Lenovo ThinkPad X1 Carbon Gen 12 Owner's manual

ThinkPad X1 Carbon Gen 12
Hardware Maintenance Manual

First Edition (December 2023)
© Copyright Lenovo 2023.
LIMITED AND EST ICTED IGHTS NOTICE: If data or software is delivered pursuant to a General Services
Administration “GSA” contract, use, reproduction, or disclosure is subject to restrictions set forth in Contract No. GS-
35F-05925.

Contents
About this m nu l . . . . . . . . . . . . iii
Ch pter 1. S fety inform tion . . . . . . 1
General safety . . . . . . . . . . . . . . . . 1
Electrical safety . . . . . . . . . . . . . . . . 1
Safety inspection guide . . . . . . . . . . . . . 3
Handling devices that are sensitive to electrostatic
discharge . . . . . . . . . . . . . . . . . . 3
Grounding requirements . . . . . . . . . . . . 4
Safety notices (multilingual translations) . . . . . . 4
Ch pter 2. Import nt service
inform tion . . . . . . . . . . . . . . . 19
Strategy for replacing F Us . . . . . . . . . . 19
Strategy for replacing a solid-state drive . . . 19
How to use error message . . . . . . . . . 20
Strategy for replacing F Us for CTO, special-bid,
and standard models. . . . . . . . . . . . . 20
Product definition . . . . . . . . . . . . 20
F U identification . . . . . . . . . . . . 20
Ch pter 3. Gener l checkout . . . . . 21
What to do first . . . . . . . . . . . . . . . 21
Checkout guide . . . . . . . . . . . . . . . 22
Diagnosing problems . . . . . . . . . . . 22
Quick test programs . . . . . . . . . . . 23
UEFI diagnostic program . . . . . . . . . 23
Bootable diagnostic programs . . . . . . . 24
Power system checkout . . . . . . . . . . . 24
Checking the ac power adapter . . . . . . . 25
Checking the built-in battery and operational
charging . . . . . . . . . . . . . . . . 25
Checking the coin-cell battery . . . . . . . 25
Ch pter 4. Rel ted service
inform tion . . . . . . . . . . . . . . . 27
eset or restore Windows . . . . . . . . . . . 27
Passwords. . . . . . . . . . . . . . . . . 27
Power-on password . . . . . . . . . . . 27
NVMe passwords . . . . . . . . . . . . 27
Supervisor password . . . . . . . . . . . 28
System management password. . . . . . . 28
How to remove the power-on password . . . 29
How to remove the NVMe password . . . . . 29
How to remove the system management
password . . . . . . . . . . . . . . . 29
Power management . . . . . . . . . . . . . 30
Sleep mode . . . . . . . . . . . . . . 30
Hibernation mode . . . . . . . . . . . . 30
Symptom-to-F U index . . . . . . . . . . . 31
Numeric error codes . . . . . . . . . . . 32
Error messages . . . . . . . . . . . . . 33
Battery-charge LED indicator diagnosis . . . 33
No-beep symptoms . . . . . . . . . . . 35
LCD-related symptoms . . . . . . . . . . 36
Intermittent problems. . . . . . . . . . . 37
Undetermined problems . . . . . . . . . 37
Ch pter 5. Speci l keys . . . . . . . . 39
Ch pter 6. Loc tions . . . . . . . . . 41
Locating computer controls and connectors . . . 41
Front . . . . . . . . . . . . . . . . . 41
Side view . . . . . . . . . . . . . . . 42
Bottom . . . . . . . . . . . . . . . . 43
Locating F Us and C Us . . . . . . . . . . . 44
Major F Us and C Us . . . . . . . . . . 45
Miscellaneous parts . . . . . . . . . . . 47
Connector and cable guide . . . . . . . . 47
Looking up F U information . . . . . . . . . . 49
Ch pter 7. FRU repl cement
notices . . . . . . . . . . . . . . . . . 51
Service tool kit . . . . . . . . . . . . . . . 51
Screw notices . . . . . . . . . . . . . . . 51
etaining serial numbers . . . . . . . . . . . 52
estoring the serial number of the system
unit . . . . . . . . . . . . . . . . . . 52
etaining the UUID. . . . . . . . . . . . 53
eading or writing the ECA information . . . . 53
Ch pter 8. Removing or repl cing
FRU. . . . . . . . . . . . . . . . . . . 55
General guidelines. . . . . . . . . . . . . . 55
Before servicing the computer . . . . . . . . . 55
Disabling the built-in battery . . . . . . . . 55
emoving the nano-SIM-card and nano-SIM-
card tray . . . . . . . . . . . . . . . . 56
1010 Base cover assembly . . . . . . . . . . 56
1020 Built-in battery . . . . . . . . . . . . . 57
1030 M.2 solid-state drive and bracket . . . . . . 58
1040 Wireless WAN card (for selected models) . . 59
1050 Thermal fan assembly . . . . . . . . . . 62
1060 Speaker assembly . . . . . . . . . . . 63
1070 Trackpad, fingerprint reader, and P sensor
cable . . . . . . . . . . . . . . . . . . . 64
© Copyright Lenovo 2023 i

