Lenovo ThinkCentre M75s Gen 2 Hardware Maintenance Manual [en, ar, bg, cs, da, de, el, es, fi, fr, he, hr, hu, id, it, ja, ko, nb, nl, pl, pt, ro, ru, sh, sk, sl, sv, th, tr, uk, zc, zh]

M75s Gen 2
Hardware Maintenance Manual

First Edition (November 2020)

© Copyright Lenovo 2020.

LIMITED AND RESTRICTED RIGHTS 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. GS­35F-05925.

Contents

About this manual . . . . . . . . . . . . iii

Chapter 1. Important safety

information. . . . . . . . . . . . . . . . 1

General safety . . . . . . . . . . . . . . . . 1

Electrical safety . . . . . . . . . . . . . . . . 2

Safety inspection guide. . . . . . . . . . . . . 3

Handling electrostatic discharge-sensitive

devices . . . . . . . . . . . . . . . . . . . 4

Grounding requirements . . . . . . . . . . . . 4

Safety notices (multi-lingual translations) . . . . . . 4

Chapter 2. Important service

information. . . . . . . . . . . . . . . 27

Strategy for replacing FRUs . . . . . . . . . . 27

Strategy for replacing a hard disk drive or a

solid-state drive . . . . . . . . . . . . . 27

Important notice for replacing a system

board . . . . . . . . . . . . . . . . . 27

How to use error codes . . . . . . . . . . 28

Strategy for replacing FRUs for CTO, special-bid,

and standard models. . . . . . . . . . . . . 28

Product definition . . . . . . . . . . . . 28

FRU identification . . . . . . . . . . . . 28

Chapter 3. Product overview . . . . . 29

Front . . . . . . . . . . . . . . . . . . . 29

Rear . . . . . . . . . . . . . . . . . . . 30

Chapter 4. Service checkout and

symptom-to-FRU index . . . . . . . . 31

Service checkout . . . . . . . . . . . . . . 31

Problem determination tips . . . . . . . . 31

Symptom-to-FRU index . . . . . . . . . . . 32

Hard disk drive boot error . . . . . . . . . 32

Power supply problems . . . . . . . . . . 33

Beep symptoms . . . . . . . . . . . . . 33

POST error codes . . . . . . . . . . . . 34

Miscellaneous error conditions . . . . . . . 35

Undetermined problems . . . . . . . . . 36

Chapter 5. Troubleshooting,

diagnostics, and recovery . . . . . . . 39

Basic procedure for resolving computer

problems . . . . . . . . . . . . . . . . . 39

Troubleshooting . . . . . . . . . . . . . . 39

Startup problems . . . . . . . . . . . . 40

Audio problems . . . . . . . . . . . . . 41

Network problems . . . . . . . . . . . . 41

Performance problems . . . . . . . . . . 44

Storage drive problems . . . . . . . . . . 45

CD or DVD problems . . . . . . . . . . . 45

Serial connector problems. . . . . . . . . 46

USB device problems . . . . . . . . . . 46

Software problems. . . . . . . . . . . . 47

Diagnostics . . . . . . . . . . . . . . . . 47

Lenovo diagnostic tools. . . . . . . . . . 47

UEFI diagnostic program . . . . . . . . . 47

Recovery . . . . . . . . . . . . . . . . . 48

Restore system files and settings to an earlier

point . . . . . . . . . . . . . . . . . 48

Restore your files from a backup . . . . . . 48

Reset your computer . . . . . . . . . . . 48

Use advanced options . . . . . . . . . . 48

Windows automatic recovery. . . . . . . . 49

Create and use a recovery USB device . . . . 49

Update the device driver . . . . . . . . . 49

Chapter 6. Hardware removal and

installation . . . . . . . . . . . . . . . 51

Handling static-sensitive devices . . . . . . . . 51

Service tool kit . . . . . . . . . . . . . . . 51

Major FRUs and CRUs . . . . . . . . . . . . 52

System board . . . . . . . . . . . . . . . 55

Removing and installing hardware . . . . . . . 56

Vertical stand . . . . . . . . . . . . . . 56

Computer cover . . . . . . . . . . . . . 56

Front bezel . . . . . . . . . . . . . . . 57

Optical drive . . . . . . . . . . . . . . 58

Drive bay assembly . . . . . . . . . . . 60

Hard disk drive . . . . . . . . . . . . . 61

M.2 solid-state drive and heat sink . . . . . 64

M.2 solid-state drive bracket . . . . . . . . 67

Wi-Fi card . . . . . . . . . . . . . . . 67

Front Wi-Fi antenna . . . . . . . . . . . 68

Rear Wi-Fi antenna. . . . . . . . . . . . 68

Memory module . . . . . . . . . . . . . 69

PCI-Express card . . . . . . . . . . . . 70

Coin-cell battery. . . . . . . . . . . . . 71

Power supply assembly . . . . . . . . . . 71

E-lock . . . . . . . . . . . . . . . . . 72

Internal speaker . . . . . . . . . . . . . 73

Illuminated red dot cable . . . . . . . . . 73

Thermal sensor . . . . . . . . . . . . . 74

Front I/O bracket and power button . . . . . 74

Card reader and card reader bracket. . . . . 76

© Copyright Lenovo 2020 i

Heat sink and fan assembly . . . . . . . . 77

Microprocessor . . . . . . . . . . . . . 78

Cover presence switch . . . . . . . . . . 79

System board. . . . . . . . . . . . . . 79

Chapter 7. Notices and

trademarks. . . . . . . . . . . . . . . 81

ii M75s Gen 2 Hardware Maintenance Manual

About this manual

This manual provides service and reference information for ThinkCentre® computers listed on the front cover.

Illustrations in this manual might look different from your product.

Use this manual along with the advanced diagnostic tests to troubleshoot problems.

Important: This manual is intended only for trained service technicians who are familiar with ThinkCentre
computers. Use this manual along with the advanced diagnostic tests to troubleshoot problems effectively.
Before servicing a ThinkCentre computer, be sure to read and understand Chapter 1 “Important safety
information” on page 1.

© Copyright Lenovo 2020 iii

iv M75s Gen 2 Hardware Maintenance Manual

Chapter 1. Important safety information

General safety

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 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.

Attention: Do not attempt to lift any objects that weigh more than 16 kg (35 lb) or objects that you
think are 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 representatives 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, approximately
8 centimeters (3 inches) from the end.

• Do not wear jewelry, chains, metal-frame eyeglasses, or metal fasteners for your clothing.
Remember: 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. Replace any safety device that
is worn or defective.

• Reinstall all covers correctly before returning the machine to the customer.

CAUTION:

Keep fingers and other parts of your body away from hazardous, moving parts. If you suffer an injury,
seek medical care immediately.

CAUTION:

Avoid contact with hot components inside the computer. During operation, some components
become hot enough to burn the skin. Before you open the computer cover, turn off the computer,
disconnect power, and wait approximately 10 minutes for the components to cool.

© Copyright Lenovo 2020 1

Electrical safety

CAUTION:
Electrical current from power, telephone, and communication cables can be hazardous. To avoid
personal injury or equipment damage, disconnect the attached power cords, telecommunication
systems, networks, and modems before you open the computer covers, unless instructed otherwise
in the installation and configuration procedures.

Observe the following rules when working on electrical equipment.

Important: 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.
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
– Removing or installing Field Replaceable Units (FRUs)

• 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.

Remember: Another 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.
Remember: There must be a complete circuit to cause electrical shock. By observing the above rule,
you may prevent a current from passing through your body.

– When using a tester, 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; these instructions are in
the safety sections of maintenance information. Use extreme care when measuring high voltages.

• Regularly 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.

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M75s Gen 2 Hardware Maintenance Manual

• Do not service the following parts with the power on when they are removed from their normal operating
places in a machine:

– Power supply units
– Pumps
– Blowers and fans
– Motor generators
and similar units. (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.

Safety inspection guide

The intent of this inspection guide is to assist you in identifying potentially unsafe conditions on these
products. Each machine, as it was designed and built, had required safety items installed to protect users
and service personnel from injury. This guide addresses only those items. However, good judgment should
be used to identify potential safety hazards due to attachment of 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 CRT face or bulging capacitor

• Mechanical hazards, such as loose or missing hardware

The guide consists of a series of steps presented in a checklist. 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. Power-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 frame ground.
b. The power cord should be the appropriate type as specified in the parts listings.
c. Insulation must not be frayed or worn.

4. Remove the cover.

5. Check for any obvious alterations. Use good judgment as to the safety of any alterations.

6. 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.

7. Check for worn, frayed, or pinched cables.

Chapter 1. Important safety information 3

8. Check that the power-supply cover fasteners (screws or rivets) have not been removed or tampered
with.

Handling electrostatic discharge-sensitive devices

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.

2. Make sure 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 while handling the part.

• 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 the black side of 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 is desirable but not required to protect against ESD damage.
– Attach the ESD ground clip to any frame ground, ground braid, or green-wire ground.

– Use an ESD common ground or reference point when working on a double-insulated or battery-

operated system. 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.

Safety notices (multi-lingual translations)

The caution and danger safety notices in this section are provided in the following languages:

• English

• Arabic

• Brazilian/Portuguese

• Chinese (simplified)

• Chinese (traditional)

• French

• German

• Hebrew

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M75s Gen 2 Hardware Maintenance Manual

• Italian

• Korean

• Spanish

DANGER

Electrical current from power, telephone and communication cables is hazardous.

To avoid a shock hazard:

• Do not connect or disconnect any cables or perform installation, maintenance, or reconfiguration

of this product during an electrical storm.

• Connect all power cords to a properly wired and grounded electrical outlet.

• Connect to properly wired outlets any equipment that will be attached to this product.

• When possible, use one hand only to connect or disconnect signal cables.

• Never turn on any equipment when there is evidence of fire, water, or structural damage.

• Disconnect the attached power cords, telecommunications systems, networks, and modems

before you open the device covers, unless instructed otherwise in the installation and configuration
procedures.

• Connect and disconnect cables as described in the following tables when installing, moving, or

opening covers on this product or attached devices.

To Connect To Disconnect

1. Turn everything OFF.

2. First, attach all cables to devices.

3. Attach signal cables to connectors.

4. Attach power cords to outlet.

5. Turn device ON.

1. Turn everything OFF.

2. First, remove power cords from outlet.

3. Remove signal cables from connectors.

4. Remove all cables from devices.

CAUTION:
When replacing the lithium battery, use only Part Number 45C1566 or an equivalent type battery
recommended by the manufacturer. If your system has a module containing a lithium battery, replace
it only with the same module type made by the same manufacturer. The battery contains lithium and
can explode if not properly used, handled, or disposed of. Do not:

• Throw or immerse into water

• Heat to more than 100°C (212°F)

• Repair or disassemble

Dispose of the battery as required by local ordinances or regulations.

