Troubleshooting - Toshiba MMU-P0121H Service Manual

3-6. TROUBLESHOOTING

3-6-1. Check Method
On the remote controller and interface unit of the outdoor unit, the CHECK display LCD (Remote controller) or 7
segment LED (on microprocessor control P.C. board) an operation display is provided. Observing this display,
you can understand the operation status. The method to judge an error/fault by using this self-diagnostic func-
tion is described below.
STANDBY
display
Over capacity
Abnormal phase connection
Indoor drain overflow alarm
Remote controller
Remote
Remote controller serial signal circuit
controller
ndoor sensor (TA) short circuit
Indoor heat exchanger sensor (TC1) short circuit
Indoor heat exchanger sensor (TC2) short circuit
Indoor pressure sensor short circuit
Indoor
Motor short circuit
unit
Drain pump fault
Refrigerant circulation amount shortage judgment
Indoor/outdoor communication short circuit
Central management communication short circuit
Central management address set up fault
External input display fault
External interlock display fault
Group operation fault
Indoor unit miswiring/misconnection
Indoor P.C. board short circuit
Communication circuit between indoor MCU
(For 4DC only)
outdoor
High pressure SW circuit
unit
G-Tr short-circuit protective operation
Current detection circuit
Compressor error
Compressor break down
TH sensor circuit
Heat sink overheat protective operation
Liquid crystal remote controller CHECK code
"99"
Indoor unit
"0C"
"93"
"94"
"b9"
"11"
"0b"
"9F"
"95"
"97"
"98"
"b5"
"b6"
"b7"
"9A"
"12"
"CF"
Outdoor IPDU
NOTE :
* : No display on
remote controller
Outdoor unit interface segment check code
Master outdoor unit
Inverter serial signal short circuit
Outdoor heat exchanger sensor (TE1) short circuit
Discharge temp. sensor (TD1) short circuit
Discharge temp. sensor (TD2) short circuit
Suction temp.sensor (TS) short circuit
High pressure sensor (Pd) short circuit
Low pressure sensor (Ps) short circuit
Pressure sensor (Pd/Ps) miswiring
Discharge temp. (TD1) protective operation
Discharge temp. (TD2) protective operation
Low Hz time discharge temp. (TD1) protective operation
Suction temp. (TS) protective operation
High pressure (Pd) protective operation
Low pressure (Ps) protective operation
Fixed-speed 1 high pressure SW short circuit
Fixed-speed 2 high pressure SW short circuit
Fixed-speed 1 IOL, OCR short circuits
Fixed-speed 2 IOL, OCR short circuits
Inverter IOL short circuit
Mg-SW deposit controlling display
Outdoor unit power supply phase order miswiring
Extension IC, EEPROM short circuit
Indoor/outdoor error
4-way valve reversal alarm
Indoor/outdoor communication short circuit
No.of connected indoor units over capacity
Connected indoor units over capacity
Reduction of No. of server outdoor units
"21"
No. of server outdoor units over capacity
"14"
Server outdoor address incorrect
"17"
Outdoor master unit incorrect
"1d"
Server outdoor unit error
"1F"
Oil temp. (TK1) sensor short circuit
"d3"
Oil temp. (TK2) sensor short circuit
"dA"
Oil temp. (TK3) sensor short circuit
Oil level low detection
Oil temp. (TK1) detection error
Oil temp. (TK2) detection error
SV3C valve blockage detection
SV3C valve leakage detection
Outdoor refrigerant leakage detection
Indoor address undefined *
Outdoor address undefined *
Backup operation stop
3-38
Server
outdoor
unit
"04" —
"18" "18"
"A0" "A0"
"A1" "A1"
"A2" "A2"
"AA" "AA"
"b4" "b4"
"Ab" "Ab"
"A6" "A6"
"bb" "bb"
"AE" "AE"
"A7" "A7"
"22" "22"
"bE" "bE"
"E1" "E1"
"F0" "F0"
"E6" "E6"
"F1" "F1"
"E5" —
"bd" "bd"
"AF" "AF"
"1C" "1C"
"Eb" —
"08" "08"
"95" —
"96" —
"89" —
"8d" —
"8E" —
"8F" —
"d1" "d1"
"d2" —
"d4" "d4"
"d5" "d5"
"d6" "d6"
"d7" "d7"
"d8" "d8"
"d9" "d9"
"db" "db"
"dC" "dC"
"dd" "dd"
"dE" —
"dF" —
"8C" —