Mitsubishi Heavy Industries SRK25GZ-L1 Handbook page 219

(6) Indoor electrical components inspection flowchart
Is there voltage between terminal
blocks 1 and 2 ? (AC 220/240 V)
YES
Is the fuse burnt out? (3.15 A)
YES
Is there voltage between CNC (1)
and (2) on the secondary side of the
transformer? (Approx. 12 V)
YES
Is the voltage between terminal
blocks 2 and 3 oscillating between
DC 0 and 12V?
YES
Indoor electrical components
are normal.
NO
Inspect power source
for outdoor unit.
NO
Replace fuse.
NO
Replace the transformer.
NO
Replace printed
circuit board.
SCM-HG (2 room)
217