Lenovo ThinkBook 14 G4 IAP Owner's manual

Hardware Maintenance Manual
Lenovo ThinkBook 14 Gen 4 and Lenovo ThinkBook 15 Gen 4

First Edition (March 2022)
© Copyright Lenovo 2022.

Contents
About this manua . . . . . . . . . . . . iii
Chapter 1. Safety information . . . . . . 1
General safety . . . . . . . . . . . . . . . . 1
Electrical safety . . . . . . . . . . . . . . . . 1
Safety ins ection guide . . . . . . . . . . . . . 2
Handling devices that are sensitive to electrostatic
discharge . . . . . . . . . . . . . . . . . . 3
Grounding requirements . . . . . . . . . . . . 4
Safety notices (multilingual translations) . . . . . . 4
Chapter 2. Genera checkout . . . . . 21
What to do first . . . . . . . . . . . . . . . 21
CRU list . . . . . . . . . . . . . . . . . . 22
Chapter 3. Identifying FRUs
(CRUs) . . . . . . . . . . . . . . . . . 23
Locate FRUs and CRUs . . . . . . . . . . . 23
Chapter 4. Removing a FRU or
CRU . . . . . . . . . . . . . . . . . . 33
Service tools . . . . . . . . . . . . . . . . 33
General guidelines. . . . . . . . . . . . . . 33
Removal rocedure for ThinkBook 14 G4 IAP and
ThinkBook 14 G4 ABA . . . . . . . . . . . . 34
Remove the lower case . . . . . . . . . . 34
Remove the battery ack . . . . . . . . . 35
Remove the 2242 solid-state drive (SSD) . . . 36
Remove the 2280 solid-state drive (SSD) and
thermal ad . . . . . . . . . . . . . . . 36
Remove the 2nd solid-state drive (SSD) . . . . 38
Remove the 2nd solid-state drive (SSD)
bracket . . . . . . . . . . . . . . . . 38
Remove the Wi-Fi card . . . . . . . . . . 39
Remove the heat sink (for ThinkBook 14 G4
IAP and ThinkBook 15 G4 IAP only) . . . . . 40
Remove the fan (for ThinkBook 14 G4 IAP and
ThinkBook 15 G4 IAP only). . . . . . . . . 41
Remove the thermal module (for ThinkBook
14 G4 ABA and ThinkBook 15 G4 ABA only) . . 42
Remove the memory module . . . . . . . . 43
Remove the CMOS battery . . . . . . . . 44
Remove the I/O bracket (left) . . . . . . . . 44
Remove the I/O bracket (right) . . . . . . . 45
Remove the I/O board with cable . . . . . . 46
Remove the ower board with cable . . . . . 47
Remove the finger rint board with cable . . . 49
Remove the lens light guide . . . . . . . . 50
Remove the s eakers. . . . . . . . . . . 51
Remove the system board . . . . . . . . . 51
Remove the LCD module . . . . . . . . . 53
Remove the u er case (with keyboard and
touch ad) . . . . . . . . . . . . . . . 54
Disassemble the LCD module . . . . . . . 55
Removal rocedure for ThinkBook 15 G4 IAP and
ThinkBook 15 G4 ABA . . . . . . . . . . . . 62
Remove the lower case . . . . . . . . . . 62
Remove the battery ack . . . . . . . . . 63
Remove the 2242 solid-state drive (SSD) . . . 63
Remove the solid-state drive (SSD) . . . . . 64
Remove the 2nd solid-state drive (SSD) . . . . 65
Remove the 2nd solid-state drive (SSD)
bracket . . . . . . . . . . . . . . . . 66
Remove the Wi-Fi card . . . . . . . . . . 66
Remove the memory module . . . . . . . . 68
Remove the CMOS battery . . . . . . . . 69
Remove the I/O bracket (left) . . . . . . . . 70
Remove the I/O bracket (right) . . . . . . . 70
Remove the I/O board with cable . . . . . . 71
Remove the ower board with cable . . . . . 73
Remove the finger rint board with cable . . . 74
Remove the lens light guide . . . . . . . . 74
Remove the s eakers. . . . . . . . . . . 75
Remove the system board . . . . . . . . . 75
Remove the LCD module . . . . . . . . . 77
Remove the u er case (with keyboard and
touch ad) . . . . . . . . . . . . . . . 78
Disassemble the LCD module . . . . . . . 78
Appendix A. Labe ocations. . . . . . 85
Trademarks . . . . . . . . . . . . . . . lxxxix
© Co yright Lenovo 2022 i

