Troubleshooting Method - Toshiba MCY-MUG0401HSW-E Service Manual

9-2. Troubleshooting method

The remote controllers (main remote controller and central control remote controller) and the interface P.C. board
of an outdoor unit are provided with an LCD display (remote controller) or a 7-segment display (outdoor interface
P.C. board) to display operational status. Using this self-diagnosis feature, the fault site / faulty part may be
identified in the event of a fault by following the method described below.
The list below summarizes check codes detected by various devices. Analyze the check code according to where it is displayed and work out
the nature of the fault in consultation with the list.
• When investigating a problem on the basis of a display provided on the indoor remote controller or central remote controller See the "Remote
control or main remote controller display" section of the list.
• When investigating a problem on the basis of a display provided on an outdoor unit - See the "Outdoor 7-segment display" section of the list.
• When investigating a problem on the basis of a wireless remote controller-controlled indoor unit - See the "Light sensor indicator light block"
section of the list.
List of Check Codes (Indoor Unit)
(Check code detected by indoor unit)
Check code
central control Outdoor 7-segment display
or main remote
controller
Sub-code
display
E03 – –
E04 – –
E08 E08 Duplicated indoor address
E10 – –
E11 – –
E17 – –
E18 – –
F01 – –
F02 – –
F03 – –
F10 – –
F11 – –
F29 – –
F30 – –
J29 – –
Detected indoor unit
address
J30 J30 *Not displayed
depending on the DN
code (I.DN) setting
J31 – –
L03 – –
L07 – –
Display of receiving unit
Indicator light block
Typical problem site
Operation Timer Ready
Flash
Indoor-remote controller periodic
communication trouble
Indoor-outdoor periodic communication
trouble
Duplicated indoor address
Indoor inter-MCU communication
trouble
Communication check code
between Application control
kit and indoor unit
Communication trouble
between indoor unit (s) and
Shut-off Valve unit(s)
Trouble in periodic
communication between indoor
header and follower unit
Indoor heat exchanger temperature
ALT
sensor (TCJ) trouble
Indoor heat exchanger temperature
ALT
sensor (TC2) trouble
Indoor heat exchanger temperature
ALT
sensor (TC1) trouble
Room air temperature sensor (TA/TSA)
ALT
trouble
Discharge air temperature sensor (TF/
ALT
TFA) trouble
SIM P.C. board or other indoor trouble
Occupancy sensor trouble
SIM Leak Detector Trouble
SIM Refrigerant leak detection
Refrigerant leak detection
SIM sensor exceeding its life
of the product
Duplicated indoor group
SIM
header unit
Connection of group control cable to
SIM
stand-alone indoor unit
162
: Lighting, : Flashing, : Goes off
ALT: Flashing is alternately when there are two flashing LED
SIM: Simultaneous flashing when there are two flashing LED
Description of Check code
Communication from remote controller or network adaptor
has been lost (so has central control communication).
Signals are not being received from outdoor unit.
Indoor unit detects address identical to its own.
MCU communication between main controller and motor
microcontroller is failure.
Communication check code between Application
control kit and indoor unit P.C. board.
There is no communication from Shut-off Valve unit(s)
Periodic communication between indoor header and follower
units cannot be maintained.
Heat exchanger temperature sensor (TCJ) has been open /
short-circuited.
Heat exchanger temperature sensor (TC2) has been open /
short-circuited.
Heat exchanger temperature sensor (TC1) has been open /
short-circuited.
Room air temperature sensor (TA/TSA) has been open /
short-circuited.
Discharge temperature sensor (TA/TFA) has been open /
short-circuited.
Open/Short-circuit of indoor air suction temperature sensor
(TRA) was detected.
There is no signal from Occupancy sensor
• There is no communication from Leak Detector
• A Malfunction signal received from Leak
Detector.
Leak Detector detects refrigerant leak
Energization time of the Leak Detector has
reached its useful life.
There is more than one header unit in group.
There is at least one stand-alone indoor unit to which group
control cable is connected.