Advanced Micro Devices (AMD). Hereby Intel models and AMD models are used to distinguish computer models with different microprocessors. ThinkPad L14 Gen 4 and ThinkPad L15 Gen 4 also might be shipped with different GPUs (graphics processing units), namely Discrete GPU (DIS) and Unified Memory Architeture (UMA). Hereby DIS models and UMA models are used to distinguish computer models with different GPUs.
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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. ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
4. Check for cracked or bulging batteries. 5. Remove the cover. 6. Check for any obvious non-ThinkPad / non-Lenovo alterations. Use good judgment as to the safety of any non-ThinkPad / non-Lenovo alterations. 7. Check inside the unit for any obvious unsafe conditions, such as metal filings, contamination, water or other liquids, or signs of fire or smoke damage.
The safety notices in this section are provided in the following languages: • English • Arabic • Brazilian Portuguese • French • German • Hebrew • Japanese • Korean • Spanish • Traditional Chinese DANGER DANGER ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
– “FRU identification” on page 20 Important: • Advise customers to contact the Lenovo Customer Support Center if they need any assistance in obtaining or installing any software fixes, drivers, and UEFI BIOS downloads. Telephone numbers for Lenovo Support are available at: https://pcsupport.lenovo.com/supportphonelist...
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.
Note: If you are unable to isolate and repair the problem yourself after running the program, save and print the log files created by the program. You need the log files when you speak to a Lenovo technical support representative.
Run quick test programs to troubleshoot and resolve computer problems, especially when the computer does not have the Vantage app installed. To download and install a quick test program, go to https://www.lenovo.com/diags , and follow the instructions on the Web site.
If the computer you are servicing is not installed with the UEFI diagnostic program, you can download a bootable diagnostic program from the Lenovo Support Web site. The bootable diagnostic program enables you to view system information and test some hardware devices in your computer, such as memory, storage devices, the LCD, and system board buses.
Checking the built-in battery and operational charging This system supports only batteries specially designed for this specific system and manufactured by Lenovo or an authorized manufacturer. The system does not support unauthorized batteries or batteries designed for other systems.
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• If the voltage is correct, replace the system board. • If the voltage is not correct, replace the coin-cell battery. • If the coin-cell battery discharges quickly after replacement, replace the system board. ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
When the latest maintenance diskette and the system program service diskette become available, they will be posted on: https://support.lenovo.com Reset or restore Windows To reset or restore Windows, refer to the information below: • Use Lenovo recovery options. 1. Go to https://support.lenovo.com/HowToCreateLenovoRecovery 2. Follow the on-screen instructions. • Use Window recovery options.
The system management password can also protect the system information stored in UEFI BIOS like a supervisor password, but it has lower authority by default. The system management password can be set through the UEFI BIOS menu or through Windows Management Instrumentation (WMI) with the Lenovo client-management interface.
Lenovo cannot reset your passwords or recover data from the storage drive. You can contact a Lenovo authorized service provider to have the storage drive replaced. A fee will be charged for parts and service. If the storage drive is a CRU (Customer Replaceable Unit), you can also contact Lenovo to purchase a new storage drive to replace the old one by yourself.
Also, in either of the following events, the computer automatically returns from sleep mode and resumes operation: • The ring indicator (RI) is signaled by a serial device or a PC Card device. • The time set on the resume timer elapses. ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
Note: The computer does not accept any input immediately after it enters sleep mode. Wait a few seconds before taking any action to reenter operation mode. Hibernation mode In hibernation mode, the following occurs: • The system status, RAM, VRAM, and setup data are stored on the solid-state drive. •...
2. Replace the M.2 solid-state drive. HDD (HDD0) 3. Replace the system board. 2200 Have the computer serviced. Machine Type and Serial Number are invalid. 2201 Replace the system board. Machine UUID is invalid ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
Beep errors Lenovo SmartBeep technology enables you to decode beep errors with your smartphone when a black screen occurs with beeps from your computer. To decode the beep error with Lenovo SmartBeep technology, do the following: 1.
