Canon MultiPASS MP390 Service Manual page 72

Chapter 3
(7) Remove the screw (c) and then remove the Power supply unit.
F-3-26
Removing the Power supply unit (MP390 only)
Please make sure to attach the Power supply unit to the main unit only after connecting a grounding cable to the unit.
If a grounding cable is connected to the Power supply unit after the Power supply unit is attached to the main unit, it
may damage the Power supply unit with electrical stress.
3-21
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