ii Hardware Maintenance Manual

About this manua
This manual contains service and reference information for the following Lenovo roducts.
Machine Machine type (MT)
ThinkBook 14 G4 IAP 21DH
ThinkBook 14 G4 ABA 21DK
ThinkBook 15 G4 IAP 21DJ
ThinkBook 15 G4 ABA 21DL
Important:
• This manual is intended only for trained service technicians who are familiar with Lenovo roducts.
• Before servicing a Lenovo roduct, be sure to read all the information under Cha ter 1 “Safety
information” on age 1.
© Co yright Lenovo 2022 iii

iv Hardware Maintenance Manual

Chapter 1. Safety information
This cha ter resents the following safety information that you need to be familiar with before you service a
Lenovo notebook com uter.
Genera safety
Follow these rules to ensure general safety:
• Observe good housekee ing in the area of the machines during and after maintenance.
• When lifting any heavy object:
1. Make sure that you can stand safely without sli ing.
2. Distribute the weight of the object equally between your feet.
3. Use a slow lifting force. Never move suddenly or twist when you attem t to lift.
4. Lift by standing or by ushing u 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 erform any action that causes hazards to the customer, or that makes the equi ment unsafe.
• Before you start the machine, make sure that other service technicians and the customer's ersonnel are
not in a hazardous osition.
• Place removed covers and other arts in a safe lace, away from all ersonnel, while you are servicing the
machine.
• Kee your tool case away from walk areas so that other eo le will not tri over it.
• Do not wear loose clothing that can be tra ed in the moving arts of a machine. Make sure that your
sleeves are fastened or rolled u 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 non-conductive cli , about 8
centimeters (3 inches) from the end.
• Do not wear jewelry, chains, metal-frame eyeglasses, or metal fasteners for your clothing.
Attention: Metal objects are good electrical conductors.
• Wear safety glasses when you are hammering, drilling, soldering, cutting wire, attaching s rings, 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. Re lace any safety device that
is worn or defective.
• Reinstall all covers correctly before returning the machine to the customer.
• Fan louvers on the machine hel to revent overheating of internal com onents. Do not obstruct fan
louvers or cover them with labels or stickers.
E ectrica safety
Observe the following rules when working on electrical equi ment.
Important: Use only a roved tools and test equi ment. 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 equi ment, rubber floor mats that contain small conductive fibers to decrease electrostatic discharges.
Do not use this ty e of mat to rotect yourself from electrical shock.
• Find the room emergency ower-off (EPO) switch, disconnecting switch, or electrical outlet. If an electrical
accident occurs, you can then o erate the switch or un lug the ower cord quickly.
• Do not work alone under hazardous conditions or near equi ment that has hazardous voltages.
• Disconnect all ower before:
– Performing a mechanical ins ection
– Working near ower su lies
© Co yright Lenovo 2022 1

