Table Of Contents - Lenovo ThinkPad T420 Hardware Maintenance Manual

Contents
About this manual. . . . . . . . . . .
Chapter 1. Safety information . . . . . . 1
General safety . . . . . . . . . . . . . . . .
Electrical safety . . . . . . . . . . . . . . .
Safety inspection guide . . . . . . . . . . . .
Handling devices that are sensitive to electrostatic
discharge. . . . . . . . . . . . . . . . . .
Grounding requirements . . . . . . . . . . . .
Safety notices (multilingual translations) . . . . . .
Laser compliance statement (multilingual
translations) . . . . . . . . . . . . . . . .
Chapter 2. Important service
information . . . . . . . . . . . . . . 23
Strategy for replacing FRUs . . . . . . . . .
Strategy for replacing a hard disk drive . . .
Important notice for replacing a system
board . . . . . . . . . . . . . . . .
How to use error message . . . . . . . .
Strategy for replacing FRUs for CTO, CMV, and
GAV . . . . . . . . . . . . . . . . . . .
Product deinition . . . . . . . . . . . .
FRU identiication for CTO, CMV, and GAV
products . . . . . . . . . . . . . . .
Chapter 3. General checkout . . . . . 27
What to do irst . . . . . . . . . . . . . .
Checkout guide . . . . . . . . . . . . . .
Diagnostics using PC-Doctor for DOS. . . .
Lenovo ThinkVantage Toolbox . . . . . . .
FRU tests . . . . . . . . . . . . . . .
Power system checkout . . . . . . . . . . .
Checking the ac power adapter . . . . . .
Checking operational charging . . . . . .
Checking the battery pack . . . . . . . .
Checking the backup battery . . . . . . .
Chapter 4. Related service
information . . . . . . . . . . . . . . 37
Restoring the factory contents by using Recovery
Disc Set . . . . . . . . . . . . . . . . .
Passwords . . . . . . . . . . . . . . . .
Power-on password . . . . . . . . . . .
Hard-disk password. . . . . . . . . . .
Supervisor password . . . . . . . . . .
How to remove the power-on password . . .
How to remove the hard-disk password . . .
© Copyright Lenovo 2011
iii
Power management
Screen blank mode . . . . . . . . . . .
Sleep (standby) mode . . . . . . . . . .
1
Hibernation mode
2
Symptom-to-FRU index . . . . . . . . . . .
3
Numeric error codes
Error messages . . . . . . . . . . . .
3
Beep symptoms . . . . . . . . . . . .
4
No-beep symptoms . . . . . . . . . . .
5
LCD-related symptoms . . . . . . . . .
Intermittent problems . . . . . . . . . .
17
Undetermined problems . . . . . . . . .
Chapter 5. Status indicators . . . . . 49
23
Chapter 6. Fn key combinations . . . 53
23
Chapter 7. FRU replacement
24
notices . . . . . . . . . . . . . . . . 57
24
Screw notices . . . . . . . . . . . . . . .
Retaining serial numbers. . . . . . . . . . .
25
Restoring the serial number of the system
25
unit . . . . . . . . . . . . . . . . .
Retaining the UUID . . . . . . . . . . .
25
Reading or writing the ECA information . . .
Chapter 8. Removing and replacing a
28
FRU . . . . . . . . . . . . . . . . . . 61
29
Before servicing ThinkPad T420 and T420i
29
1010 Battery pack . . . . . . . . . . . . .
31
1020 ExpressCard blank bezel . . . . . . . .
33
1030 Serial Ultrabay Enhanced device or travel
34
bezel . . . . . . . . . . . . . . . . . .
34
1040 Hard disk drive (HDD) and solid state drive
34
(SSD) . . . . . . . . . . . . . . . . . .
35
1050 DIMM slot cover . . . . . . . . . . . .
35
1060 DIMM (in the slot on the underside of the
computer) . . . . . . . . . . . . . . . .
1070 PCI Express Mini Card for wireless WAN . .
1080 Keyboard . . . . . . . . . . . . . .
1090 DIMM (in the slot under the keyboard) . . .
37
1100 Backup battery . . . . . . . . . . . .
38
1110 PCI Express Mini Card for wireless LAN . .
38
1120 Keyboard bezel assembly, FPC cable, and
38
Bluethooth daughter card . . . . . . . . . .
39
1130 SmartCard . . . . . . . . . . . . . .
39
1140 Modem daughter card (MDC). . . . . . .
39
1150 Speaker assembly . . . . . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . .
. . . . . . . . . .
. . .
41
41
41
41
43
43
45
46
46
46
48
48
57
58
58
59
59
62
63
64
65
66
69
70
71
73
77
79
81
83
88
90
91
i