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The following section describes some beep errors and the corresponding solutions. Note: Do not attempt to service a product yourself unless instructed to do so by the Customer Support Center or product documentation. Only use a Lenovo-authorized service provider to repair your product. Error codes...
Error codes Solutions 0287: Discrete graphics error 1. Reinstall or replace the discrete graphics card (service provider only). 2. If step 1 does not work, replace the system board (service provider only). 1. Reconnect the display cable on both the system board side and the computer display side (service provider only) and check the LCD panel.
If the LCD you are servicing has two or less visible defective pixels, it should not be considered faulty. However, if the LCD has three or more visible defective pixels, it will be deemed as defective by Lenovo and it should be replaced.
Table 4. LCD-related symptoms FRU or action, in sequence Symptom or error No beep, power-on indicator on, and a blank LCD during 1. Run LCD Self Test. POST. 2. Replace the system board. • LCD backlight not working. 1. Reseat the LCD connectors. •...
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Break operation Pause operation Scroll contents Send system request Enter sleep mode To wake up the computer, press Fn or the power button. Go to beginning Go to end ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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Infrared camera / Camera Microphone Touch screen Power button / Power button with ® TrackPoint pointing stick fingerprint reader NFC (near field communication) mark Trackpad Speaker TrackPoint buttons * for selected models ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
Lenovo will ship the CRU to you. CRU information and replacement instructions are shipped with your product and are available from Lenovo at any time upon request. You can find a list of CRUs for your product in this Hardware Maintenance Manual. An electronic version of this manual can be found at .
Major FRUs and CRUs ThinkPad L14 Gen 4 ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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Table 5. Major FRUs and CRUs FRU description Self-service Optional-service LCD unit Power button with bracket and fingerprint reader* Power button with bracket Fingerprint reader cable* Speaker NFC cable* NFC module* Keyboard bezel assembly USB and microSD board cable* USB and microSD board USB and microSD bracket Heat sink (for UMA models) System board (for DIS models)
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Miscellaneous parts kits (see “Miscellaneous parts” on page 55) Label kit * for selected models Note: Depending on the computer model, your computer might look different from the illustration above. ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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Coin-cell battery with cable Thermal fan System board (for UMA models) I/O bracket Heat sink (for DIS models) Smart card reader cable* Smart card reader* Dummy smart card reader* Trackpad cable ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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Table 6. Major FRUs and CRUs (continued) FRU description Self-service Optional-service Trackpad Keyboard Power cord ac power adapter Miscellaneous parts kits (see “Miscellaneous parts” on page 55) Label kit * for selected models Note: Depending on the computer model, your computer might look different from the illustration above. Chapter 6 Locations...
Hinges (for L15 Gen 4) Hinges (for L14 Gen 4) LCD panel * for selected models Note: Depending on the computer model, your computer might look different from the illustration above. ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
Miscellaneous parts Table 8. Miscellaneous part FRU descriptions Self-service Optional-service Screw kit for ThinkPad L14 Gen 4: • M2 x L2, silver – 13 (for UMA models) – 12 (for DIS models) • M2 x L3, black (8) • M2 x L4, black (4) •...
Connector and cable guide This topic provides information to help Lenovo authorized service technicians identify connectors and cables for replacement purpose. To view each FRU and the exploded illustration of the computer, see “Major FRUs and CRUs” on page 48 and “LCD FRUs and CRUs” on page 54.
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Table 9. System board connector and cable guide (for DIS models) (continued) Internal cable required Connector/feature Cable connection LCD connector (internal) LCD/camera/microphone cable Connect one end to the LCD panel, one end to the camera-and- microphone module, and another end to this connector. Speaker connector (internal) The speaker comes with cable.
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Connect the cable to this connector. Keyboard connector (internal) Keyboard assembly cable The keyboard assembly comes with the cable. Connect the cable to this connector. ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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System board connectors and cables (for UMA models) Table 10. System board connector and cable guide (for UMA models) Internal cable required Connector/feature Cable connection Fingerprint reader connector Fingerprint reader cable Connect one end to the fingerprint (internal) reader module and the other end to this connector.