Chapter 1. Important safety information 5

CAUTION:

1

2

When laser products (such as CD-ROMs, DVD-ROM drives, fiber optic devices, or transmitters) are
installed, note the following:

• Do not remove the covers. Removing the covers of the laser product could result in exposure to
hazardous laser radiation. There are no serviceable parts inside the device.

• Use of controls or adjustments or performance of procedures other than those specified herein
might result in hazardous radiation exposure.

DANGER

Some laser products contain an embedded Class 3A or Class 3B laser diode. Note the following:
Laser radiation when open. Do not stare into the beam, do not view directly with optical
instruments, and avoid direct exposure to the beam.

≥18 kg (37 lb) ≥32 kg (70.5 lb) ≥55 kg (121.2 lb)

CAUTION:
Use safe practices when lifting.

CAUTION:
The power control button on the device and the power switch on the power supply do not turn off the
electrical current supplied to the device. The device also might have more than one power cord. To
remove all electrical current from the device, ensure that all power cords are disconnected from the
power source.

6 M75s Gen 2 Hardware Maintenance Manual

Chapter 1. Important safety information 7

≥18 kg (37 lb) ≥32 kg (70.5 lb) ≥55 kg (121.2 lb)

1

2

8 M75s Gen 2 Hardware Maintenance Manual

PERIGO

A corrente elétrica proveniente de cabos de alimentação, de telefone e de comunicações é perigosa.

Para evitar risco de choque elétrico:

• Não conecte nem desconecte nenhum cabo ou execute instalação, manutenção ou reconfiguração deste
produto durante uma tempestade com raios.

• Conecte todos os cabos de alimentação a tomadas elétricas corretamente instaladas e aterradas.

• Todo equipamento que for conectado a este produto deve ser conectado a tomadas corretamente
instaladas.

• Quando possível, utilize apenas uma das mãos para conectar ou desconectar cabos de sinal.

• Nunca ligue nenhum equipamento quando houver evidência de fogo, água ou danos estruturais.

• Antes de abrir tampas de dispositivos, desconecte cabos de alimentação, sistemas de telecomunicação,
redes e modems conectados, a menos que especificado de maneira diferente nos procedimentos de
instalação e configuração.

• Conecte e desconecte os cabos conforme descrito na tabela apresentada a seguir ao instalar, mover ou
abrir tampas deste produto ou de dispositivos conectados.

Para Conectar: Para Desconectar:

1. DESLIGUE Tudo.

2. Primeiramente, conecte todos os cabos aos
dispositivos.

3. Conecte os cabos de sinal aos conectores.

4. Conecte os cabos de alimentação às tomadas.

5. LIGUE os dispositivos.

1. DESLIGUE Tudo.

2. Primeiramente, remova os cabos de alimentação das
tomadas.

3. Remova os cabos de sinal dos conectores.

4. Remova todos os cabos dos dispositivos.

CUIDADO:

Ao substituir a bateria de lítio, utilize apenas uma bateria com Número de Peça 45C1566 ou um tipo de
bateria equivalente recomendado pelo Se o seu sistema possui um módulo com uma bateria de lítio,
substitua-o apenas por um módulo do mesmo tipo e do mesmo fabricante. A bateria contém lítio e
pode explodir se não for utilizada, manuseada ou descartada de maneira correta.

Não:

• Jogue ou coloque na água

• Aqueça a mais de 100°C (212°F)

• Conserte nem desmonte

Descarte a bateria conforme requerido pelas leis ou regulamentos locais.

PRECAUCIÓN:

Chapter 1. Important safety information 9

Quando produtos a laser (como unidades de CD-ROMs, unidades de DVD-ROM, dispositivos de fibra ótica

1

2

ou transmissores) estiverem instalados, observe o seguinte:

• Não remova as tampas. A remoção das tampas de um produto a laser pode resultar em exposição
prejudicial à radiação de laser. Não existem peças que podem ser consertadas no interior do dispositivo.

• A utilização de controles ou ajustes ou a execução de procedimentos diferentes dos especificados aqui
pode resultar em exposição prejudicial à radiação.

PERIGO

Alguns produtos a laser contêm diodo de laser integrado da Classe 3A ou da Classe 3B. Observe o seguinte:

Radiação a laser quando aberto. Não olhe diretamente para o feixe a olho nu ou com instrumentos ópticos e
evite exposição direta ao feixe.

≥18 kg (37 lb) ≥32 kg (70.5 lb) ≥55 kg (121.2 lb)

CUIDADO:

Utilize procedimentos de segurança para levantar equipamentos.

CUIDADO:

O botão de controle de alimentação do dispositivo e o botão para ligar/desligar da fonte de alimentação não
desligam a corrente elétrica fornecida ao dispositivo. O dispositivo também pode ter mais de um cabo de
alimentação. Para remover toda a corrente elétrica do dispositivo, assegure que todos os cabos de
alimentação estejam desconectados da fonte de alimentação.

10 M75s Gen 2 Hardware Maintenance Manual

Chapter 1. Important safety information 11

1

2

12 M75s Gen 2 Hardware Maintenance Manual

Chapter 1. Important safety information 13

1

2

DANGER

Le courant électrique provenant de l'alimentation, du téléphone et des câbles de transmission peut présenter
un danger.

Pour éviter tout risque de choc électrique :

• Ne manipulez aucun câble et n'effectuez aucune opération d'installation, d'entretien ou de reconfiguration
de ce produit au cours d'un orage.

• Branchez tous les cordons d'alimentation sur un socle de prise de courant correctement câblé et mis à la
terre.

• Branchez sur des socles de prise de courant correctement câblés tout équipement connecté à ce produit.

• Lorsque cela est possible, n'utilisez qu'une seule main pour connecter ou déconnecter les câbles
d'interface.

• Ne mettez jamais un équipement sous tension en cas d'incendie ou d'inondation, ou en présence de
dommages matériels.

• Avant de retirer les carters de l'unité, mettez celle-ci hors tension et déconnectez ses cordons
d'alimentation, ainsi que les câbles qui la relient aux réseaux, aux systèmes de télécommunication et aux
modems (sauf instruction contraire mentionnée dans les procédures d'installation et de configuration).

• Lorsque vous installez, que vous déplacez, ou que vous manipulez le présent produit ou des
périphériques qui lui sont raccordés, reportez-vous aux instructions ci-dessous pour connecter et
déconnecter les différents cordons.

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M75s Gen 2 Hardware Maintenance Manual

Connexion Déconnexion

1. Mettez les unités HORS TENSION.

2. Commencez par brancher tous les cordons sur les
unités.

3. Branchez les câbles d'interface sur des
connecteurs.

4. Branchez les cordons d'alimentation sur des prises.

5. Mettez les unités SOUS TENSION.

1. Mettez les unités HORS TENSION.

2. Débranchez les cordons d'alimentation des prises.

3. Débranchez les câbles d'interface des connecteurs.

4. Débranchez tous les câbles des unités.

ATTENTION:

Remplacer la pile au lithium usagée par une pile de référence identique exclusivement, (référence
45C1566), ou suivre les instructions du fabricant qui en définit les équivalences. Si votre système est
doté d'un module contenant une pile au lithium, vous devez le remplacer uniquement par un module
identique, produit par le même fabricant. La pile contient du lithium et peut exploser en cas de
mauvaise utilisation, de mauvaise manipulation ou de mise au rebut inappropriée.

Ne pas :

• la jeter à l'eau,

• l'exposer à des températures supérieures à 100°C,

• chercher à la réparer ou à la démonter.

Ne pas mettre la pile à la poubelle. Pour la mise au rebut, se reporter à la réglementation en vigueur.

ATTENTION:

Si des produits à laser (tels que des unités de CD-ROM, de DVD-ROM, des unités à fibres optiques, ou
des émetteurs) sont installés, prenez connaissance des informations suivantes :

• Ne retirez pas le carter. En ouvrant l'unité de CD-ROM ou de DVD-ROM, vous vous exposez au

rayonnement dangereux du laser. Aucune pièce de l'unité n'est réparable.

• Pour éviter tout risque d'exposition au rayon laser, respectez les consignes de réglage et

d'utilisation des commandes, ainsi que les procédures décrites dans le présent manuel.

DANGER

Certains produits à laser contiennent une diode à laser intégrée de classe 3A ou 3B. Prenez
connaissance des informations suivantes:

Rayonnement laser lorsque le carter est ouvert. Evitez toute expositiondirecte au rayon laser. Evitez
de regarder fixement le faisceau ou del'observer à l'aide d'instruments optiques.

Chapter 1. Important safety information 15

≥18 kg (37 lb) ≥32 kg (70.5 lb) ≥55 kg (121.2 lb)

1

2

ATTENTION:

Soulevez la machine avec précaution.

ATTENTION:

L'interrupteur de contrôle d'alimentation de l'unité et l'interrupteur dubloc d'alimentation ne coupent
pas le courant électrique alimentantl'unité. En outre, le système peut être équipé de plusieurs
cordonsd'alimentation. Pour mettre l'unité hors tension, vous devez déconnectertous les cordons de
la source d'alimentation.

VORSICHT

An Netz-, Telefon- und Datenleitungen können gefährliche Spannungen anliegen.

Aus Sicherheitsgründen:

• Bei Gewitter an diesem Gerät keine Kabel anschließen oder lösen. Ferner keine Installations-,

Wartungs- oder Rekonfigurationsarbeiten durchführen.

• Gerät nur an eine Schutzkontaktsteckdose mit ordnungsgemäß geerdetem Schutzkontakt

anschließen.

• Alle angeschlossenen Geräte ebenfalls an Schutzkontaktsteckdosen mit ordnungsgemäß

geerdetem Schutzkontakt anschließen.

• Die Signalkabel nach Möglichkeit einhändig anschließen oder lösen, um einen Stromschlag durch

Berühren von Oberflächen mit unterschiedlichem elektrischem Potenzial zu vermeiden.

• Geräte niemals einschalten, wenn Hinweise auf Feuer, Wasser oder Gebäudeschäden vorliegen.

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M75s Gen 2 Hardware Maintenance Manual

• Die Verbindung zu den angeschlossenen Netzkabeln, Telekommunikationssystemen, Netzwerken

und Modems ist vor dem Öffnen des Gehäuses zu unterbrechen, sofern in den Installations- und
Konfigurationsprozeduren keine anders lautenden Anweisungen enthalten sind.

• Zum Installieren, Transportieren und Öffnen der Abdeckungen des Computers oder der

angeschlossenen Einheiten die Kabel gemäß der folgenden Tabelle anschließen und abziehen.

