Mitsubishi Electric MXZ-SM72TAM-U1 Service Manual page 45

1501 (U2): Refrigerant shortage trouble
Diagnosis of failure
Continued from the previous page.
Is the resistance detected?
Check the 63HS voltage.
Is the voltage(*) detected?
Check the voltage and appearance of the
outdoor multi controller circuit board.
Is the voltage normal value?
Is it free from any trace of overheating
or burning?
Disconnect the indoor LEV wiring and check the
resistance.
Is the resistance detected?
*For the voltage, refer to "How to check the components".
OCH800A_45
No
Yes
No
Yes
No
Yes
No
Yes
Replace the thermistor.
Replace the 63HS.
Replace the outdoor multi controller circuit
board.
Replace the indoor LEV.
Replace the indoor controller board.
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