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(internal) connector. USB and microSD board USB and microSD board cable Connect one end to the USB and connector (internal) microSD board, and the other end to this connector. ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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Table 10. System board connector and cable guide (for UMA models) (continued) Internal cable required Connector/feature Cable connection NFC connector (internal) NFC cable Connect one end to the NFC module and the other end to this connector. Thermal fan connector (internal) The thermal fan comes with the cable.
Connect one end to the system board and the other end to this connector. Looking up FRU information For detailed FRU information, including part numbers, descriptions, and substitution part numbers, go to: https://support.lenovo.com/partslookup ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
Maintenance Key. Note: Only an authorized Lenovo service technician can access the above Web site. 3. Restart the computer. 4. When the logo is displayed, press Esc. The ThinkPad Config Information Update Utility interface is displayed.
To check what ECAs have been previously applied to the machine, use the ECA Information Read/Write function on the LENOVO ThinkPad Hardware Maintenance Diskette or Maintenance Key. 1. Insert the latest version of LENOVO ThinkPad Hardware Maintenance Diskette or Maintenance Key, and then restart the computer.
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Note: Only the ECA number is stored in the EEPROM. The machine type of the ECA is assumed to be the same as the machine type of the machine that had the ECA applied to it. 1. Insert the latest version of LENOVO ThinkPad Hardware Maintenance Diskette or Maintenance Key, and then restart the computer.
Some models you are servicing might have a microSD card installed. If the computer you are servicing has a microSD card installed, remove the microSD card before you start the servicing. After you finish the servicing, ensure that you install the card back into the slot firmly. ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
1010 Keyboard Notes: • You might be instructed to slide the keyboard frame forward or backward in some of the following steps. In this case, ensure that you do not press or hold the keys while sliding the keyboard frame. Otherwise, the keyboard frame cannot be moved.
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Removal steps of the keyboard (for L15 Gen 4) ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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When installing: Configure the keyboard language in UEFI BIOS: 1. Enter the UEFI BIOS menu. 2. Click Config ➙ Keyboard/Mouse ➙ Keyboard Layout, and then select the keyboard language. Chapter 8 Removing or replacing a FRU...
1020 Base cover assembly Removal steps of the base cover assembly (for L14 Gen 4) ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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Removal steps of the base cover assembly (for L15 Gen 4) Applying labels to the base cover assembly Notes: • Depending on the country or region of delivery, the labels might be slightly different from the ones in the following illustration. •...
Note: Thermal pads are provided on both the upper and the lower surfaces of the M.2 solid-state drive. If you replace the M.2 solid-state drive, ensure that the thermal pads are attached in place. ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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Type 1 Torque Step Screw (quantity) Color M2 × 2 mm, flat-head, nylon-coated (2) Silver 0.181 Nm (1.85 kgf-cm) Type 2 Torque Step Screw (quantity) Color M2 × 2 mm, flat-head, nylon-coated (2) Silver 0.181 Nm (1.85 kgf-cm) Chapter 8 Removing or replacing a FRU...
Removal steps of the wireless WAN card (for selected UMA models) Step Screw (quantity) Color Torque M2 × 2 mm, flat-head, nylon-coated (1) Silver 0.181 Nm (1.85 kgf-cm) Removal steps of the wireless WAN card (for selected DIS models) ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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Step Screw (quantity) Color Torque M2 × 2 mm, flat-head, nylon-coated (1) Silver 0.181 Nm (1.85 kgf-cm) When installing: Ensure that you connect the orange cable to the main connector, and the blue cable to the auxiliary connector. Chapter 8 Removing or replacing a FRU...
M2 × 2 mm, flat-head, nylon-coated (1) Silver 0.181 Nm (1.85 kgf-cm) When installing: Plug the gray cable into the main connector, and the black cable into the auxiliary connector on the card. ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
1060 Speaker For access, remove this FRU: • “1020 Base cover assembly” on page 72 Removal steps of the speaker When installing: • Ensure that the connector is attached firmly. • Ensure that the cable is routed properly. Chapter 8 Removing or replacing a FRU...