Zum Anschließen der Kabel gehen Sie wie folgt vor Zum Abziehen der Kabel gehen Sie wie folgt vor

1. Schalten Sie alle Einheiten AUS.

2. Schließen Sie erst alle Kabel an die Einheiten an.

3. Schließen Sie die Signalkabel an die Buchsen an.

4. Schließen Sie die Netzkabel an die Steckdose an.

5. Schalten Sie die Einheit EIN.

1. Schalten Sie alle Einheiten AUS.

2. Ziehen Sie zuerst alle Netzkabel aus den
Netzsteckdosen.

3. Ziehen Sie die Signalkabel aus den Buchsen.

4. Ziehen Sie alle Kabel von den Einheiten ab.

CAUTION:

Eine verbrauchte Lithiumbatterie nur durch eine Batterie mit der Teilenummer 45C1566 oder eine
gleichwertige, vom Hersteller empfohlene Batterie ersetzen. Enthält das System ein Modul mit einer
Lithiumbatterie, dieses nur durch ein Modul desselben Typs und von demselben Hersteller ersetzen. Die
Batterie enthält Lithium und kann bei unsachgemäßer Verwendung, Handhabung oder Entsorgung
explodieren.

Die Batterie nicht:

• mit Wasser in Berührung bringen.

• über 100 C erhitzen.

• reparieren oder zerlegen.

Die örtlichen Bestimmungen für die Entsorgung von Sondermüll beachten.

ACHTUNG:

Bei der Installation von Lasergeräten (wie CD-ROM-Laufwerken, DVD- aufwerken, Einheiten mit
Lichtwellenleitertechnik oder Sendern) Folgendes beachten:

• Die Abdeckungen nicht entfernen. Durch Entfernen der Abdeckungen des Lasergeräts können

gefährliche Laserstrahlungen freigesetzt werden. Das Gerät enthält keine zu wartenden Teile.

• Werden Steuerelemente, Einstellungen oder Durchführungen von Prozeduren anders als hier

angegeben verwendet, kann gefährliche Laserstrahlung auftreten.

VORSICHT

Einige Lasergeräte enthalten eine Laserdiode der Klasse 3A oder 3B. Beachten Sie Folgendes:

Chapter 1. Important safety information 17

Laserstrahlung bei geöffneter Verkleidung. Nicht in den Strahl blicken. Keine Lupen oder Spiegel

1

2

verwenden. Strahlungsbereich meiden.

≥18 kg ≥32 kg ≥55 kg

ACHTUNG:

Arbeitsschutzrichtlinien beim Anheben der Maschine beachten.

ACHTUNG:

Mit dem Netzschalter an der Einheit und am Netzteil wird die Stromversorgung für die Einheit nicht
unterbrochen. Die Einheit kann auch mit mehreren Netzkabeln ausgestattet sein. Um die
Stromversorgung für die Einheit vollständig zu unterbrechen, müssen alle zum Gerät führenden
Netzkabel vom Netz getrennt werden.

18 M75s Gen 2 Hardware Maintenance Manual

Chapter 1. Important safety information 19

1

2

PERICOLO

La corrente elettrica proveniente dai cavi di alimentazione, del telefono e di comunicazione può essere
pericolosa.

Per evitare il rischio di scosse elettriche:

20

M75s Gen 2 Hardware Maintenance Manual

• Non collegare o scollegare qualsiasi cavo oppure effettuare l'installazione, la manutenzione o la

riconfigurazione del prodotto durante un temporale.

• Collegare tutti i fili elettrici a una presa di alimentazione correttamente cablata e dotata di messa a

terra.

• Collegare alle prese elettriche appropriate tutte le apparecchiature che verranno utilizzate per

questo prodotto.

• Se possibile, utilizzare solo una mano per collegare o scollegare i cavi di segnale.

• Non accendere assolutamente apparecchiature in presenza di incendi, perdite d'acqua o danno

strutturale.

• Scollegare i cavi di alimentazione, i sistemi di telecomunicazione, le reti e il modem prima di aprire i

coperchi del dispositivo, salvo istruzioni contrarie relative alle procedure di installazione e
configurazione.

• Collegare e scollegare i cavi come descritto nella seguente tabella quando vengono effettuate

operazioni di installazione, spostamento o apertura dei coperchi di questo prodotto o delle unità
collegate.

Per collegarsi Per scollegarsi

1. SPEGNERE le apparecchiature.

2. Innanzitutto, collegare tutti i cavi alle unità.

3. Collegare i cavi di segnale ai connettori.

4. Collegare i cavi di alimentazione alla presa.

5. Accendere l'unità.

1. SPEGNERE le apparecchiature.

2. Innanzitutto, rimuovere i cavi di alimentazione dalla
presa.

3. Rimuovere i cavi di segnale dai connettori.

4. Rimuovere tutti i cavi dalle unità.

ATTENZIONE:

Quando si sostituisce la batteria al litio, utilizzare solo il Numero parte 45C1566 o un tipo di batteria
equivalente consigliato dal produttore. Se sul sistema è presente un modulo che contiene una batteria
al litio, sostituirlo solo con un tipo di modulo dello stesso tipo della stessa casa di produzione. La
batteria contiene litio e può esplodere se usata, maneggiata o smaltita in modo non corretto.

Non:

• Gettare o immergere la batteria nell'acqua

• Riscaldarla ad una temperatura superiore ai 100 gradi C (212 gradi F)

• Smontarla, ricaricarla o tentare di ripararla

Le batterie usate vanno smaltite in accordo alla normativa in vigore (DPR 915/82 e successive
disposizioni e disposizioni locali).

ATTENZIONE:

Quando vengono installati prodotti laser (quali CD-ROM, unità DVD-ROM, unità a fibre ottiche o
trasmittenti), tener presente quanto segue:

Chapter 1. Important safety information 21

• Non rimuovere gli sportelli. L'apertura di un'unità laser può determinare l'esposizione a radiazioni

1

2

laser pericolose. All'interno dell'unità non vi sono parti su cui effettuare l'assistenza tecnica.

• L'utilizzo di controlli, regolazioni o l'esecuzione di procedure non descritti nel presente manuale

possono provocare l'esposizione a radiazioni pericolose.

PERICOLO

Alcune unità laser contengono un diodo laser di Classe 3A o Classe 3B. Tener presente quanto segue:

Aprendo l'unità vengono emesse radiazioni laser. Non fissare il fascio, non guardarlo direttamente
con strumenti ottici ed evitare l'esposizione al fascio.

≥18 kg ≥32 kg ≥55 kg

ATTENZIONE:

Prestare attenzione nel sollevare l'apparecchiatura.

ATTENZIONE:

Il pulsante di controllo dell'alimentazione presente sull'unità e l'interruttore dell'alimentatore non
disattivano l'alimentazione corrente fornita all'unità. E' possibile che l'unità disponga di più cavi di
alimentazione. Per disattivare l'alimentazione dall'unità, accertarsi che tutti i cavi di alimentazione
siano scollegati dalla fonte di alimentazione.

22 M75s Gen 2 Hardware Maintenance Manual

Chapter 1. Important safety information 23

1

2

PELIGRO

La corriente eléctrica procedente de cables de alimentación, teléfonos y cables de comunicación puede ser
peligrosa.

Para evitar el riesgo de descarga eléctrica:

• No conecte ni desconecte los cables ni realice ninguna tarea de instalación, mantenimiento o

reconfiguración de este producto durante una tormenta eléctrica.

• Conecte todos los cables de alimentación a tomas de corriente debidamente cableadas y

conectadas a tierra.

• Cualquier equipo que se conecte a este producto también debe conectarse a tomas de corriente

debidamente cableadas.

• Siempre que sea posible, utilice una sola mano para conectar o desconectar los cables de señal.

24

M75s Gen 2 Hardware Maintenance Manual

• No encienda nunca un equipo cuando hay señales de fuego, agua o daños estructurales.

• Desconecte los cables de alimentación, los sistemas de telecomunicaciones, las redes y los

módems conectados antes de abrir las cubiertas de los dispositivos, a menos que se indique lo
contrario en los procedimientos de instalación y configuración.

• Conecte y desconecte los cables, como se describe en la tabla siguiente, cuando instale, mueva o

abra las cubiertas de este producto o de los dispositivos conectados.

Para conectar Para desconectar

1. APÁGUELO todo.

2. En primer lugar, conecte todos los cables a los
dispositivos.

3. Conecte los cables de señal a los conectores.

4. Enchufe los cables de alimentación a las tomas de
corriente.

5. Encienda el dispositivo.

1. APÁGUELO todo.

2. En primer lugar, desenchufe los cables de
alimentación de las tomas de corriente.

3. Desconecte los cables de señal de los conectores.

4. Desconecte todos los cables de los dispositivos.

PRECAUCIÓN:

Cuando sustituya una batería de litio, utilice solamente una batería número de pieza 45C1566 u otra
de tipo equivalente recomendada por el fabricante. Si su sistema dispone de un módulo que contiene
una batería de litio, reemplácelo sólo con el mismo tipo de módulo, del mismo fabricante. La batería
contiene litio y puede explotar si no se utiliza, manipula o desecha correctamente.

No debe:

• Arrojarla al agua o sumergirla en ella

• Exponerla a temperaturas superiores a 100°C (212°F)

• Repararla o desmontarla

Deshágase de la batería según especifiquen las leyes o normas locales.

PRECAUCIÓN:

Cuando haya productos láser (como unidades de CD-ROM, unidades de DVD, dispositivos de fibra
óptica o transmisores) instalados, tenga en cuenta lo siguiente:

• No quite las cubiertas. Si quita las cubiertas del producto láser, podría quedar expuesto a radiación

láser peligrosa. Dentro del dispositivo no existe ninguna pieza que requiera servicio técnico.

• Si usa controles o ajustes o realiza procedimientos que no sean los especificados aquí, podría

exponerse a radiaciones peligrosas.

PELIGRO

Chapter 1. Important safety information 25

Algunos productos láser tienen incorporado un diodo láser de clase 3A o clase 3B. Tenga en cuenta lo

1

2

siguiente:

Cuando se abre, queda expuesto a radiación láser. No mire directamente al rayo láser, ni siquiera con
instrumentos ópticos, y evite exponerse directamente al rayo láser.

≥18 kg ≥32 kg ≥55 kg

PRECAUCIÓN:

Adopte procedimientos seguros al levantar el equipo.

PRECAUCIÓN:

El botón de control de alimentación del dispositivo y el interruptor de alimentación de la fuente de
alimentación no desconectan la corriente eléctrica suministrada al dispositivo. Además, el dispositivo
podría tener más de un cable de alimentación. Para suprimir toda la corriente eléctrica del dispositivo,
asegúrese de que todos los cables de alimentación estén desconectados de la toma de corriente.

