Toshiba MMD- AP0724H2UL, Service Manual

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MG-CTT: Magnet contactor
Check code
Location
of
detection
Description
System
status
Error detection
condition(s)
Check items (locations) Main
remote
controller
Outdoor 7-segment display
Check code Sub-code
P04 P04
01: Compressor
1 side
02: Compressor
2 side
03: Compressor
3 side IPDU Activation of high-
pressure SW All stop High-pressure SW is
activated. • Check connection of high-
pressure SW connector.
• Check for defect in Pd
pressure sensor.
• Check outdoor service valves
(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) for clogging.
• Check indoor/outdoor heat
exchangers for clogging.
• Check for short-circuiting of
outdoor suction/discharge air
flows.
• 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.
P05 P05
00: I/F Detection of open
phase/phase sequence All stop • Open phase is
detected when
power is turned
on.
• Inverter DC
voltage is too high
(overvoltage) or
too low
(undervoltage).
• Check for defect in outdoor
P.C. board (I/F).
01: Compressor
1 side
02: Compressor
2 side
03: Compressor
3 side Inverter DC voltage
(Vdc) error
(compressor)
MG-CTT error
P07 P07
01: Compressor
1 side
02: Compressor
2 side
03: Compressor
3 side IPDU
I/F Heat sink overheating
error All stop Temperature sensor
built into IGBT (TH)
is overheated. • Check power supply voltage.
• Check outdoor fan system
error.
• Check heat sink cooling duct
for clogging.
• Check IGBT and heat sink for
thermal performance for faulty
installation.
(e.g. mounting screws and
thermal conductivity)
• Check for defect in A3-IPDU.
(faulty IGBT built-in
temperature sensor (TH))