ESC, F1, and F4 blinking sequentially to indicate the progress. Do not press the power button to interrupt the process. Wait a few minutes until the logo screen is displayed. ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
1080 USB and microSD bracket For access, remove this FRU: • “1020 Base cover assembly” on page 72 Removal steps of the USB and microSD bracket (for L14 Gen 4) Step Screw (quantity) Color Torque M2 × 4 mm, flat-head, nylon-coated (2) Black 0.181 Nm (1.85 kgf-cm)
For access of L14 Gen 4 models, additionally remove this FRU: • “1120 Built-in battery” on page 86 Removal steps of the USB and microSD board and cable (for L14 Gen 4) ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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Removal steps of the USB and microSD board and cable (for L15 Gen 4) Step Screw (quantity) Color Torque Black 0.181 Nm M2 × 4 mm, flat-head, nylon-coated (1) (1.85 kgf-cm) Chapter 8 Removing or replacing a FRU...
Important notice for replacing a battery Attention: Lenovo has no responsibility for the performance or safety of unauthorized batteries, and provides no warranties for failures or damage arising out of their use. The Vantage app provides an automatic battery diagnostic test that determines if the built-in battery is defective.
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For access, remove this FRU: • “1020 Base cover assembly” on page 72 Removal steps of the built-in battery Screw specifications of L14 Gen 4 Step Screw (quantity) Color Torque M2 × 5 mm, flat-head, nylon-coated (4) Black 0.181 Nm (1.85 kgf-cm) Screw specifications of L15 Gen 4 Step...
Use only the authorized battery specified for the computer. Any other battery could ignite or explode. For access, remove these FRUs in order: • “1020 Base cover assembly” on page 72 • “1120 Built-in battery” on page 86 ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
Removal steps of the coin-cell battery (for L14 Gen 4) Removal steps of the coin-cell battery (for L15 Gen 4) When installing: • Ensure that the connector is attached firmly. • Reset the system date and time in the BIOS menu. 1140 Smart card reader and cable (for selected models) For access, remove these FRUs in order: •...
1150 NFC module and NFC cable (for selected models) For access, remove these FRUs in order: • “1020 Base cover assembly” on page 72 • “1120 Built-in battery” on page 86 ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
Removal steps of the NFC module and NFC cable 1160 Trackpad and trackpad cable For access, remove these FRUs in order: • “1020 Base cover assembly” on page 72 • “1120 Built-in battery” on page 86 For access of NFC models, disconnect the NFC cable connector from the trackpad, see “1150 NFC module and NFC cable (for selected models)”...
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1. A trackpad jig might come with the trackpad which is used for fixing the location of the trackpad. Attach the trackpad jig to the trackpad and bend the four angles as shown by arrows below. ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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2. Install the trackpad with jig as shown. 3. Install the screws to fix the trackpad. Chapter 8 Removing or replacing a FRU...
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4. Remove the Jig. Notes: • A mylar might cover the trackpad, and ensure that you attach the mylar to the trackpad after replacement. • Ensure that the connector is attached firmly. 1170 Fingerprint reader cable (for selected models) For access, remove these FRUs in order: •...
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Removal steps of the fingerprint reader cable (for L15 Gen 4) When installing: Ensure that the connectors are attached firmly. ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
1180 Power board and power button with or without fingerprint reader For access, remove these FRUs in order: • “1020 Base cover assembly” on page 72 • “1100 Heat sink” on page 84 • “1170 Fingerprint reader cable (for selected models)” on page 95 Removal steps of the power board and power button with or without fingerprint reader (for L14 Gen 4) Step Screw (quantity)
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Removal steps of the power board and power button with or without fingerprint reader (for L15 Gen 4) ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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Step Screw (quantity) Color Torque M2.5 × 5 mm, flat-head, nylon-coated (1) Black 0.294 Nm (3.0 kgf-cm) M2 × 3.5 mm, flat-head, nylon-coated (1) Silver 0.181 Nm (1.85 kgf-cm) Chapter 8 Removing or replacing a FRU...
