Troubleshooting Method - Toshiba MCY-MHP0404HT-C 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 fault on the basis of a display provided on the indoor remote controller or TCC-LINK central control remote controller -
See the "TCC-LINK remote controller or main remote controller display" section of the list.
• When investigating a fault on the basis of a display provided on an outdoor unit - See the "Outdoor 7-segment display" section of the list.
• When investigating a fault 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)
(Error detected by indoor unit)
Check code
TCC-LINK Outdoor 7-segment display
central control
or main remote
Sub-code
controller
display
E03 – –
E04 – –
E08 E08 Duplicated indoor address
E10 – –
E18 – –
F01 – –
F02 – –
F03 – –
F10 – –
F11 – –
F29 – –
L03 – –
L07 – –
L08 L08 –
L09 – –
L20 – –
L30 L30 Detected indoor unit No.
P01 – –
P10 P10 Detected indoor unit No.
P12 – –
P31 – –
Display of receiving unit
Indicator light block
Operation Timer Ready
Flash
Indoor-remote controller periodic
communication error
Indoor-outdoor periodic communication
error
Duplicated indoor address
Indoor inter-MCU communication error
Error in periodic communication
between indoor header and follower
unit
Indoor heat exchanger temperature
ALT
sensor (TCJ) error
Indoor heat exchanger temperature
ALT
sensor (TC2) error
Indoor heat exchanger temperature
ALT
sensor (TC1) error
ALT Ambient temperature sensor (TA) error
Discharge temperature sensor (TF)
ALT
error
SIM P.C. board or other indoor error
SIM Duplicated indoor group outdoor unit
Connection of group control cable to
SIM
stand-alone indoor unit
SIM Indoor group address not set
SIM Indoor capacity not set
SIM Duplicated central control address
SIM Indoor external error input (interlock)
ALT Indoor AC fan error
ALT Indoor overflow error
ALT Indoor DC fan error
ALT Other indoor unit error
109
IPDU: Intelligent Power Drive Unit (Inverter P.C. board)
: Lighting,
ALT: Flashing is alternately when there are two flashing LED
SIM: Simultaneous flashing when there are two flashing LED
Typical fault site
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 faulty.
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.
Ambient temperature sensor (TA) has been open / short-
circuited.
Discharge temperature sensor (TF) has been open / short-
circuited.
Indoor EEPROM is abnormal (some other error may be
detected).
There is more than one outdoor unit in group.
There is at least one stand-alone indoor unit to which group
control cable is connected.
Address setting has not been performed for one or more
indoor units (also detected at outdoor unit end).
Capacity setting has not been performed for indoor unit.
There is duplication in central control address setting.
Unit shutdown has been caused by external error input
(CN80).
Indoor AC fan error is detected (activation of fan motor
thermal relay).
Float switch has been activated.
Indoor DC fan error (e.g. overcurrent or lock-up) is detected.
Follower unit cannot be operated due to outdoor unit alarm
(E03 / L03 / L07 / L08).
97
: Flashing, : Goes off
Description of error