Mitsubishi Electric PUHZ-SW75VAA-SC Service Manual page 22

9-2. SELF-DIAGNOSIS ACTION TABLE
<Abnormalities detected when the power is turned on>
Abnormal point and detection method
Check code
None
63L connector open (SW100/SHW80/
SHW112 only)
Abnormal if 63L connector circuit is open for
3 minutes continuously after power supply.
63L: Low pressure switch
F3
(5202)
63H connector open
Abnormal if 63H connector circuit is open for
3 minutes continuously after power supply.
63H: High pressure switch
F5
(5201)
OCH651A
1 No voltage is supplied to terminal
block (TB1) of outdoor unit.
a) Power supply breaker is
turned off.
b) Contact failure or
disconnection of power
supply terminal
c) Open phase (L or N phase)
2 Electric power is not charged
to power supply terminal of
outdoor power circuit board.
a) Contact failure of power
supply terminal
b) Open phase on the outdoor
power circuit board
3 Electric power is not supplied
to outdoor controller circuit
board.
— a) Disconnection of connector
(CNDC)
4 Disconnection of reactor (DCL
or ACL)
5 Disconnection of outdoor noise
filter circuit board or parts failure
in outdoor noise filter circuit
board
6 Defective outdoor power circuit
board
7 Defective outdoor controller
circuit board
1 Disconnection or contact failure
of 63L connector on outdoor
controller circuit board
2 Disconnection or contact failure
of 63L
3 63L is working due to
refrigerant leakage or defective
parts.
4 Defective outdoor controller
circuit board
1 Disconnection or contact failure
of 63H connector on outdoor
controller circuit board
2 Disconnection or contact failure
of 63H
3 63H is working due to defective
parts.
4 Defective outdoor controller
circuit board
Note: Refer to indoor unit section for code P, code E, and Code L.
Cause
1 Check following items.
a) Power supply breaker
b) Connection of power supply terminal block
(TB1)
c) Connection of power supply terminal block
(TB1)
2 Check following items.
a) Connection of power supply terminal block
(TB1)
b) Connection of terminal on outdoor power
circuit board
Check connection of the connector LI or NI.
Refer to "9-6.TEST POINT DIAGRAM".
3 Check connection of the connector (CNDC)
on the outdoor controller circuit board.
Check connection of the connector, CNDC
on the outdoor power circuit board(V)/the
noise filter(Y). Refer to "9-6.TEST POINT
DIAGRAM".
4 Check connection of reactor. (DCL or ACL)
Refer to "9-6.TEST POINT DIAGRAM".
5 a) Check connection of outdoor noise filter
circuit board.
b) Replace outdoor noise filter circuit board.
Refer to "9-6.TEST POINT DIAGRAM".
6 Replace outdoor power circuit board.
7 Replace controller board (When items above
are checked but the units cannot be repaired).
1 Check connection of 63L connector on
outdoor controller circuit board.
Refer to "9-6.TEST POINT DIAGRAM".
2 Check the 63L side of connecting wire.
3 Check refrigerant pressure.
Charge additional refrigerant.
Check continuity by tester.
Replace the parts if the parts are defective.
4 Replace outdoor controller circuit board.
1 Check connection of 63H connector on
outdoor controller circuit board.
Refer to "9-6.TEST POINT DIAGRAM".
2 Check the 63H side of connecting wire.
3 Check continuity by tester.
Replace the parts if the parts are defective.
4 Replace outdoor controller circuit board.
22
Judgment and action