26 M75s Gen 2 Hardware Maintenance Manual

Chapter 2. Important service information

Strategy for replacing FRUs

Before replacing parts:

Ensure that all software fixes, drivers, and UEFI BIOS downloads are installed before you replace any FRUs
listed in this manual.

After a system board is replaced, ensure that the latest UEFI BIOS is loaded to the system board before you
complete the service action.

To download and install software fixes, drivers, and UEFI BIOS, go to
the instructions on the screen.

Use the following strategy to prevent unnecessary expense for replacing and servicing FRUs:

• If you are instructed to replace a FRU but the replacement does not correct the problem, reinstall the
original FRU before you continue.

• Some computers have both a processor board and a system board. If you are instructed to replace either
the processor board or the system board, and replacing one of them does not correct the problem,
reinstall that board, and then replace the other one.

• If an adapter or a device consists of more than one FRU, any of the FRUs might be the cause of the error.
Before replacing the adapter or device, remove the FRUs, one by one, to see if the symptoms change.
Replace only the FRU that changed the symptoms.

https://pcsupport.lenovo.com and follow

Strategy for replacing a hard disk drive or a solid-state drive

Always try to run a low-level format operation before replacing a hard disk drive or a solid-state drive. This
will cause all customer data on the drive to be lost. Ensure that the customer has a current backup of the
data before you perform this task.

Attention: The drive startup sequence in the computer you are servicing might have been changed. Be
extremely careful during write operations such as copying, saving, or formatting. If you select an incorrect
drive, data or programs can be overwritten.

Important notice for replacing a system board

Some components mounted on a system board are very sensitive. Improper handling of a system board can
cause damage to those components, and may cause a system malfunction.

After replacing the system board, use the Golden Key U1 tool to bind the model type, serial number, and
Brand ID of the computer with the new system board. Refer to

ht507251

Attention: When handling a system board:

• Do not drop a system board or apply any excessive force to it.

• Avoid rough handling of any kind.

• Avoid bending a system board and hard pushing to prevent cracking at each Ball Grid Array (BGA)

© Copyright Lenovo 2020 27

for instructions.

chipset.

https://support.lenovo.com/us/en/solutions/

How to use error codes

Use the error codes displayed on the screen to diagnose failures. If more than one error code is displayed,
begin the diagnosis with the first error code. Whatever causes the first error code might also cause false error
codes. If no error code is displayed, see whether the error symptom is listed in the “Symptom-to-FRU Index”
section.

Strategy for replacing FRUs for CTO, special-bid, and standard models

This topic provides information about the model types and FRU identification.

Product definition

This topic introduces different model types and how to identify each type.

Dynamic Configure To Order (CTO) model

This model provides the ability for a customer to configure a Lenovo solution from a Web site, and have this
configuration sent to fulfillment, where it is built and shipped directly to the customer. The machine label and
eSupport will load these products as the 4-character MT, 4-character model, and 2-character country code.
The model is “CTO1” and the default country code is “WW” (example: 20AACTO1WW).

Special-bid model

This model is a unique configuration that has been negotiated between Lenovo and the customer. A unique
MTM consists of a 4-character MT, a 4-character model, and a numeric 2-character country code is provided
to the customer to place orders (example: 20AA000955). The country code assigned is numeric and does not
designate a specific country or region. The custom model factsheet for the MTM indicates which country the
special-bid MTM is set up for. Special-bid offering is not generally announced.

Standard model

Standard models (fixed configuration) are announced and offered to all customers. The MTM portion of the
machine label consists of a 4-character MT, a 4-character model, and an alphabetic 2-character country
code. The country code assigned is alphabetic and represents a designated country or region (example:
20AA0009UK).

FRU identification

To identify FRUs for a product, do the following:

1. Go to:

2. Type the Machine Type in the corresponding field to get a general FRU list, or type the Serial Number for

https://support.lenovo.com/partslookup

more detailed FRU information.

28

M75s Gen 2 Hardware Maintenance Manual

Chapter 3. Product overview

Front

1. Optical drive eject button* 2. Optical drive activity indicator*

3. SD-card slot*

5. Storage drive activity indicator 6. ThinkCentre

7. Microphone connector 8. Headset connector

9. USB-C

11. USB 3.2 connectors Gen 2

™

(3.2 Gen 1) connector 10. USB 3.2 connectors Gen 1

4. Power button

®

LED

12. Internal speaker

* for selected models

© Copyright Lenovo 2020 29

Rear

1. Audio line-out connector 2. DisplayPort® out connectors

3. HDMI

5. USB 2.0 connector (with smart power-on) 6. Security-lock slot

7. Serial connector 8. Ethernet connector

9. Padlock loop 10. E-lock slots

11. PCI-Express card area 12. Power cord connector

™

out connector

4. USB 2.0 connectors

30 M75s Gen 2 Hardware Maintenance Manual

Chapter 4. Service checkout and symptom-to-FRU index

This chapter provides information about general service checkout and symptom-to-FRU index.

Service checkout

Attention: The drives in the computer you are servicing might have been rearranged or the drive startup

sequence changed. Be extremely careful during write operations such as copying, saving, or formatting.
Data or programs can be overwritten if you select an incorrect drive.

General error messages appear if a problem or conflict is found by a program, the operating system, or both.
For an explanation of these messages, refer to the information supplied with that software package.

Use the following procedure to help determine the cause of the problem:

1. Turn off the computer and all external devices.

2. Check all cables and power cords.

3. Set all display controls to the middle position.

4. Turn on all external devices.

5. Turn on the computer.

• Look for displayed error codes.

• Listen for beep codes.

• Look for readable instructions or a main menu on the display.
If you did not receive the correct response, proceed to step 6 on page 31.
If you do receive the correct response, proceed to step 7 on page 31.

6. Look at the following conditions and follow the instructions:

• If you hear beep codes during POST, go to “Beep symptoms” on page 33.

• If the computer displays a POST error, go to “POST error codes” on page 34.

• If the computer hangs and no error is displayed, continue at step 7 on page 31.

7. Run the Diagnostic programs. See “Diagnostics” on page 47.

• If you receive an error, replace the part that the diagnostic program calls out.

• If the test stops and you cannot continue, replace the last device tested.

Problem determination tips

Due to the variety of hardware and software combinations that can be encountered, use the following
information to assist you in problem determination. If possible, have this information available when
requesting assistance from Service Support and Engineering functions.

• Machine type and model

• Processor or hard disk drive upgrades

• Failure symptom
– Do diagnostics indicate a failure?

– What, when, where, single, or multiple systems?
– Is the failure repeatable?
– Has this configuration ever worked?

© Copyright Lenovo 2020 31

– If it has been working, what changes were made prior to its failing?
– Is this the original reported failure?

• Diagnostics version
– Type and version level

• Hardware configuration
– Print (print screen) configuration currently in use

– BIOS level

• Operating system software
– Type and version level

Notes: To eliminate confusion, identical systems are considered identical only if they:

1. Are the exact machine type and models

2. Have the same BIOS level

3. Have the same adapters/attachments in the same locations

4. Have the same address jumpers/terminators/cabling

5. Have the same software versions and levels

6. Have the same Diagnostic Diskettes (version)

7. Have the same configuration options set in the system

8. Have the same setup for the operating system control files

Comparing the configuration and software set-up between “working and non-working” systems will often
lead to problem resolution.

Symptom-to-FRU index

The Symptom-to-FRU index lists error symptoms and possible causes. The most likely cause is listed first.
Always begin with “Symptom-to-FRU index” on page 32. This index can also be used to help you decide
which FRUs to have available when servicing a computer. If you are unable to correct the problem using this
index, go to “Undetermined problems” on page 36.

Notes:

• The Symptom-to-FRU index is not specific to any machine type and are applicable to all computers.

• If you have both an error message and an incorrect audio response, diagnose the error message first.

• If you cannot run the diagnostic tests or you get a diagnostic error code when running a test, but did receive a
POST error message, diagnose the POST error message first.

• If you did not receive any error message, look for a description of your error symptoms in the first part of this index.

Hard disk drive boot error

A hard disk drive boot error can have the following causes.

Error FRU/Action

The start-up drive is not in the boot sequence in
configuration.

Check the configuration and ensure that the start-up drive
is in the boot sequence.

No operating system installed on the boot drive. Install an operating system on the boot drive.

32 M75s Gen 2 Hardware Maintenance Manual

Error FRU/Action

The boot sector on the startup drive is corrupted. The drive must be formatted. Do the following:

1. Attempt to back up the data on the failing hard disk
drive.

2. Using the operating system programs, format the
hard disk drive.

The drive is defective. Replace the hard disk drive.

Power supply problems

If you suspect a power problem, use the following procedures.

Check/Verify

Check the following for proper installation.

• Power cord

• On/Off switch connector

• On/Off switch power supply connector

• System board power supply connectors

• Microprocessor connection

Check the power cord for continuity.

Check the power-on switch for continuity. Power-on switch

FRU/Action

Reseat connectors

Power cord

Beep symptoms

Beep symptoms are tones or a series of tones separated by pauses (intervals without sound) during POST.

The following table describes the beep symptoms.

Beep symptom

2 short beeps: common POST error Common POST error code. See the detailed failure

3 short and 1 long beeps: DRAM memory error Perform the following actions in order:

FRU/Action

information in “POST error codes” on page 34.

1. Make sure that the memory modules are properly
seated in the memory slots.

2. Replace the memory modules.

3. Replace the system board (for trained service
personnel only).

4 long beeps: insufficient shadow RAM resources for
option ROM (error code: 8998) or PCIe/PCI MMIO
(memory mapped input/output) resources (error code:

8999)

2 long and 3 short beeps: graphics card error Perform the following actions in order:

See the detailed failure information in “POST error codes”
on page 34.

1. Make sure that the graphics cards are properly
seated in the slots.

2. Replace the graphics cards.

3. Replace the system board (for trained service
personnel only).

Chapter 4. Service checkout and symptom-to-FRU index 33

POST error codes

Each time you turn on the system, it performs a series of tests that check the operation of the system and
some options. This series of tests are called the Power-On Self-Test, or POST. POST checks the following
operations:

• Some basic system-board operations

• Memory operation

• Video operation

• Whether the boot drive is working

If the POST detects a problem, an error message appears on the screen. A single problem might cause
several error messages to appear. When you correct the cause of the first error message, the other error
messages probably will not appear on the screen the next time.

Error code

0135

0211 Keyboard not found This error message is displayed when

0164 Memory configuration change has

1762

1820 More than one external fingerprint

POST error message Description/Action

CPU fan failure
System fan failure
Power fan failure
Front fan failure
Rear fan failure
Auxiliary fan failure
ODD fan failure

occurred

Storage device configuration change
has occurred

reader is attached. Turn off and
remove all but the reader that you set
up within your main operating
system.