1080 Wireless WAN antenna assembly(for selected
models) . . . . . . . . . . . . . . . . . . 64
1090 Wireless WAN antenna cable guide rubber
(for selected models) . . . . . . . . . . . . . 65
1100 Coin-cell battery . . . . . . . . . . . . 66
1110 Fan cable guide . . . . . . . . . . . . 67
1120 USB bracket . . . . . . . . . . . . . . 67
1130 Trackpad and its spill mylar . . . . . . . . 68
1140 System board with SSD thermal pad . . . . 70
1150 LCD unit . . . . . . . . . . . . . . . 73
1170 Keyboard assembly . . . . . . . . . . . 74
Appendix A. Notices. . . . . . . . . . 75
Appendix B. Abbrevi tion t ble . . . . 77
ii ThinkPad X1 Carbon Gen 12 Hardware Maintenance Manual

About this m nu l
This manual contains service and reference information for the following products:
Product n me M chine type (MT)
ThinkPad X1 Carbon Gen 12 21KC and 21KD
Use this manual along with the advanced diagnostic tests to troubleshoot problems.
Import nt:
• This manual is intended only for trained service technicians who are familiar with products. Use this
manual along with the advanced diagnostic tests to troubleshoot problems effectively.
• Depending on the model, some hardware configuration and software programs might not be available on
the computer. Some statements in this manual might not be applicable to the computer.
• Before servicing a product, be sure to read all the information under Chapter 1 “Safety information” on
page 1 and Chapter 2 “Important service information” on page 19.
© Copyright Lenovo 2023 iii

iv ThinkPad X1 Carbon Gen 12 Hardware Maintenance Manual

Ch pter 1. S fety inform tion
This chapter presents following safety information that you need to be familiar with before you service a
notebook computer.
• “General safety” on page 1
• “Electrical safety” on page 1
• “Safety inspection guide” on page 3
• “Handling devices that are sensitive to electrostatic discharge” on page 3
• “Grounding requirements” on page 4
• “Safety notices (multilingual translations)” on page 4
Gener l s fety
Follow these rules to ensure general safety:
• Observe good housekeeping in the area of the machines during and after maintenance.
• When lifting any heavy object:
1. Ensure that you can stand safely without slipping.
2. Distribute the weight of the object equally between your feet.
3. Use a slow lifting force. Never move suddenly or twist when you attempt to lift.
4. Lift by standing or by pushing up with your leg muscles; this action removes the strain from the
muscles in your back. Do not attempt to lift any object that weighs more than 16 kg (35 lb) or that you
think is too heavy for you.
• Do not perform any action that causes hazards to the customer, or that makes the equipment unsafe.
• Before you start the machine, ensure that other service technicians and the customer's personnel are not
in a hazardous position.
• Place removed covers and other parts in a safe place, away from all personnel, while you are servicing the
machine.
• Keep your tool case away from walk areas so that other people will not trip over it.
• Do not wear loose clothing that can be trapped in the moving parts of a machine. Ensure that your sleeves
are fastened or rolled up above your elbows. If your hair is long, fasten it.
• Insert the ends of your necktie or scarf inside clothing or fasten it with a nonconductive clip, about 8
centimeters (3 inches) from the end.
• Do not wear jewelry, chains, metal-frame eyeglasses, or metal fasteners for your clothing, because metal
objects are good electrical conductors.
• Wear safety glasses when you are hammering, drilling, soldering, cutting wire, attaching springs, using
solvents, or working in any other conditions that might be hazardous to your eyes.
• After service, reinstall all safety shields, guards, labels, and ground wires. eplace any safety device that
is worn or defective.
• einstall all covers correctly before returning the 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 labels or stickers.
Electric l s fety
Observe the following rules when working on electrical equipment.
© Copyright Lenovo 2023 1

