Mitsubishi Heavy Industries FDT90VNPWVH Service Manual page 74

Error code
None
Remote control:
1. Applicable model
All models
2. Error detection method
3. Condition of Error displayed
4. Presumable cause
• Misconnection or breakage of
connecting wires
• Blown fuse
• Faulty transformer
• Faulty indoor unit control or
power PCB
• Broken harness
• Faulty outdoor unit PCB
Note:
LED Green Red
Indoor Stays OFF Stays OFF
5. Troubleshooting
Diagnosis
Is
AC220-240V
detected between and
on the terminal block
of indoor
unit?
YES
Note(1) FDT, FDE: F1, F2
FDU, FDUM: F1
(1)
Are fuses OK
YES
(1)
Is DC5V
detected between -
of CNW2?
Note (1)
YES
Is JX1 open?
73
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Content
Power source system error
(Power source to indoor unit control PCB)
NO
Is
AC220-240V
detected between
and 2/N on the terminal
block of outdoor
unit?
YES
NO
Is the
check of resistance between
- of CNW0
OK?
YES
Is the
checked result
of resistance of FM,
LM, etc
OK?
YES
NO
for GND
NO
YES
-
'19 • PAC-SM-334
Countermeasure
Defective outdoor unit PCB
NO
Misconnection or breakage
of connecting wires
Defective indoor unit
NO
control or power
PCB ➞ Replace.
Replace FM, LM, etc.
NO
Replace fuse.
Defective indoor unit
power PCB ➞ Replace.
Open JX1.
Defective indoor unit
control PCB ➞ Replace.