Mitsubishi Electric CMB-WM108V-AA Service Handbook page 205

[ VIII Troubleshooting ]
Check for conductivity between TB12 and pin 1 of
CN1 and between TB14 and pin 3 of CN1.
Check the wiring between the noise filter board and
TB1 of power-supply board, and also check
connectors L2-N of TB1, TB12, and TB14. for proper
connections.
Check the voltage across L2 and N of power supply
terminal block TB1.
HWE1708A
A
Is there conductivity between them?
YES
Any problems with wiring or
loose connectors?
NO
198-264 VAC
NO
NO
Replace the noise filter board.
YES
Correct wiring problems, and tighten loose connectors.
YES
Replace the power-supply board.
Check the power-supply wiring and the main
power supply, and correct any problems found.
- 196 -
B
Turn the power
supply back on.
GB