Remove The Coin-Cell Battery - Lenovo IdeaPad 3 Series Hardware Maintenance Manual

"Remove the lower case" on page 32
"Remove the system fan" on page 46
"Remove the USB board" on page 50
Step 1. Remove the USB board cable.
Figure 39. Remove the USB board cable
Go to https://support.lenovo.com/partslookup
replacement parts:
USB board cable

Remove the coin-cell battery

Make sure the following FRUs (or CRUs) have been removed.
"Remove the lower case" on page 32
Step 1. Disconnect the battery pack cable from the system board.
Attention: Use your fingernail to pull the connector to unplug it. Do not pull the cable.
to look up the Lenovo part numbers of the following
.
Chapter 4 Removing a FRU or CRU
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