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1) Failure diagnosis flowchart
Are error codes flashing?
“E2” “E3” “E4” “E5” “E6” “E7”
“A1” “A2” “A3” “A6” “A9”
“F1” “F2” “F5” “F7”
Does the power lamp light
by turning the power on?
Does the detective buzzer beep
by turning the power on?
Is “full lamp” lighting?
NO
YES
NO
NO
OK
OK
OK
OK
OK
OK
OK
OK
OK
YES
YES
NO
Drain water from the tank.
NG
NG
NG
YES
OK
OK
OK
NO
NG
Refer to “Error Indications and Corrective
Actions,” and follow the procedures.
Check the continuity of power cord.
Is the tank filled with water ?
Replace power control board.
Replace operation control board.
NG
NG
NG
OK
OK
OK
OK
Check the current fuse of
power control board (6.3A/250V).
Check if there is no disconnection or
contact failure of the connector (P2) and
connector pins of power control board.
Check if there is no disconnection or
contact failure of the connector (P3) and
connector pins of power control board.
Replace heater fuse.
NG
OK
Check the resistance of the heater fuse.
Normal : short
Abnormal : open
Check the resistance of frame fuse.
Normal : short
Abnormal : open
Check the float.
NG
OK
OK
OK
Check the float.
●
Is the float switch coming off
or attached upside-down?
●
Is the float movement smooth?
●
Is a magnet attached to the float?
NG
YES
Check if there is no disconnection
or contact failure of the connectors
(P10 and P21) of power control board
are securely joined to the connectors
(P20 and P31) of operation control board.
(Verify that no connector pin is off.)
Check if connectors are securely
connected.
Insert the connectors and connector
pins securely.
Replace power control board.
Replace operation control board.
Replace power control board.
Replace operation control board.
Replace operation control board.
Insert the connector and
connector pins securely.
Insert the connector and
connector pins securely.
NG
OK
Replace frame fuse.
NG
OK
NG
OK
OK
NG
OK
Check if the lamp of operation panel light.
*
How to put out all lighting (Press the dehumidifying
switch and the mode switch together 4 times
when the power is off.
Turn on the power within 2 seconds.)
Check if LED on the operation
control board is down.
(When LED is down, correct it.)
NG
Replace power control board.
Replace operation control board.
Replace power control board.
11. Troubleshooting procedure
Replace the power cord.
17
Summary of Contents for MJ-EZ6CX-S1-IT
Page 50: ...Issued in 2010 7 ...