Lenovo 21JK Hardware Maintenance Manual page 85

• 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 surface.
• Avoid bending a system board and hard pushing to prevent cracking at each BGA (Ball Grid Array)
chipset.
For access, remove these FRUs in order:
• "1010 Base cover assembly" on page 62
• "1040 M.2 solid-state drive" on page 66
• "1060 Wireless LAN card" on page 68
• "1020 Built-in battery" on page 65
• "1070 Thermal fan assembly" on page 69
This computer shares a common system board with another computer. After replacing the system board,
you will be prompted to input a brand name to correctly identify the machine type. The following table
contains the brand name required to complete this step.
Note: Input the exact brand name as shown in this table.
Product name
ThinkPad E14 Gen 5
ThinkPad E16 Gen 1
Removal steps of the system board
ThinkPad E14 Gen 5
Note: The new system board does not come with a new M.2 solid-state drive thermal pad, it is suggested
that you order an extra thermal pad in case the old thermal pad is damaged during replacement.
Machine type (MT)
21JR, 21JS, 21JK, and 21JL
21JT, 21JU, 21JN, and 21JQ
.
Chapter 8 Removing or replacing a FRU
79