This error message is displayed
when a fan fails and the system
might be overheating.

Press F1 to enter Setup, F2 to
resume.

no keyboard is detected.

This error message is displayed
when the memory configuration is
changed.

Press F1 to enter Setup, F2 to
resume.

This error message is displayed
when a hard disk drive change or
an optical drive change has been
made.

Press F1 to enter Setup, F2 to
resume.

This error message is displayed
when more than one external
fingerprint reader is connected to
the computer.

Turn off and remove all but the
reader that you set up within your
main operating system.

34 M75s Gen 2 Hardware Maintenance Manual

Miscellaneous error conditions

Message/Symptom

Changing display colors Display/Monitor

Computer will not power-off. See “Hard disk drive boot
error” on page 32.

Computer will not RPL from server

Computer will not perform a Wake On LAN

®

(if applicable)

FRU/Action

1. Power Switch

2. System Board

3. Riser card, if installed.

1. Ensure that the network is in startup sequence as the
first device or the first device after diskette.

2. Ensure that the network adapter is enabled for RPL.

3. Network adapter (Advise network administrator of
new MAC address)

1. Check the power supply and signal cable
connections to the network adapter.

2. Ensure that the operating system settings are set to
enable Wake on LAN.

3. Ensure that the Wake On LAN feature is enabled in
Setup/Configuration.

4. Ensure that the network administrator is using the
correct MAC address.

5. Ensure no interrupt or I/O address conflicts.

6. Network adapter (advise network administrator of
new MAC address)

Dead computer. See “Hard disk drive boot error” on page

32.

Diskette drive in-use light remains on or does not light
when drive is active.

Blank screen except for flashing cursor.

Incorrect memory size during POST

"Insert a Diskette" icon appears with a known-good
diagnostics diskette in the first 3.5-inch diskette drive.

Intensity or color varies from left to right of characters and
color bars

1. Power Supply

2. System Board

1. Diskette Drive

2. System Board

3. Diskette Drive Cable

1. System Board

2. Primary Hard Disk Drive

3. Hard Disk Drive Cable

1. Run the Memory tests.

2. Memory Module

3. System Board

1. System Board

2. Diskette Drive Cable

3. Network Adapter

1. Display

2. Video adapter (if present)

3. System Board

No power or fan not running

1. See “Hard disk drive boot error” on page 32.

Chapter 4. Service checkout and symptom-to-FRU index 35

Message/Symptom

Non-system disk or disk error-type message with a
known-good diagnostic diskette.

Other display symptoms not listed above (including blank
or illegible display)

FRU/Action

1. Diskette Drive

2. System Board

3. Diskette Drive Cable

1. Display

2. System Board

Power-on indicator or hard disk drive in-use light not on,
but computer works correctly

Printer problems

Program loads from the hard disk with a known-good
diagnostics diskette in the first 3.5-inch diskette drive

RPL computer cannot access programs from its own hard
disk.

RPL computer does not RPL from server

Serial or parallel connector device failure (system board
connector)

1. Power switch/LED assembly

2. System Board

1. Printer

2. System Board

1. Run the Setup Utility program and check the Startup
sequence.

2. Diskette Drive

3. Diskette Drive Cable

4. System Board

5. Power Supply

1. If the network administrator is using LCCM Hybrid
RPL, check the startup sequence:

a. First device - network
b. Second device - hard disk

2. Hard disk drive

1. Check the startup sequence.

2. Check the network adapter LED status.

1. External Device Self-Test OK?

2. External Device

3. Cable

4. System Board

Serial or parallel connector device failure (adapter
connector)

Some or all keys on the keyboard do not work

1. External Device Self-Test OK?

2. External Device

3. Cable

4. Alternate Adapter

5. System Board

1. Keyboard

2. Keyboard Cable

3. System Board

Undetermined problems

This section provides instructions on how to find out the failing devices or adapters.

1. Turn off the computer.

36

M75s Gen 2 Hardware Maintenance Manual

2. Remove or disconnect the following components (if installed) one at a time.
a. External devices (modem, printer, or mouse)
b. Any adapters
c. Memory modules
d. Extended video memory
e. External Cache
f. External Cache RAM
g. Hard disk drive
h. Diskette drive

3. Turn on the computer to retest the system.

4. Repeat steps 1 through 3 until you find the failing device or adapter.

If all devices and adapters have been removed, and the problem continues, replace the system board. See
“System board” on page 79.

Chapter 4. Service checkout and symptom-to-FRU index 37

38 M75s Gen 2 Hardware Maintenance Manual

Chapter 5. Troubleshooting, diagnostics, and recovery

This chapter provides solutions to resolve computer problems. Use the basic procedure as a starting point
for resolving computer problems.

Basic procedure for resolving computer problems

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

1. Check that:
a. The cables for all connected devices are connected correctly and securely.
b. All components have been reassembled correctly.
c. All connected devices that require ac power are connected to properly grounded and working

electrical outlets.

d. All connected devices are enabled in UEFI BIOS.

2. Use an antivirus program to see if the computer has been infected by a virus. If the program detects a
virus, remove the virus.

3. Go to “Troubleshooting” on page 39 and follow the instructions for the type of problem you are
experiencing.

4. Run the diagnostic program. See “Diagnostics” on page 47.

5. Recover your operating system. See “Recovery” on page 48.

6. If the problem persists, contact Lenovo.

Troubleshooting

Use the troubleshooting information to find solutions to problems that have definite symptoms.

© Copyright Lenovo 2020 39

Startup problems

Problem Solution

• Ensure that the power cord is correctly connected to the rear of the
computer and to a working electrical outlet.

The computer does not start up when you
press the power button.

The operating system does not start up from
the correct storage drive or fails to start up

• If the computer has a secondary power switch on the rear of the
computer, ensure that it is switched on.

• The power indicator on the front of the computer is on.

• The computer voltage matches the voltage available at the
electrical outlet for your country or region.

• Ensure that all storage drive signal cables and power cables are
connected correctly.

• Ensure that the storage drive the computer starts up from is listed
as the first startup device in UEFI BIOS.

• In rare cases, the storage drive with the operating system might get
corrupted or damaged. In such cases, you might need to replace
the storage drive.

• If the computer is installed with an Optane memory:
– Ensure that the Optane memory is not removed.

– Ensure that the Optane memory is not damaged. Check the

Optane memory using diagnostic tools.

The computer beeps multiple times before
the operating system starts up.

Ensure that no keys are stuck.

40 M75s Gen 2 Hardware Maintenance Manual

Audio problems

Problem Solution

• If you are using powered external speakers that have an On/Off

control, ensure that:
– The On/Off control is set to the On position.

– The speaker power cable is connected to a properly grounded,

• If your external speakers have a volume control, ensure that the

volume is not set too low.

• Click the volume icon in the Windows notification area on the

taskbar. Check the speaker and volume settings. Do not mute the
speaker or set the volume at a very low level.

• If your computer has a front audio panel, ensure that the volume is

not set too low.

The audio cannot be heard on the Windows
operating system.

®

• Ensure that your external speakers (and headphones, if used) are

connected to the correct audio connector on the computer. Most
speaker cables are color-coded to match the audio connector.

Note: When external-speaker or headphone cables are connected
to the audio connector, the internal speaker, if present, is disabled.
In most cases, if an audio adapter is installed in one of the
expansion slots, the audio function built into the system board is
disabled. Therefore, you must use the audio connectors on the
audio adapter.

• Ensure that the program you are running is designed for use in the

Microsoft Windows operating system. If the program is designed to
run in DOS, the program does not use the Windows sound feature.
The program must be configured to use SoundBlaster Pro or
SoundBlaster emulation.

• Ensure that the audio device drivers are correctly installed.

functional ac electrical outlet.

The sound does not come from the headset
or headphones.

The sound comes from one of the external
speakers.

Select the headset or headphones as the default audio output device
in advanced sound settings.

• Ensure that the speaker cable is inserted completely into the

connector on the computer.

• Ensure that the cable that connects the left speaker to the right

speaker is securely connected.

• Ensure that the balance settings are set correctly.

1. Right-click the volume icon in the Windows notification area
on the taskbar. Then, click Open Volume Mixer and select the
desired speaker.

2. Click the speaker icon on top of the volume control, and then
click the Levels tab.

Network problems

Note: The Wi-Fi® and Bluetooth features are optional.

Chapter 5. Troubleshooting, diagnostics, and recovery 41

Problem Solution

• Connect the cable from the Ethernet connector to the RJ45
connector of the hub.

• Enable the Ethernet LAN feature in UEFI BIOS.

• Enable the Ethernet LAN adapter.

1. Go to Control Panel and view by large icons or small icons.

2. Click Network and Sharing Center ➙ Change adapter

The computer cannot connect to an Ethernet
LAN.

When a Gigabit Ethernet model computer is
used at a speed of 1000 Mbps, the Ethernet
LAN connection fails or errors occur.

The Wake On LAN (WOL) feature does not
work.

3. Right-click the Ethernet LAN adapter icon and click Enable.

• Update or reinstall the Ethernet LAN driver.

• Install all networking software that is necessary for your network
environment. Check with your LAN administrator for the necessary
networking software.

• Set the same duplex for the switch port and the adapter. If you
configured the adapter for full duplex, ensure that the switch port is
also configured for full duplex. Setting a wrong duplex mode might
degrade performance, cause data loss, or result in lost
connections.

Connect the network cable to the Ethernet connector using Category
5 wiring and a 100 BASE-T hub/switch (not 100 BASE-X).

Enable the Wake On LAN feature in UEFI BIOS.

settings.

The Wi-Fi feature does not work.

• Enable the Wi-Fi feature in UEFI BIOS.

• Enable all Wi-Fi devices.

1. Right-click the Start button to open the Start context menu.

2. Click Device Manager. Type the administrator password or
provide confirmation, if prompted.

3. Expand Network adapters to display all network devices.

4. Right-click each Wi-Fi device, and then click Enable device.

• Enable the Wi-Fi feature in Windows Settings.

1. Open the Start menu.

2. Click Settings ➙ Network & Internet ➙ Wi-Fi.

3. Enable the Wi-Fi feature.

• Update or reinstall the Wi-Fi driver.

42 M75s Gen 2 Hardware Maintenance Manual

Problem Solution

• Enable the Bluetooth feature in UEFI BIOS.

• Enable all Bluetooth devices.

1. Right-click the Start button to open the Start context menu.

2. Click Device Manager. Type the administrator password or

3. Expand Bluetooth to display all Bluetooth devices. Right-click

The Bluetooth feature does not work.

4. Expand Network adapters to display all network devices.

• Turn on the Bluetooth radio.

1. Open the Start menu.

2. Click Settings ➙ Devices ➙ Bluetooth & other devices.

3. Turn on the Bluetooth switch to enable the Bluetooth feature.

• Update or reinstall the Bluetooth driver.

provide confirmation if prompted.

each Bluetooth device, and then click Enable device.