– Removing or installing main units
• Before you start to work on the machine, un lug the ower cord. If you cannot un lug it, ask the customer
to ower-off the wall box that su lies ower to the machine, and to lock the wall box in the off osition.
• If you need to work on a machine that has e posed electrical circuits, observe the following recautions:
– Ensure that another erson, familiar with the ower-off controls, is near you.
Attention: Another erson must be there to switch off the ower, if necessary.
– Use only one hand when working with owered-on electrical equi ment; kee the other hand in your
ocket or behind your back.
Attention: An electrical shock can occur only when there is a com lete circuit. By observing the above
rule, you may revent a current from assing through your body.
– When using testers, set the controls correctly and use the a roved robe leads and accessories for
that tester.
– Stand on suitable rubber mats (obtained locally, if necessary) to insulate you from grounds such as
metal floor stri s and machine frames.
Observe the s ecial safety recautions when you work with very high voltages; Instructions for these
recautions are in the safety sections of maintenance information. Use extreme care when measuring high
voltages.
• Regularly ins ect and maintain your electrical hand tools for safe o erational condition.
• Do not use worn or broken tools and testers.
• Never assume that ower has been disconnected from a circuit. First, check that it has been owered off.
• Always look carefully for ossible hazards in your work area. Exam les of these hazards are moist floors,
non-grounded ower extension cables, ower surges, and missing safety grounds.
• Do not touch live electrical circuits with the reflective surface of a lastic dental mirror. The surface is
conductive; such touching can cause ersonal injury and machine damage.
• Do not service the following arts with the power on when they are removed from their normal o erating
laces in a machine:
– Power su ly units
– Pum s
– Blowers and fans
– Motor generators
– Similar units as listed above
This ractice ensures correct grounding of the units.
• If an electrical accident occurs:
– Use caution; do not become a victim yourself.
– Switch off ower.
– Send another erson to get medical aid.
Safety inspection guide
The ur ose of this ins ection guide is to assist you in identifying otentially unsafe conditions. As each
machine was designed and built, required safety items were installed to rotect users and service
technicians from injury. This guide addresses only those items. You should use good judgment to identify
otential safety hazards due to attachment of non-Lenovo features or o tions not covered by this ins ection
guide.
If any unsafe conditions are resent, you must determine how serious the a arent hazard could be and
whether you can continue without first correcting the roblem.
Consider these conditions and the safety hazards they resent:
• Electrical hazards, es ecially rimary ower ( rimary voltage on the frame can cause serious or fatal
electrical shock)
• Ex losive hazards, such as a damaged cathode ray tube (CRT) face or a bulging ca acitor
• Mechanical hazards, such as loose or missing hardware
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To determine whether there are any otentially unsafe conditions, use the following checklist at the
beginning of every service task. Begin the checks with the ower off, and the ower cord disconnected.
Checklist:
1. Check exterior covers for damage (loose, broken, or shar edges).
2. Power off the com uter. Disconnect the ower cord.
3. Check the ower 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 in and the frame ground.
b. The ower cord should be the authorized ty e s ecified for your com uter. Go to: htt ://
www.lenovo.com/service arts-looku
c. Insulation must not be frayed or worn.
4. Check for cracked or bulging batteries.
5. Remove the cover.
6. Check for any obvious non-Lenovo alterations. Use good judgment as to the safety of any 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 inched cables.
9. Check that the ower-su ly cover fasteners (screws or rivets) have not been removed or tam ered
with.
Hand ing devices that are sensitive to e ectrostatic discharge
Any com uter art 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 art, the work mat, and the
erson handling the art are all at the same charge.
Notes:
1. Use roduct-s ecific ESD rocedures when they exceed the requirements noted here.
2. Make sure that the ESD rotective devices you use have been certified (ISO 9000) as fully effective.
When handling ESD-sensitive arts:
• Kee the arts in rotective ackages until they are inserted into the roduct.
• Avoid contact with other eo le.
• Wear a grounded wrist stra against your skin to eliminate static on your body.
• Prevent the art from touching your clothing. Most clothing is insulative and retains a charge even when
you are wearing a wrist stra .
• Use a grounded work mat to rovide a static-free work surface. The mat is es ecially useful when
handling ESD-sensitive devices.
• Select a grounding system, such as those listed below, to rovide rotection that meets the s ecific
service requirement.
Note: The use of a grounding system to guard against ESD damage is desirable but not necessary.
– Attach the ESD ground cli to any frame ground, ground braid, or green-wire ground.
– When working on a double-insulated or battery-o erated system, use an ESD common ground or
reference oint. You can use coax or connector-outside shells on these systems.
– Use the round ground rong of the ac lug on ac-o erated com uters.
Cha ter 1.Safety information 3

Grounding requirements
Electrical grounding of the com uter is required for o erator safety and correct system function. Pro er
grounding of the electrical outlet can be verified by a certified electrician.
Safety notices (mu ti ingua trans ations)
The safety notices in this section are rovided in the following languages:
• English
• Arabic
• Brazilian Portuguese
• French
• German
• Hebrew
• Ja anese
• Korean
• S anish
• Traditional Chinese
DANGER
DANGER
DANGER
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DANGER
DANGER
DANGER
DANGER
DANGER
Cha ter 1.Safety information 5

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PERIGO
PERIGO
PERIGO
Cha ter 1.Safety information 7

PERIGO
PERIGO
PERIGO
PERIGO
PERIGO
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DANGER
DANGER
DANGER
DANGER
Cha ter 1.Safety information 9

DANGER
DANGER
DANGER
DANGER
VORSICHT
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VORSICHT
VORSICHT
VORSICHT
VORSICHT
Cha ter 1.Safety information 11

VORSICHT
VORSICHT
VORSICHT
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Cha ter 1.Safety information 13

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