Import nt:
• 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 (ESD). Do not use this type of mat to protect yourself from electrical
shock.
• Find the room emergency power-off (EPO) switch, disconnecting switch, or electrical outlet. If an electrical
accident occurs, you can then operate the switch or unplug the power cord quickly.
• Do not work alone under hazardous conditions or near equipment that has hazardous voltages.
• Disconnect all power before:
– Performing a mechanical inspection
– Working near power supplies
– emoving or installing main units
• Before you start to work on the machine, unplug the power cord. If you cannot unplug it, ask the customer
to power off the wall box that supplies power to the machine, and to lock the wall box in the off position.
• If you need to work on a machine that has exposed electrical circuits, observe the following precautions:
– Ensure that another person, familiar with the power-off controls, is near you. That person must be there
to switch off the power, if necessary.
– Use only one hand when working with powered-on electrical equipment; keep the other hand in your
pocket or behind your back.
CAUTION:
An electric l shock c n occur only when there is complete circuit. By observing the bove rule,
you m y prevent current from p ssing through your body.
– When using testers, set the controls correctly and use the approved probe leads and accessories for
that tester.
– Stand on suitable rubber mats (obtained locally, if necessary) to insulate you from grounds such as
metal floor strips and machine frames.
Observe the special safety precautions when you work with very high voltages. Instructions for these
precautions are in the safety sections of maintenance information. Use extreme care when measuring high
voltages.
• egularly inspect and maintain your electrical hand tools for safe operational condition.
• Do not use worn or broken tools and testers.
• Never assume that power has been disconnected from a circuit. First, check that it has been powered off.
• Always look carefully for possible hazards in your work area. Examples of these hazards are moist floors,
nongrounded power extension cables, power surges, and missing safety grounds.
• Do not touch live electrical circuits with the reflective surface of a plastic dental mirror. The surface is
conductive; such touching can cause personal injury and machine damage.
• Do not service the following parts with the power on:
– Power supply units
– Fans
– Units similar to those 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.
– Send another person to get medical aid.
2ThinkPad X1 Carbon Gen 12 Hardware Maintenance Manual

S fety inspection guide
The purpose of this inspection guide is to assist you in identifying potentially unsafe conditions. As each
machine was 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 / non-Lenovo features or options not covered by
this inspection guide.
If any unsafe conditions are present, you must determine how serious the apparent hazard could be and
whether you can continue without first correcting the problem.
Consider these conditions and the safety hazards they present:
• Electrical hazards, especially primary power (primary voltage on the frame can cause serious or fatal
electrical shock)
• Explosive hazards, such as a damaged C T face or a bulging capacitor
• Mechanical hazards, such as loose or missing hardware
To determine whether there are any potentially unsafe conditions, use the following checklist at the
beginning of every service task. Begin the checks with the power off, and the power cord disconnected.
Checklist:
1. Check exterior covers for damage (loose, broken, or sharp edges).
2. Turn off the computer. Disconnect the power cord.
3. Check the power cord for:
a. A third-wire ground connector in good condition. Use a meter to measure third-wire ground
continuity for 0.1 ohm or less between the external ground pin and the frame ground.
b. The power cord should be the authorized type specified for your computer. Go to: https://
support.lenovo.com/partslookup.
c. Insulation must not be frayed or worn.
4. Check for cracked or bulging batteries.
5. emove the cover.
6. Check for any obvious non-ThinkPad / non-Lenovo alterations. Use good judgment as to the safety of
any non-ThinkPad / non-Lenovo alterations.
7. Check inside the unit for any obvious unsafe conditions, such as metal filings, contamination, water or
other liquids, or signs of fire or smoke damage.
8. Check for worn, frayed, or pinched cables.
9. Check that the power-supply cover fasteners (screws or rivets) have not been removed or tampered
with.
H ndling devices th t re sensitive to electrost tic disch rge
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.
Notes:
1. Use product-specific ESD procedures when they exceed the requirements noted here.
Chapter 1.Safety information 3

2. Ensure that the ESD protective devices you use have been certified (ISO 9000) as fully effective.
When handling ESD-sensitive parts:
• Keep the parts in protective packages until they are inserted into the product.
• Avoid contact with other people.
• Wear a grounded wrist strap against your skin to eliminate static on your body.
• Prevent the part from touching your clothing. Most clothing is insulative and retains a charge even when
you are wearing a wrist strap.
• Use a grounded work mat to provide a static-free work surface. The mat is especially useful when
handling ESD-sensitive devices.
• Select a grounding system, such as those listed below, to provide protection that meets the 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, use an ESD common ground or
reference point. You can use coax or connector-outside shells on these systems.
– Use the round ground prong of the ac plug on ac-operated computers.
Grounding requirements
Electrical grounding of the computer is required for operator safety and correct system function. Proper
grounding of the electrical outlet can be verified by a certified electrician.
S fety notices (multilingu l tr nsl tions)
The safety notices in this section are provided in the following languages:
• English
• Arabic
• Brazilian Portuguese
• French
• German
• Hebrew
• Japanese
• Korean
• Spanish
• Traditional Chinese
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