Right-click each Bluetooth device, and then click Enable
device.

Sound does not come from the Bluetooth
headset or headphones.

Select the Bluetooth headset or headphones as the default audio
output device in advanced sound settings.

Chapter 5. Troubleshooting, diagnostics, and recovery 43

Performance problems

Problem Solution

Note: Depending on the volume of the storage drives and amount of

data stored on the storage drives, the disk-defragmentation process
might take up to several hours.

1. Close any open programs and windows.

2. Open the Start menu.
Excessive fragmented files exist on the
storage drives.

The free storage drive space is insufficient.

3. Click Windows System ➙ File Explorer ➙ This PC.

4. Right-click your C drive and then click Properties.

5. Click the Tools tab.

6. Click Optimize. Select the drive as desired, and then click

7. Follow the on-screen instructions.

• Clean out your Inbox, Sent Items, and Deleted Items folders from
your e-mail application.

• Clean up your C drive.

1. Open the Start menu.

2. Click Windows System ➙ File Explorer ➙ This PC.

3. Right-click your C drive and then click Properties.

4. Check the amount of free space, and then click Disk Cleanup.

5. A list of unnecessary file categories is displayed. Select the

• Disable some Windows features or remove some unnecessary
programs.

1. Go to Control Panel and view by large icons or small icons.

2. Click Programs and Features.

3. Do one of the following:

Optimize.

category you want to delete, and then click OK.

– To disable some Windows features, click Turn Windows

features on or off. Follow the on-screen instructions.

– To remove some unnecessary programs, select the

program you want to remove, and then click Uninstall/
Change or Uninstall.

The free memory space is insufficient.

44 M75s Gen 2 Hardware Maintenance Manual

• Right-click a blank area on the taskbar and open Task Manager.
Then, end some tasks you are not performing.

• Install additional memory modules.

Storage drive problems

Problem Solution

• Ensure that the signal cables and power cables for all the storage

drives are connected correctly.

• Ensure that the computer is configured correctly to support the

storage drives.
Some or all storage drives are missing from
the BIOS menu.

– If the computer is installed with SATA storage drives, ensure

– If the computer is installed with SAS storage drives, ensure that

CD or DVD problems

Problem Solution

• Ensure that the optical drive supports the CD or DVD.

• Ensure that the disc is inserted correctly, with its label up.

• Ensure that the disc you are using is clean. To remove dust or
fingerprints, wipe the disc clean with a soft cloth from the center to
the outside. Wiping a disc in a circular motion might cause loss of
data.

A CD or DVD does not work.

• Ensure that the power cable and signal cable are securely
connected to the drive.

• Ensure that the disc you are using is not scratched or damaged.
Try inserting another disc that you know works.

• If you have multiple CD or DVD drives installed (or a combination of
CD and DVD drives), try inserting the disc into the other drive. In
some cases, only one of the drives is connected to the audio
subsystem.

that the SATA storage drive enablement module (one to five
storage drives) is installed.

the SAS storage drive enablement module (one to five storage
drives) or the LSI MegaRAID SAS adapter is installed.

A bootable recovery medium, such as the
Product Recovery CD, cannot be used to
start your computer.

A black screen is displayed instead of the
DVD video.

A DVD movie does not play.

No audio or only an intermittent audio comes
out while a DVD movie is playing.

Ensure that the CD or DVD drive is set as the top priority of the boot
priority order in UEFI BIOS.
Note: On some computer models, the startup sequence is
permanently set and cannot be changed.

• Restart the DVD player program.

• Try a lower screen resolution or color depth.

• Close any open files, and then restart the computer.

• Ensure that the disc surface is clean and not scratched.

• Check the disc or packaging for regional coding. You might need
to purchase a disc with coding for the region where you are using
the computer.

• Check the volume control settings on the computer and on your
speakers.

• Ensure that the disc surface is clean and not scratched.

• Check all cable connections to and from the speakers.

• Use the DVD menu for the video to select a different audio track.

Chapter 5. Troubleshooting, diagnostics, and recovery 45

Problem Solution

• Disable any background programs, such as AntiVirus or Desktop

The playback is slow or choppy.

A message indicating invalid disc or no disc
found is displayed.

Themes.

• Ensure that video resolution is less than 1152 x 864 pixels.

• Ensure that the disc is in the drive with the shiny side of the disc
facing down.

• Ensure that video resolution is less than 1152 x 864 pixels.

• Ensure that the DVD or CD is inserted into an appropriate optical
drive. For example, do not insert a DVD into a CD-only drive.

Serial connector problems

Problem Solution

• Connect the serial cable from the serial connector on the computer
to the serial device. If the serial device has its own power cord,
connect the power cord to a grounded electrical outlet.

• Turn on the serial device and keep the device online.

The serial connector cannot be accessed.

• Install any programs supplied with the serial device. Refer to the
documentation that comes with the serial device for more
information.

• If you added one serial-connector adapter, ensure that the adapter
is installed correctly.

USB device problems

Problem Solution

• Connect the USB cable from the USB connector to the USB
device. If the USB device has its own power cord, connect the
power cord to a grounded electrical outlet.

• Turn on the USB device and keep the device online.

A USB device cannot be accessed.

• Install any device drivers or programs supplied with the USB
device. Refer to the documentation that comes with the USB
device for more information.

• Disconnect and reconnect the USB connector to reset the USB
device.

• Ensure that the Smart USB Protection function is disabled in UEFI
BIOS.

46 M75s Gen 2 Hardware Maintenance Manual

Software problems

Problem Solution

1. Check whether the problem is caused by a program.
a. Ensure that the software is compatible with the computer.

Refer to the information supplied with the software for more

information.
b. Verify that other software works correctly on the computer.
c. Verify that the software you are using works on another

Some programs do not work as expected.

computer.

2. If the problem is caused by a program:

• Refer to the printed documentation that comes with the

program or the help system of the program.

• Update the program.

• Uninstall the program and then reinstall it. To download a

program that is preinstalled on your computer, go to

pcsupport.lenovo.com

and follow the on-screen instructions.

https://

Diagnostics

Use diagnostic solutions to test hardware components and report operating-system-controlled settings that
interfere with the correct operation of your computer.

Lenovo diagnostic tools

For information about Lenovo diagnostic tools, go to:

https://pcsupport.lenovo.com/lenovodiagnosticsolutions

UEFI diagnostic program

A UEFI diagnostic program is preinstalled on the computer. It enables you to test memory modules and
internal storage devices, view system information, and check and recover bad sectors on internal storage
devices.

To run the UEFI diagnostic program, do the following:

1. Turn on the computer. If the computer cannot be turned on, go to “Basic procedure for resolving
computer problems” on page 39. If an error code is displayed, go to “Symptom-to-FRU index” on page
32 for error code descriptions and troubleshooting hints.

2. Repeatedly press and release the F10 key when turning on the computer. The main screen of the UEFI
diagnostic program is displayed.

3. Follow the instructions on the screen to use the diagnostic program.

The options on the main screen are as follows:

Chapter 5. Troubleshooting, diagnostics, and recovery 47

Table 1. Options on the main screen of the UEFI diagnostic program

DIAGNOSTICS TOOLS

• CPU [U]

• DISPLAY [D]

• KEYBOARD [K]

• MEMORY [E]

• MOTHERBOARD [H]

• MOUSE [W]

• PCI EXPRESS [P]

• STORAGE [S]

• RUN ALL [R]

Note: The options on the main screen might vary, depending on the hardware configuration and the UEFI
diagnostic program version preinstalled on the computer.

• SYSTEM INFORMATION [F1]

• BAD BLOCK RECOVERY [F3]

• SMART INFORMATION [F5]

Recovery

This section introduces the recovery information of the Windows 10 operating system. Ensure that you read
and follow the on-screen recovery instructions. The data on your computer might be deleted during the
recovery process. To avoid data loss, make a backup copy of all the data that you want to keep.

Restore system files and settings to an earlier point

1. Go to Control Panel and view by large icons or small icons.

2. Click Recovery ➙ Open System Restore. Then, follow the on-screen instructions.

Restore your files from a backup

Note: If you use the File History tool to restore your files from a backup, ensure that you backed up your

data earlier with the tool.

1. Go to Control Panel and view by large icons or small icons.

2. Click File History ➙ Restore personal files. Then, follow the on-screen instructions.

Reset your computer

In the resetting process, you can choose to keep your files or remove them when you reinstall the operating
system.

Note: The items in the graphical user interface (GUI) might change without notice.

1. Open the Start menu, and then click Settings ➙ Update & Security ➙ Recovery.

2. In the Reset this PC section, click Get started.

3. Follow the on-screen instructions to reset your computer.

Use advanced options

1. Open the Start menu, and then click Settings ➙ Update & security ➙ Recovery.

2. In the Advanced startup section, click Restart now ➙ Troubleshoot ➙ Advanced options.

3. Select a preferred option, and then follow the on-screen instructions.

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M75s Gen 2 Hardware Maintenance Manual

Windows automatic recovery

Note: Ensure that your computer is connected to ac power during the recovery process.

The Windows recovery environment on your computer operates independently from the Windows 10
operating system. It enables you to recover or repair the operating system even if the Windows 10 operating
system fails to start.

After two consecutive failed boot attempts, the Windows recovery environment starts automatically. Then,
you can choose repair and recovery options by following the on-screen instructions.

Create and use a recovery USB device

It is recommended that you create a recovery USB drive as early as possible as a backup for the Windows
recovery programs. With the recovery USB drive, you can troubleshoot and fix the problems even if the
preinstalled Windows recovery programs are damaged. If you did not create a recovery USB drive as a
precautionary measure, you can contact Lenovo Customer Support Center and purchase one from Lenovo.
For a list of the Lenovo Support phone numbers for your country or region, go to:

https://pcsupport.lenovo.com/supportphonelist

Create a recovery USB drive
Attention: The creation process deletes anything stored on the USB drive. To avoid data loss, make a

backup copy of all the data that you want to keep.

1. Ensure that your computer is connected to ac power.

2. Prepare a USB drive with capacity of at least 16 GB. The actual USB capacity required depends on the
size of the recovery image.

3. Connect the prepared USB drive to the computer.

4. Type recovery in the search box. Then, click Create a recovery drive.

5. Click Yes in the User Account Control window to allow the Recovery Media Creator program to start.

6. In the Recovery Drive window, follow the on-screen instructions to create a recovery USB drive.

Use the recovery USB drive

If your computer cannot be started, go to
the problem by yourself. If the problem persists, use the recovery USB drive to recover your computer.

