Toshiba SUPER MMK-AP0073H (IN) Service Manual page 113

Check code
[P04] / [21]
(Current code / AI-NET)
Sub-code: 01: Compressor 1 side 02: Compressor 2 side
Does high-pressure SW operate?
YES
Are parts of high-pressure SW normal?
YES
Is service valve fully opened?
YES
Reset power supply, and start a test
operation corresponded to the season.
Are characteristics of
high-pressure sensor normal?
B Cooling operation
Does cooling outdoor fan
normally operate?
YES
Is there a cause to interfere operation
of heat exchanger of outdoor unit?
1. Heat exchanger clogging
2. Air short circuit
NO
Is SV2 circuit normal?
YES
A
Check code name
Actuation
of high-pressure SW
NO
Is circuit cabling normal?
NO
NO
Cooling → To B
Heating → To C
NO
NO
Is there no crack or
coming-off of fan?
YES
NO
Cause of operation
1. High-pressure SW error
2. Service valve closed
3. Pd sensor error
4. Indoor/outdoor fan error
5. Indoor/outdoor PMV choke
6. Indoor/outdoor heat exchanger clogging, air short circuit
7. SV2 circuit error
8. SV4 circuit error
9. SV5 circuit error
10. Discharge line check valve malfunction
11. Refrigerant overcharge
Note) High-pressure SW is normally closed.
(B contact)
NO
YES
NO
YES
113
Check and correct cabling.
Check parts.
Failure → Replace
Open service valve fully.
Check I/F P.C. board.
Failure → Replace
Replace the high-pressure sensor.
Repair faulty parts.
Connector connection,
fan IPDU, fan motor, wiring
Eliminate the interfered causes.
Repair SV2 circuit.
(
Coil error, clogging,
disconnection of wiring, etc.
)