System board.
0187
EAIA data access error—The
access to EEPROM is failed.System board.
0188
Invalid RFID serialization
information area or bad
CRC2—The EEPROM
checksum is not correct.System board.
0189
Invalid RFID configuration
information area—The
EEPROM checksum is not
correct.System board.
0190
Critical low-battery error1.Charge the battery pack.
2. Battery pack.Symptom-to-FRU index
ThinkPad T20, T21, T22 and T23 series49 
						

							Symptom or error FRU or action, in sequence
0193
RF antenna has been removedEnter the supervisor
password.
0194
The computer has been carried
through a security gateEnter the supervisor
password.
0195
Security hardware tamper
detected1.Enter IBM BIOS Setup
Utility by entering
supervisor password, and
select“Password”-->
“IBM Security Chip”-->
“Clear IBM Security Chip”
to clear this error.
2. Security chip.
3. System board.
0196
Security hardware removed1.Enter IBM BIOS Setup
Utility by entering
supervisor password, and
select“Password”-->
“IBM Security Chip”-->
“Clear IBM Security Chip”
to clear this error.
2. Security chip.
3. System board.
0197
Invalid remote change
requestedThe remote configuration for
the security chip has failed.
Confirm the operation and try
again.
01C9
More than one Ethernet devices
are found. Remove one of
them. Press  to continue.1.Remove the Ethernet
device that you installed;
or press Esc to ignore the
warning message.
2. System board.
0200
Hard disk error—The hard disk
is not working.1.Reseat the hard-disk
drive.
2. Load Setup Defaults in IBM
BIOS Setup Utility.
3. Hard-disk drive.
4. System board.
021x
Keyboard errorRun interactive tests of the
keyboard and the auxiliary
input device.
0220
Monitor type error—Monitor
type does not match the one
specified in CMOS.Load Setup Defaults in IBM
BIOS Setup Utility.
0230
Shadow RAM error—Shadow
RAM fails at offset nnnn.System board.
0231
System RAM error—System
RAM fails at offset nnnn.1.DIMM.
2. System board. Symptom-to-FRU index
50ThinkPad T20, T21, T22, T23 (MT 2647/2648) 
						

							Symptom or error FRU or action, in sequence
0232
Extended RAM
error—Extended RAM fails at
offset nnnn.1.DIMM.
2. System board.
0250
System battery error—System
battery is dead.Replace the backup battery
and run IBM BIOS Setup
Utility to reset the time and
date.
0251
System CMOS checksum
bad—Default configuration
used.Replace the backup battery
and run IBM BIOS Setup
Utility to reset the time and
date.
0252
Password checksum bad—The
password is cleared.Reset the password by
running IBM BIOS Setup
Utility.
0260
System timer error1.Replace the backup
battery and run IBM BIOS
Setup Utility to reset the
time and date.
2. System board.
0270
Real time clock error1.Replace the backup
battery and run IBM BIOS
Setup Utility to reset the
time and date.
2. System board.
0271
Date and time error—Neither
the date nor the time is set in
the computer.Run IBM BIOS Setup Utility to
reset the time and date.
02B2
Incorrect drive A type1.Diskette drive.
2. External FDD cable.
3. I/O card.
02F4
EISA CMOS not writable1.Load Setup Defaults in
IBM BIOS Setup Utility.
2. Replace the backup battery.
3. System board.
02F5
DMA test failed1.DIMM.
2. System board.
02F6
Software NMI failed1.DIMM.
2. System board.
02F7
Fail-safe timer NMI failed1.DIMM.
2. System board.Symptom-to-FRU index
ThinkPad T20, T21, T22 and T23 series51 
						

							Error messages
Symptom or error FRU or action, in sequence
Device address conflict. 1.Load“Setup Defaults”in
IBM BIOS Setup Utility.
2. Backup battery.
3. System board.
Allocation error for device. 1.Load“Setup Defaults”in
IBM BIOS Setup Utility.
2. Backup battery.
3. System board.
Failing bits: nnnn. 1.DIMM.
2. System board.
Invalid system configuration
data.1.DIMM.
2. System board.
I/O device IRQ conflict. 1.Load“Setup Defaults”in
IBM BIOS Setup Utility.
2. Backup battery.
3. System board.
Operating system not found. 1. Check that the operating
system has no failure and is
installed correctly.
2.Enter IBM BIOS Setup
Utility and see whether
the hard-disk drive and
the diskette drive are
properly identified.
3. Reseat the hard-disk drive.
4. Reinstall the operating
system.
5. Diskette drive.
6. Hard-disk drive.
7. System board.
Hibernation error. 1.Restore the system
configuration to what it
was before the computer
entered hibernation mode.
2. If memory size has been
changed, re-create the
hibernation file.
Fan error.Fan.
Thermal sensing error.System board. Symptom-to-FRU index
52ThinkPad T20, T21, T22, T23 (MT 2647/2648) 
						

							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
LCD.1.System board.
2. LCD assembly.
3. DIMM.
Two short beeps with error
codes.POST error. See“Numeric
error codes”on page 49.
Two short beeps and a blank
screen.1.System board.
2. DIMM.
Two or more beeps, or a
continuous beep. Operating
system starts successfully.If a mini-PCI Ethernet card is
installed, confirm thatAlert On
LAN 2in IBM BIOS Setup
Utility isdisabled.
Three short beeps, pause,
three more short beeps, and
one short beep.1.DIMM.
2. System board
One short beep, pause, three
short beeps, pause, three more
short beeps, and one short
beep.
Only cursor appears.Reinstall operating system.
No-beep symptoms
Symptom or error FRU or action, in sequence
No beep, power-on indicator
on, LCD blank, and no POST.1.Make sure that every
connector is connected
tightly and correctly.
2. DIMM.
3. System board.
No beep, power-on indicator
on, and LCD blank during
POST.1.Reseat DIMM.
2. System board.
The power-on password prompt
appears.A power-on password or a
supervisor password is set.
Type the password and press
Enter.
The hard-disk password prompt
appears.A hard-disk password is set.
Type the password and press
Enter.
The DOS full screen looks
smaller.Start the ThinkPad
Configuration program and set
theScreen expansion
function.Symptom-to-FRU index
ThinkPad T20, T21, T22 and T23 series53 
						

							LCD-related symptoms
ImportantThe TFT LCD for the notebook computer contains
many thin-film transistors (TFTs). A small number of
dots that are missing, discolored, or always lighted
is characteristic of TFT LCD technology, but
excessive pixel problems can cause viewing
concerns. The LCD should be replaced if the
number of missing, discolored, or lighted dots in any
background is:
vXGA:8 or more bright dots, 8 or more dark dots,
or a total of 9 or more bright and dark dots.
vSXGA+:11 or more bright dots, 13 or more dark
dots, or a total of 16 or more bright and dark
dots.
Note:A bright dot means a pixel is always on
(white or color.) A dark dot means a pixel is
always off (black color.)
Symptom or error FRU or action, in sequence
No beep, power-on indicator
on, and a blank LCD during
POST.System board.
vLCD backlight not working.
vLCD too dark.
vLCD brightness cannot be
adjusted.
vLCD contrast cannot be
adjusted.1.Reseat the LCD
connectors.
2. LCD assembly.
3. System board.
vLCD screen unreadable.
vCharacters missing pixels.
vScreen abnormal.
vWrong color displayed.1.See important note for
“LCD-related symptoms.”
2. Reseat all LCD connectors.
3. LCD assembly.
4. System board.
Horizontal or vertical lines
displayed on LCD.LCD assembly. Symptom-to-FRU index
54ThinkPad T20, T21, T22, T23 (MT 2647/2648)