Step Screw (quantity) Color Torque M2.5 × 5 mm, flat-head, nylon-coated (3) Black 0.294 Nm (3.0 kgf-cm) M2 × 3 mm, flat-head, nylon-coated (2) Black 0.181 Nm (1.85 kgf-cm) ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
When installing: Ensure that the I/O bracket is attached firmly. 1200 System board Important notices for handling the system board: When handling the system board, read the following: • 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.
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Screw (quantity) Color Torque M2 × 3 mm, flat head, nylon-coated (2) Black 0.181 Nm (1.85 kgf-cm) M2 × 2 mm, flat head, nylon-coated (2) Silver 0.181 Nm (1.85 kgf-cm) ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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Removal steps of the system board (for L15 Gen 4) Step Screw (quantity) Color Torque M2 × 3 mm, flat head, nylon-coated (2) Black 0.181 Nm (1.85 kgf-cm) 0.181 Nm M2 × 2 mm, flat head, nylon-coated (2) Silver (1.85 kgf-cm) When installing: Configure the keyboard language in UEFI BIOS: 1.
Note: Depending on your computer model, the wireless WAN antennas might not be shipped. Step Screw (quantity) Color Torque M 2.5 × 4 mm, flat-head, nylon-coated (6) Black 0.294 Nm (3.0 kgf-cm) ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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Removal steps of the LCD unit (for L15 Gen 4) For access of L15 Gen 4 models, remove these FRUs in order: • “1020 Base cover assembly” on page 72 • “1080 USB and microSD bracket” on page 81 Note: Depending on your computer model, the wireless WAN antennas might not be shipped. Chapter 8 Removing or replacing a FRU...
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Step Screw (quantity) Color Torque Black 0.294 Nm M 2.5 × 5 mm, flat-head, nylon-coated (4) (3.0 kgf-cm) ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
When installing: Ensure that the connectors are attached firmly. Attention: When you route the cables, ensure that they are not subject to any tension. Tension could cause the cables to be damaged by the cable guides, or a wire to be broken. 1220 Keyboard bezel assembly For access, remove these FRUs: •...
1. Pull out each tape slowly in the direction as shown until the adhesive tapes are all released from LCD unit. Then, turn over the LCD panel. Note: Do not pull the tapes too fast, otherwise, the tapes might snap. ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
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2. Detach the LCD cable from the LCD panel as shown. Chapter 8 Removing or replacing a FRU...
• “1210 LCD unit” on page 104 • “2010 LCD bezel with webcam privacy shutter” on page 108 • “2020 LCD panel and elastic adhesive tapes” on page 108 Removal steps of the LCD/camera/microphone cable ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
2040 Hinges For access, remove these FRUs in order: • “1020 Base cover assembly” on page 72 • “1210 LCD unit” on page 104 • “2010 LCD bezel with webcam privacy shutter” on page 108 • “2020 LCD panel and elastic adhesive tapes” on page 108 Removal steps of the hinges Step Screw (quantity)
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Removal steps of the camera-and-microphone module ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
2060 Wireless antenna assembly For access, remove these FRUs in order: • “1020 Base cover assembly” on page 72 • “1210 LCD unit” on page 104 • “2010 LCD bezel with webcam privacy shutter” on page 108 • “2020 LCD panel and elastic adhesive tapes” on page 108 Removal steps of the wireless LAN antennas Chapter 8 Removing or replacing a FRU...
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Removal steps of the wireless WAN antennas (for selected models) ThinkPad L14 Gen 4 and L15 Gen 4 Hardware Maintenance Manual...
Attention: When you route the cables, ensure that they are not subject to any tension. Tension could cause the cables to be damaged by the cable guides, or a wire to be broken. Antenna locations Wireless-LAN auxiliary antenna (black) Wireless-WAN auxiliary antenna (blue)* Wireless-WAN main antenna (orange)* Wireless-LAN main antenna (gray) * for selected models...
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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.
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Trademarks LENOVO, LENOVO logo, THINKPAD, THINKPAD logo, and TRACKPOINT are trademarks of Lenovo. Intel and Thunderbolt are trademarks of Intel Corporation or its subsidiaries in the U.S. and/or other countries. Microsoft, Microsoft Teams, and Windows are trademarks of the Microsoft group of companies. 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.