Mitsubishi Electric MR-J4-10B(-RJ) Instruction Manual page 376

11. OPTIONS AND PERIPHERAL EQUIPMENT
(4) Replacement procedure of the built-in battery
When the MR-BAT6V1SET reaches the end of its life, replace the MR-BAT6V1 battery in the MR-
BAT6V1SET.
Cover
MR-BAT6V1
1) While pressing the locking part, open the cover.
Locking part
2) Replace the battery with a new MR-BAT6V1.
3) Press the cover until it is fixed with the projection of
the locking part to close the cover.
Projection
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