1. Ensure that your computer is connected to ac power.

2. Connect the recovery USB drive to the computer.

3. Turn on or restart the computer. When the logo screen is displayed, press F12. The Boot Menu window
opens.

4. Select the recovery USB drive as the boot device. Then, follow the on-screen instructions to complete
the process.

https://pcsupport.lenovo.com/supportphonelist first to try to solve

Update the device driver

Attention: Reinstalling device drivers will change the current configuration of the computer.

You should download the latest driver for a component when you notice poor performance from that
component or when you added a component. This action might eliminate the driver as the potential cause of
a problem. Download and install the latest driver by one of the following methods:

• From the Vantage app:

Chapter 5. Troubleshooting, diagnostics, and recovery 49

Open the Vantage app to check the available update packages. If the latest UEFI BIOS update package is
available, follow the on-screen instructions to download and install the package.

• From the Lenovo Support Web site:
Go to

https://pcsupport.lenovo.com and select the entry for your computer. Then, follow the on-screen

instructions to download and install necessary drivers and software.

• From Windows Update:

Note: The device drivers provided by Windows Update might not be tested by Lenovo. It is
recommended that you get device drivers from Lenovo.

1. Open the Start menu.

2. Click Settings ➙ Update & Security ➙ Windows Update.

3. Follow the on-screen instructions.

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M75s Gen 2 Hardware Maintenance Manual

Chapter 6. Hardware removal and installation

This chapter provides instructions on how to remove and install hardware for your computer.

Handling static-sensitive devices

Do not open the static-protective package containing the new part until the defective part has been removed
and you are ready to install the new part. Static electricity, although harmless to you, can seriously damage
computer components and options.

When you handle options and other computer components, take these precautions to avoid static-electricity
damage:

• Limit your movement. Movement can cause static electricity to build up around you.

• Always handle options and other computer components carefully. Handle PCI/PCIe cards, memory
modules, system boards, and microprocessors by the edges. Never touch any exposed circuitry.

• Prevent others from touching the options and other computer components.

• Touch the static-protective package containing the part to a metal expansion-slot cover or other
unpainted metal surface on the computer for at least two seconds. This reduces static electricity from the
package and your body before you install or replace a new part.

• When possible, remove the new part from the static-protective package, and install it directly in the
computer without setting the part down. When this is not possible, place the static-protective package on
a smooth, level surface and place the part on the package.

• Do not place the part on the computer cover or other metal surface.

Service tool kit

Ensure that the following common service tool kit is prepared before you service the computer.

No. Tool name Tool type

1 Phillips-head screwdriver

2

3 Pry tools

4

5 Isolated tweezers

6 Hexagonal socket

7

8 Polyamide tape Consumable tool

9 Mylar tape

10 Eraser Consumable tool

11 Electrical tape Consumable tool

12 Double-sided tape Consumable tool

13

Torx-head screwdriver (for new Intel Xeon CPUs) Common tool

Conductive tweezers Common tool

Silicone grease Consumable tool

Conductive tape Consumable tool

Common tool

Common tool

Common tool

Common tool

Consumable tool

© Copyright Lenovo 2020 51

Note: The silicone grease can be applied to the surfaces of the microprocessor and heat sink to eliminate air
gaps. The hexagonal socket is used to pick up the antenna connectors.

Major FRUs and CRUs

Your computer contains the following types of CRUs and FRUs:

• Self-service CRUs: Refer to parts that can be installed or replaced easily by customer themselves or by
trained service technicians at an additional cost.

• Optional-service CRUs: Refer to parts that can be installed or replaced by customers with a greater skill
level. Trained service technicians can also provide service to install or replace the parts under the type of
warranty designated for the customer’s machine.

• FRUs: Refer to parts that must be installed or replaced only by trained service technicians. If customers
choose to replace the FRUs by themselves, the product warranty might be affected.

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M75s Gen 2 Hardware Maintenance Manual

Number Description

Self-service CRU Optional-service CRU

1

2

3

4

5

6

7

Heat sink and fan assembly No No

Memory module Yes No

Microprocessor No No

System board

Coin-cell battery

No No

No Yes

Wi-Fi card* No No

Wi-Fi card shield* No No

Chapter 6. Hardware removal and installation 53

Number Description Self-service CRU Optional-service CRU

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

8

9

M.2 solid-state drive* Yes No

M.2 solid-state drive bracket* Yes No

Heat sink and thermal pad (type 2)* Yes No

Heat sink and thermal pad (type 1)* Yes No

Cover presence switch

Card reader*

Card reader bracket*

No No

No No

No No

Illuminated red dot cable and clip No No

Power button No No

Front I/O bracket No No

Thermal sensor No No

Internal speaker* No No

Optical drive bracket*

Optical drive*

Yes No

Yes No

Optical drive cable* No No

Front bezel Yes No

Vertical stand* Yes No

Power cord Yes No

Mouse* Yes No

Keyboard* Yes No

28

29

30

31

32

33

34

35

36

37

38

39

40

41

Primary storage drive bracket* Yes No

Primary storage drive* Yes No

Secondary storage drive bracket*

Secondary storage drive*

Storage converter*

Storage drive cable* No No

Chassis

Power supply assembly No Yes

Wi-Fi antennas* No No

E-lock* No Yes

PCI-Express card*

Rear I/O shielding No No

Thumb screws Yes No

Computer cover

* for selected models

Yes No

Yes No

Yes No

No No

Yes No

Yes No

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M75s Gen 2 Hardware Maintenance Manual

For detailed FRU and CRU information, such as the FRU part numbers and supported computer models, go
to:

http://www.lenovo.com/serviceparts-lookup

System board

1 4-pin power connector 2 Microprocessor socket

3 Microprocessor fan connector

5 Memory slot (DIMM2) 6 Memory slot (DIMM3)

7 Memory slot (DIMM4)

9 Power button connector 10 Internal speaker connector

11 10-pin power connector

13 Auxiliary fan connector 1

15 Buzzer 16 M.2 solid-state drive slot

17 M.2 Wi-Fi card slot 18 Thermal sensor connector

19 Illuminated red dot connector

21 Front USB connector 1 22 LPC debug connector

23 Parallel connector

25 Clear CMOS / Recovery jumper 26 Coin-cell battery

27 PCI-Express x1 card slot 28 PCI-Express x16 graphics card slot

4 Memory slot (DIMM1)

8 Auxiliary fan connector 2

12 SATA power connectors

14 SATA 3.0 connectors

20 Front USB connector 2

24 Serial (COM2) connector

Chapter 6. Hardware removal and installation 55

29 System fan connector

31 Cover presence switch connector

30 E-lock connector

Removing and installing hardware

This section provides instructions on how to remove and install hardware for your computer. You can expand
the capabilities of your computer and maintain your computer by removing or installing hardware.

Attention: Do not open your computer or attempt any repair before reading and understanding the Chapter
1 “Important safety information” on page 1.

Vertical stand

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, do the following:

1. Remove any media from the drives and turn off all connected devices and the computer.

2. Disconnect all power cords from electrical outlets and disconnect all cables from the computer.

Removal steps

Computer cover

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

56 M75s Gen 2 Hardware Maintenance Manual

Before you open the computer cover, turn off the computer and wait several minutes until the computer is
cool.

For access, do the following:

1. Remove any media from the drives and turn off all connected devices and the computer.

2. Disconnect all power cords from electrical outlets and disconnect all cables from the computer.

3. Unlock any locking device that secures the computer cover.

4. Remove the vertical stand. See “Vertical stand” on page 56.

5. Lay down the computer with the computer cover facing up.

Removal steps

Note: If a locking device is available, use it to lock the computer.

Front bezel

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, remove the computer cover. See “Computer cover” on page 56.

Chapter 6. Hardware removal and installation 57

Replacement procedure

Optical drive

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, do the following:

1. Remove the computer cover. See “Computer cover” on page 56.

2. Disconnect the signal and power cable from the optical drive.

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Replacement procedure

Chapter 6. Hardware removal and installation 59

Drive bay assembly

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, remove the following parts in order:

• “Computer cover” on page 56

• “Front bezel” on page 57

Replacement procedure

60 M75s Gen 2 Hardware Maintenance Manual

Hard disk drive

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

Attention: The internal storage drive is sensitive. Inappropriate handling might cause damage and
permanent loss of data. When handling the internal storage drive, observe the following guidelines:

• Replace the internal storage drive only for upgrade or repair. The internal storage drive is not designed for
frequent changes or replacement.

• Before replacing the internal storage drive, make a backup copy of all the data that you want to keep.

• Do not touch the contact edge of the internal storage drive. Otherwise, the internal storage drive might get
damaged.

• Do not apply pressure to the internal storage drive.

• Do not make the internal storage drive subject to physical shocks or vibration. Put the internal storage
drive on a soft material, such as cloth, to absorb physical shocks.

Removal steps for 3.5-inch primary hard disk drive

For access, do the following:

1. Remove the following parts in order, if any:

• “Computer cover” on page 56

• “Front bezel” on page 57

• “Drive bay assembly” on page 60

2. On the bottom of the drive bay assembly, disconnect the signal cable and the power cable from the 3.5­inch primary hard disk drive.

Chapter 6. Hardware removal and installation 61

Removal steps for 2.5-inch primary hard disk drive

Remove the storage converter with the 2.5-inch primary storage drive. See “3.5-inch primary hard disk drive”
on page 61.

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Removal steps for 2.5-inch secondary hard disk drive

For access, do the following:

1. Remove the following parts in order, if any:

• “Computer cover” on page 56

• “Front bezel” on page 57

• “Optical drive” on page 58

• “Drive bay assembly” on page 60

2. On the bottom of the drive bay assembly, disconnect the signal cable and the power cable from the 2.5­inch secondary hard disk drive.

Chapter 6. Hardware removal and installation 63

M.2 solid-state drive and heat sink

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

The heat sink might be very hot. Before you open the computer cover, turn off the computer and wait several
minutes until the computer is cool.

Attention: The internal storage drive is sensitive. Inappropriate handling might cause damage and
permanent loss of data. When handling the internal storage drive, observe the following guidelines:

• Replace the internal storage drive only for upgrade or repair. The internal storage drive is not designed for
frequent changes or replacement.

• Before replacing the internal storage drive, make a backup copy of all the data that you want to keep.

• Do not touch the contact edge of the internal storage drive. Otherwise, the internal storage drive might get
damaged.

• Do not apply pressure to the internal storage drive.

• Do not make the internal storage drive subject to physical shocks or vibration. Put the internal storage
drive on a soft material, such as cloth, to absorb physical shocks.

For access, remove the following parts in order, if any:

• “Computer cover” on page 56

• “Front bezel” on page 57

• “Drive bay assembly” on page 60

Removal steps

Replace the M.2 solid-state drive and the heat sink depending on the computer model:

• For computers without the heat sink for the M.2 solid-state drive, do the following:

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• For computers with the heat sink for the M.2 solid-state drive, do one of the following depending on the
computer model:

– Type 1

Note: Remove the film that covers the thermal pad (if any) when installing the M.2 solid-state drive and
the heat sink.

