Troubleshooting Procedure - Mitsubishi Electric MJ-E14EG-S1-IT Service Manual

9. Troubleshooting procedure

1) Failure diagnosis fl owchart
Do any of the following
errors appear on the
humidity indicator?
"E0" "E1" "E2" "E3" "E4"
"E5" "E7" "E8" "A1" "A2"
"A6" "A8" "P4"
NO
CHILD LOCK indicator
turns on
NO
When the POWER switch is
turned ON, does the operating
mode lamp turn on?
YES
Does the detection buzzer
beep when the POWER
switch is turned ON?
YES
Is the FULL lamp lit?
NO
A
10
Perform the recommended
actions described in "Error
YES
Indications and Corrective
Actions" on page 16.
YES
YES
Deactivate the child lock
YES
NO
Check the power cord conduction
OK
Check the continuity of current
fuse on the power supply board
FUSE1 : 10A FUSE2/3 : 2A
OK
Check if the lamps on the
NO
control panel turn on.
* How to turn on all of the
lamps (See "LED and
Monitor indicators" on
page 17)
* Check whether any of the
LEDs on the operation
control board have fallen
off (repair if an LED has
fallen off)
OK
YES
Is the tank full?
NO
Float check:
• Is the fl oat switch disconnected
or installed reversely?
• Is the fl oat operation smooth?
• Is there a magnet attached
to the fl oat?
OK
Check the fl oat switch
• Check the control board
P12 connector insertion
and the connector pins
• Check the continuity
between the P12
connector terminals when
the water tank is installed
Normal . . . When tank is
full: shorted
When tank is empty: open
OK
NG
Replace the power cord
NG
Replace the power
supply board
Check that the power
NG
supply board, control
board and operation
control board connectors
are fi rmly connected
(carefully check whether
any of the connector pins
have been pulled out,
etc.).
YES
Drain the water from the tank
NG
NG
Repair the fl oat problem
NG
NG
Replace the fl oat switch
NG
Replace the control board
NG
Replace the power
supply board
OK
OK
OK
Firmly insert the
NG
connectors or
connector pins in
the trouble spots
NG
Replace the operation
control board
NG
Replace the control
board
NG
Replace the power
supply board
OK
OK
OK
OK
OK