Toshiba MMY-MAP0804FT7(Z), Service Manual, Page: 188 / 333

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Check code
Location
of
detection
System status Description
Error detection
condition(s)
Check items (locations)
Outdoor 7-segment display Main
remote
controller
Check
code
Sub-code
L31 — —
I/F Continued
operation There is part failure
in P.C. board (I/F). Check outdoor P.C. board (I/F). Extended IC error
P03
—
P03
I/F All stop Discharge
temperature (TD1)
exceeds 115˚C. • Check outdoor service valves (discharge
gas side, suction gas side, liquid side) to
confirm full opening.
• Check outdoor PMVs (PMV1, 2, 4) for
clogging.
• Check resistance characteristics of TD1
sensor.
• Check for insufficiency in refrigerant
quantity.
• Check for defect in 4-way valve.
• Check for leakage of SV4 circuit.
• Check SV4 circuit (wiring or installation
error in SV41, SV42 or SV43).
• Check SV5 circuit leakage.
• Check SV6 circuit leakage.
(Capillary clogging, valve operation error)
• Check mispiping of discharge/suction gas
main pipes.
• Check Cool/Heat FS unit.
SVD valve, SVS valve leakage check
(SVDD valve, SVSS leakage check)
Mispiping of FS unit connecting pipe
(suction gas/discharge gas)
Check connection of connector between
FS unit and indoor unit.
Check miswiting between SVS and SVD
valve. Discharge
temperature
TD1 error
P04 P04
IPDU 01: Compressor
1 side
02: Compressor
2 side
03: Compressor
3 side All stop High-pressure SW is
activated. • Check connection of highpressure SW
connector.
• Check for defect in Pd pressure sensor.
• Check outdoor service valves (discharge
gas side, suction gas side, liquid side) to
confirm full opening.
• Check for defect in outdoor fan.
• Check for defect in outdoor fan motor.
• Check outdoor PMVs (PMV1, 2, 4) for
clogging.
• Check indoor/outdoor heat exchangers
for clogging.
• Check for short-circuiting of outdoor
suction/discharge air flows.
• Check 4-way valve error.
• Check SV11 circuit.
(Valve operation error)
• Check checked valve of discharge gas
pipe for error.
• Check SV2 circuit for clogging.
• Check for defect in outdoor P.C. board
(I/F).
• Check for error in indoor fan system
(possible cause of air flow reduction).
• Check opening status of indoor PMV.
• Check indoor-outdoor communication
line for wiring error.
• Check for faulty operation of check valve
in discharge pipe convergent section.
• Check gas balancing SV4 valve circuit.
• Check SV5 valve circuit.
• Check for refrigerant overcharging.
• Check mispiping of discharging gas/
suction gas main pipes.
• Check circuit clogging at liquid side of
auxiliary heat exchanger.
(PMV4, checked valve)
• Check FS unit.
Check SVD valve clogging and operation
error.
Check wiring inside of FS unit.
(SVD/SVS coil miswiring, etc.)
Check wiring between FS unit and indoor
unit. (Mistaken wiring, wire disconnection,
wiring forgotten) Activation of high-
pressure SW
— — P01
Indoor unit Stop of
corresponding
unit • Check the lock of fan motor (AC fan).
• Check wiring. Indoor fan motor
error
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