Mitsubishi Heavy Industries FDT28KXE6A Service Manual page 57

Error code
None
Remote controller:
7-segment display:
1. Applicable model
All models
2. Error detection method
3. Condition of error displayed
4. Presumable cause
• Wrong connection or breakage
of connecting wires
• Blown fuse
• Transformer anomaly
• Indoor power PCB anomaly
• Broken harness
• Indoor control PCB anomaly
Note:
LED Green Red
Stays Off Stays Off
Indoor
Stays Off 2 time flash
Outdoor
5. Troubleshooting
Diagnosis
Is
AC 220-240V/220V
detected between L-N on
the indoor terminal
block?
YES
Note (1)
FDT and FDTC series: F200, F201
Other than FDT and FDTC: Fuse between wires
(1)
Are fuses OK?
(2 pcs)
YES
Other than FDT and FDT and FDTC series
FDTC series
Is DC18V or higher
detected between Red-
Red (CNW2) at the
transformer secondary
side?
55
–
Power supply system anomaly
Content
(Power supply to indoor unit PCB)
NO
Is AC
380/415 V for 3-phase
unit detected between L1, L2, and L3 on
the outdoor terminal block
respectively.
NO
(2)
Is power
supply between ➀ - ➂ of
CNW0 OK?
Note (2)
Remove
YES transformer for
other than FDT and
FDTC series (CNW1)
(3)
Is power
supply to FM, LM and etc.
OK?
Note (3) LM: Louver motor
FM: Fan motor
(4)
Is
DC5V detected
between ➃ - ➄ of
CNW2?
Note (4)
➄
–
Countermeasure
Outdoor Noise filter PCB
NO
anomaly  Replace it
Wrong wiring or broken
YES
wires between outdoor and
indoor units
Indoor power PCB
NO
anomaly  Replace it
Replace FM, LM and etc.
YES
Replace fuse
NO
Indoor power PCB anomaly
NO
 Replace it
for GND
Indoor control PCB
YES
anomaly  Replace it
Replace transformer
NO
Indoor control PCB
YES
anomaly  Replace it