Toshiba MMU-P0121H Service Manual page 63

Check code
[12]
Other indoor alarm
Is there no irregularity
of power supply?
NO
Indoor main P.C. board check
Defective Replacement
Check code
G-Tr short circuit protective system alarm
Is power supply voltage
of outdoor unit normal?
YES
Is connection of
wiring connector on IPDU
P.C. board normal?
YES
Is AC 20A fuse working?
YES
Is inverter compressor normal?
YES
Is smoothing capacitor normal?
(2200µF, 400V x 2)
YES
Check IPDU P.C. board.
1. Irregularity of power supply
2. Noise of peripheral equipment
3. Indoor main P.C. board failure
YES
[14]
NO
NO
NO
NO
NO
Operation cause
Operation cause
1. Outdoor unit power supply error
2. Wiring error on IPDU P.C. board
3. AC fuse disconnection
4. Inverter compressor error
5. Defective IPDU P.C. board
Modify power supply line.
Modify connector of wiring.
Replace IPDU P.C. board and fuse.
Replace IPDU P.C. board
and inverter compressor.
Check capacity decrease and appearance.
Replace IPDU P.C. board.
3-60
Check power supply voltage,
modify lines, remove noise, etc.