Toshiba MMU-UP0051MH-E(TR) Service Manual page 104

Check code
Main Outdoor 7-segment display
remote
Check
Sub-code
controller
code
No. of indoor
units from
which signal is
received
normally
E04/E06 E06
— E07 —
Duplicated
indoor address
E08 E08
E09 — —
E10 — —
01:
Indoor-outdoor
communication
02:
Outdoor-outdoor
E12 E12
communication
E15 E15 —
Location
Description
of
detection
Indoor unit Indoor-outdoor All stop
communication
circuit trouble
(E04)
I/F Dropping out of
indoor unit
(E06)
I/F Indoor-outdoor All stop
communication
circuit trouble
(detected at
outdoor end)
Indoor unit Duplicated All stop
I/F indoor address
Remote Duplicated Stop of
controller master remote corresponding
controller unit
Indoor unit Indoor inter- Stop of
MCU corresponding
communication unit
trouble
I/F Automatic All stop
address starting
trouble
I/F Indoor unit not All stop
found during
automatic
address setting
– 104 –
Check code detection
System status
condition(s)
Condition 1
One indoor unit or more
initially communicating
normally fails to return signal
for specified length of time.
Condition 2
Outdoor I / F board
SW103, Bit4 : ON
(To switch the check code
detection condition.)
Display on main remote
controller.
Indoor units unavailable for
indoor / outdoor
communication. :E04
Indoor units available for
indoor / outdoor
communication. : E06
In TU2C-LINK
communication system, if
the termination resistance is
not set in any of the indoor
units.
Signal cannot be transmitted
from outdoor to indoor units
for 30 seconds continuously.
More than one indoor unit
are assigned same address.
In two remote controller
configuration (including
wireless), both controllers
are set up as master.
(Header indoor unit is shut
down with alarm, while
follower indoor units
continue operating.)
Communication cannot be
established/maintained upon
turning on of power or
during communication.
• Indoor automatic address
setting is started while
automatic address setting
for equipment in other
refrigerant line is in
progress.
• Outdoor automatic
address setting is started
while automatic address
setting for indoor units is in
progress.
Indoor unit cannot be
detected after indoor
automatic address setting is
started.
Check items (locations)
• Check power supply to
indoor unit.
(Is power turned on?)
• Check indoor-outdoor
power-on sequence.
• Check indoor address
setting
• Check wiring of Indoor-
outdoor communication
wires
• Check outdoor terminator
resistor setting (SW100,
SW103
Bit 2).
ON
• Check power supply to
1 2 3
indoor unit.
4
(Is power turned on?)
• Check connection of
indoor-outdoor
communication cable.
• Check connection of
communication connectors
on indoor P.C. board.
• Check connection of
communication connectors
on outdoor P.C. board.
• Check for failure in indoor
P.C. board.
• Check for failure in outdoor
P.C. board (I/F).
• Check outdoor terminator
resistor setting (SW100,
Bit 2).
• Check connection of
indoor-outdoor
communication circuit.
• Check indoor addresses.
• Check for any change
made to remote controller
connection (group/
individual) since indoor
address setting.
• Check remote controller
settings.
• Check remote controller
P.C. boards.
• Check for failure in
indoor P.C. board
• Check whether the outdoor
unit of other systems or the
indoor unit is connected to
Uv (U1/U2) line or Uc
(U5/U6) line.
• Perform automatic address
setting again after
disconnecting
communication cable to
that refrigerant line.
• Check connection of
indoor-outdoor
communication line.
• Check for trouble in indoor
power supply system.
• Check for noise from other
devices.
• Check for power failure.
• Check for failure in indoor
P.C. board.