Mitsubishi Electric PUMY-P200YKM2 Technical & Service Manual page 58

Check code
4210
(UP)
●Diagnosis of defects
Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards.
Continued from the previous page.
Are they connected properly?
Check the operation of indoor/outdoor fan
motors.
Does it operate normally?
Check for indoor/outdoor short-cycle.
Are those units short-cycled?
Disconnect the compressor wiring from the outdoor
power board, then check the voltage among each
phases U, V and W during test run (SW7-1 ON).
Are the voltage among the phases
U-V, V-W and W-U different?
Replace the outdoor controller board.
Does it operate normally?
OCH675D
Compressor overcurrent interruption
Diagnosis
Yes
Yes
(short-cycled)
No (no short-cycled)
Make sure to perform a voltage
check with the same performing
frequencies.
Yes
Yes
Connect the compressor wiring (U, V and
W phase) properly, then turn the power
No
back ON.
No
Yes
Remove factor(s) causing the short-cycle.
No
Replace the outdoor power board.
No
58
Chart 2 of 2
Remedy
Check the DC fan motor.
Replace the compressor.
Complete.