Toshiba MMY-MUP0721HT9P-UL Service Manual page 182

Check code
Outdoor 7-segment display
Controller
Check
Sub-code
code
E23 E23 —
E25 E25 —
Address of
outdoor unit
from which
signal is not
received
normally
E26 E26
The Detected
check outdoor unit No.
code
which
occurred
follower
outdoor
unit is
displayed
E28
P.C.board
Compressor Fan Motor
1 2 1
01 O
02 O
O
03 O
08 O
09 O O
0A O O
0B O O O
10
11 O
12 O
13 O O
18 O
E31 E31
19 O O
1A O O
1B O O O
Circle (O):
Trouble
P.C. board
80
Location
Description
of
detection
I/F Outdooroutdoor
communication
transmission
trouble
I/F Duplicated
follower outdoor
address
I/F Signal lack of
outdoor unit
I/F Outdoor
follower unit
trouble
I/F P.C. board
communication
2
trouble
O
O
O
O
O
O
O
O
Communication
trouble between
MCU and Sub
MCU
Check code detection
System status
condition(s)
All stop Signal cannot be transmitted
to other outdoor units for at
least 30 seconds
continuously.
All stop There is duplication in
outdoor addresses set
manually.
All stop Outdoor unit initially
communicating normally
fails to return signal for
specified length of time.
All stop Outdoor header unit
receives trouble code from
outdoor follower unit.
All stop Communication is disrupted
between P.C. board in
inverter box.
All stop Communication between
MCU and Sub MCU
stopped.
- 182 -
Check items (locations)
• Check power supply to
outdoor units. (Is power
turned on?)
• Check connection of tie
cables between outdoor
units for bad contact or
broken wire.
• Check communication
connectors on outdoor
P.C. boards.
• Check for failure in outdoor
P.C. board (I/F).
• Check termination
resistance setting for
communication between
outdoor units.
Note:
Do not set outdoor
addresses manually.
• Backup setting is being
used for outdoor units.
• Check power supply to
outdoor unit. (Is power
turned on?)
• Check connection of tie
cables between outdoor
units for bad contact or
broken wire.
• Check communication
connectors on outdoor
P.C. boards.
• Check for failure in outdoor
P.C. board (I/F).
• Check check code
displayed on outdoor
follower unit.
<Convenient functions>
If SW04 is pushed and held
for at least 1 second while
[E28] is displayed on the 7-
segment display of outdoor
header unit, the fan of the
outdoor unit that has been
shut down due to an trouble
comes on.
If SW04 and SW05 are
pushed simultaneously, the
fans of normal outdoor units
come on.
To stop the fan or fans, push
SW05 on its own.
• Check wiring and
connectors involved in
communication between
P.C. board I/F P.C. board for
bad contact or broken wire.
• Check for failure in outdoor
P.C. board (I/F, comp. P.C.
board or Fan P.C. board).
• Check for external noise.
• Operation of power supply
reset (OFF for 60 seconds
or more)
• Outdoor I/F PC board
trouble check