1170 System Board - Lenovo ThinkPad Helix 20CG Hardware Maintenance Manual

Step Screw (quantity)
6
M2 × 4.5 mm, flat-head, nylon-coated (4)
Note: Do not close the connector flip before connecting the cable. When connecting the cable, ensure
that the connector is attached firmly.

1170 System board

Before you replace the system board, do the following:
1. Disable the built-in battery. See "Disabling the built-in battery" on page 46.
2. Remove the SIM card, SD card, and smart card. See "Removing the SIM card, SD card, and smart
card" on page 46.
3. Remove the following FRUs:
• "1010 Back cover assembly, smart-card reader, and smart-card-reader cable" on page 48
• "1030 Built-in battery" on page 53
• "1040 Wireless WAN card" on page 54
• "1050 M.2 solid-state drive and solid-state-drive mylar" on page 56
• "1060 Fingerprint-reader module" on page 57
• "1100 NFC card and NFC-card cable" on page 61
• "1130 Thermal module" on page 65
• "1140 USB-connector bracket" on page 67
Removal steps of the system board
CAUTION:
When handling the system board, read the following:
• The system board has an accelerometer, which can be broken when several thousands of G-forces
are applied.
• Be careful not to drop the system board on a bench top that has a hard surface, such as metal,
wood, or composite.
• Avoid rough handling of any kind.
• At every point in the process, be sure not to drop or stack the system board.
• If you put a system board down, be sure to put it only on a padded surface such as an ESD mat or
a corrugated conductive material.
10
8
9
Color Torque
Black 0.196 Nm
(2 kgf-cm)
.
Chapter 7 Removing or replacing a FRU
71