– Type 2

Chapter 6. Hardware removal and installation 65

Note: Remove the film that covers the thermal pad (if any) when installing the M.2 solid-state drive and
the heat sink.

– Type 3

Note: Remove the film that covers the thermal pad (if any) when installing the M.2 solid-state drive and
the heat sink.

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M.2 solid-state drive bracket

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, remove the following parts in order, if any:

• “Computer cover” on page 56

• “Front bezel” on page 57

• “Drive bay assembly” on page 60

• “M.2 solid-state drive and heat sink” on page 64

Replacement procedure

Wi-Fi card

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, remove the following parts in order, if any:

• “Computer cover” on page 56

• “Front bezel” on page 57

• “Drive bay assembly” on page 60

Chapter 6. Hardware removal and installation 67

Removal steps

Front Wi-Fi antenna

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, do the following:

1. Remove the following parts in order, if any:

• “Computer cover” on page 56

• “Front bezel” on page 57

• “Drive bay assembly” on page 60

2. Disconnect the Wi-Fi antenna cables from the Wi-Fi card. See “Wi-Fi card” on page 67.

Replacement procedure

Rear Wi-Fi antenna

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

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M75s Gen 2 Hardware Maintenance Manual

Replacement procedure

Memory module

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

Ensure that you follow the installation order for memory modules shown in the following illustration.

For access, remove the following parts in order, if any:

Chapter 6. Hardware removal and installation 69

• “Computer cover” on page 56

• “Front bezel” on page 57

• “Drive bay assembly” on page 60

Replacement procedure

Note: During the installation, ensure that you align the memory module to the slot and press down on both

ends until the latches are fully engaged with a click.

PCI-Express card

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, remove the computer cover. See “Computer cover” on page 56.

Removal steps

70 M75s Gen 2 Hardware Maintenance Manual

Note: Remove any PCI-Express connector cables that impede the installation of PCI-Express cards.

Coin-cell battery

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

Your computer has a special type of memory that maintains the date, time, and settings for built-in features,
such as parallel connector assignments (configurations). A coin-cell battery keeps this information active
when you turn off the computer.

The coin-cell battery normally requires no charging or maintenance throughout its life; however, no coin-cell
battery lasts forever. If the coin-cell battery fails, the date and time information is lost. An error message is
displayed when you turn on the computer.

For access, remove the computer cover. See “Computer cover” on page 56.

Removal steps

Notes:

• Reset the system date and time in the UEFI BIOS menu.

• To dispose of the coin-cell battery, refer to the “Lithium coin-cell battery notice” in the Safety and
Warranty Guide.

Power supply assembly

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

Although there are no moving parts in the computer after the power cord has been disconnected, the
following warnings are required for your safety.

Chapter 6. Hardware removal and installation 71

Keep fingers and other parts of your body away from hazardous, moving parts. If you suffer an injury, seek
medical care immediately. Never remove the cover on a power supply or any part that has the following label
attached.

Hazardous voltage, current, and energy levels are present inside any component that has this label attached.
There are no serviceable parts inside these components. If you suspect a problem with one of these parts,
contact a service technician.

For access, do the following:

1. Remove the following parts in order, if any:

• “Computer cover” on page 56

• “Front bezel” on page 57

• “Drive bay assembly” on page 60

2. Disconnect the power supply assembly cables from the system board.

Removal steps

E-lock

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, do the following:

1. Remove the following parts in order, if any:

• “Computer cover” on page 56

• “PCI-Express card” on page 70

2. Disconnect the E-lock cable from the system board.

Note: To remove the screws, you need a special tool (T15 star wrench).

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Removal steps

Internal speaker

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, do the following:

1. Remove the following parts in order, if any:

• “Computer cover” on page 56

• “Front bezel” on page 57

• “Drive bay assembly” on page 60

2. Disconnect the internal speaker cable from the system board.

Removal steps

Illuminated red dot cable

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, do the following:

1. Remove the following parts in order, if any:

• “Computer cover” on page 56

• “Front bezel” on page 57

Chapter 6. Hardware removal and installation 73

• “Drive bay assembly” on page 60

2. Disconnect the illuminated red dot cable from the system board.

Removal steps

Thermal sensor

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, do the following:

1. Remove the following parts in order, if any:

• “Computer cover” on page 56

• “Front bezel” on page 57

• “Drive bay assembly” on page 60

2. Disconnect the thermal sensor cable from the system board.

Removal steps

Front I/O bracket and power button

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

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M75s Gen 2 Hardware Maintenance Manual

For access, do the following:

1. Remove the following parts in order, if any:

• “Computer cover” on page 56

• “Front bezel” on page 57

• “Drive bay assembly” on page 60

2. Disconnect the power button cable and the card reader cable from the system board.

Replacement procedure

Chapter 6. Hardware removal and installation 75

Card reader and card reader bracket

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, do the following:

1. Remove the following parts in order, if any:

• “Computer cover” on page 56

• “Front bezel” on page 57

• “Drive bay assembly” on page 60

• “Front I/O bracket and power button” on page 74

2. Disconnect the card reader cable from the system board.

Removal steps

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Heat sink and fan assembly

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, do the following:

1. Remove the following parts in order, if any:

• “Computer cover” on page 56

• “Optical drive” on page 58

2. Disconnect the microprocessor fan cable from the system board.

Replacement procedure

Chapter 6. Hardware removal and installation 77

Microprocessor

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

CAUTION:

The heat sink and microprocessor might be very hot. Before you open the computer cover, turn off the
computer and wait several minutes until the computer is cool.

For access, remove the following parts in order, if any:

• “Computer cover” on page 56

• “Optical drive” on page 58

• “Heat sink and fan assembly” on page 77

Notes:

• Touch only the edges of the microprocessor. Do not touch the gold contacts on the bottom.

• Do not drop anything onto the microprocessor socket while it is exposed. The socket pins must be kept
as clean as possible.

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Removal steps

Cover presence switch

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, do the following:

1. Remove the computer cover. See “Computer cover” on page 56.

2. Disconnect the cover presence switch cable from the system board.

Removal steps

System board

Prerequisite

Before you start, read Chapter 1 “Important safety information” on page 1 and print the following
instructions.

For access, do the following:

1. Remove the following parts in order, if any:

• “Computer cover” on page 56

• “Front bezel” on page 57

Chapter 6. Hardware removal and installation 79

• “Drive bay assembly” on page 60

• “M.2 solid-state drive and heat sink” on page 64

• “M.2 solid-state drive bracket” on page 67

• “Wi-Fi card” on page 67

• “Memory module” on page 69

• “PCI-Express card” on page 70

• “Front I/O bracket and power button” on page 74

• “Card reader and card reader bracket” on page 76

• “Heat sink and fan assembly” on page 77

• “Microprocessor” on page 78

2. Record the cable routing and cable connections, and then disconnect all cables from the system board.
See “System board” on page 55.

Notes:

• Carefully handle the system board by its edges.

• Do not touch the pins on the microprocessor socket or the gold contacts on the microprocessor.

Removal steps

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Chapter 7. Notices and trademarks

Notices

Lenovo may not offer the products, services, or features discussed in this document in all countries. Consult
your local Lenovo representative for information on the products and services currently available in your
area. Any reference to a Lenovo product, program, or service is not intended to state or imply that only that
Lenovo product, program, or service may be used. Any functionally equivalent product, program, or service
that does not infringe any Lenovo intellectual property right may be used instead. However, it is the user's
responsibility to evaluate and verify the operation of any other product, program, or service.

Lenovo may have patents or pending patent programs covering subject matter described in this document.
The furnishing of this document does not give you any license to these patents. You can send license
inquiries, in writing, to:

Lenovo (United States), Inc.
8001 Development Drive
Morrisville, NC 27560
U.S.A.
Attention: Lenovo Director of Licensing

LENOVO PROVIDES THIS PUBLICATION "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS
OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF NON-INFRINGEMENT,
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Some jurisdictions do not allow
disclaimer of express or implied warranties in certain transactions, therefore, this statement may not apply to
you.

Changes are made periodically to the information herein; these changes will be incorporated in new editions
of the publication. To provide better service, Lenovo reserves the right to improve and/or modify the
products and software programs described in the manuals included with your computer, and the content of
the manual, at any time without additional notice.

The software interface and function and hardware configuration described in the manuals included with your
computer might not match exactly the actual configuration of the computer that you purchase. For the
configuration of the product, refer to the related contract (if any) or product packing list, or consult the
distributor for the product sales. Lenovo may use or distribute any of the information you supply in any way it
believes appropriate without incurring any obligation to you.

The products described in this document are not intended for use in implantation or other life support
applications where malfunction may result in injury or death to persons. The information contained in this
document does not affect or change Lenovo product specifications or warranties. Nothing in this document
shall operate as an express or implied license or indemnity under the intellectual property rights of Lenovo or
third parties. All information contained in this document was obtained in specific environments and is
presented as an illustration. The result obtained in other operating environments may vary.

Lenovo may use or distribute any of the information you supply in any way it believes appropriate without
incurring any obligation to you.

Any references in this publication to non-Lenovo Web sites are provided for convenience only and do not in
any manner serve as an endorsement of those Web sites. The materials at those Web sites are not part of the
materials for this Lenovo product, and use of those Web sites is at your own risk.

Any performance data contained herein was determined in a controlled environment. Therefore, the result
obtained in other operating environments may vary significantly. Some measurements may have been made

© Copyright Lenovo 2020 81

on development-level systems and there is no guarantee that these measurements will be the same on
generally available systems. Furthermore, some measurements may have been estimated through
extrapolation. Actual results may vary. Users of this document should verify the applicable data for their
specific environment.

This document is copyrighted by Lenovo and is not covered by any open source license, including any Linux
agreement(s) which may accompany software included with this product. Lenovo may update this document
at any time without notice.

For the latest information or any questions or comments, contact or visit the Lenovo Web site:

https://pcsupport.lenovo.com

Trademarks

LENOVO, LENOVO logo, THINKCENTRE, and THINKCENTRE logo are trademarks of Lenovo. Microsoft and
Windows are trademarks of the Microsoft group of companies. DisplayPort is a trademark of the Video
Electronics Standards Association. The terms HDMI and HDMI High-Definition Multimedia Interface are
trademarks or registered trademarks of HDMI Licensing LLC in the United States and other countries. Wi-Fi
is a registered trademark of Wi-Fi Alliance. USB-C is a trademark of USB Implementers Forum. All other
trademarks are the property of their respective owners. © 2020 Lenovo.

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