Toshiba MMD-UP0721HFP Series Service Manual page 76

Check code
Main Outdoor 7-segment display
remote
Check
Sub-code
controller
code
Detected
outdoor unit No.
E28 E28
P.C.board
Compressor Fan Motor
1 2 1
01 O
02 O
03 O O
08 O
09 O O
0A O O
0B O O O
10
11 O
12 O
13 O O
18
E31 E31
19 O
1A O
1B O O
Circle (O):
Trouble
P.C. board
80
F01 — —
F02 — —
F03 — —
F04 F04 —
Location
Description
of
detection
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
Indoor unit Indoor TCJ
sensor trouble
Indoor unit Indoor TC2
sensor trouble
Indoor unit Indoor TC1
sensor trouble
I/F TD1 sensor
trouble
Check code detection
System status
condition(s)
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.
Stop of Sensor resistance is infinity
corresponding or zero (open/short circuit).
unit
Stop of Sensor resistance is infinity
corresponding or zero (open/short circuit).
unit
Stop of Sensor resistance is infinity
corresponding or zero (open/short circuit).
unit
All stop Sensor resistance is infinity
or zero (open/short circuit).
- 76 -
Check items (locations)
• Check check code
displayed on outdoor
follower unit.
<Convenient functions>
If SW04 is pressed 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
pressed simultaneously, the
fans of normal outdoor units
come on.
To stop the fan or fans,
press 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
• Check connection of TCJ
sensor connector and
wiring.
• Check resistance
characteristics of TCJ
sensor.
• Check for failure in indoor
P.C. board.
• Check connection of TC2
sensor connector and
wiring.
• Check resistance
characteristics of TC2
sensor.
• Check for failure in indoor
P.C. board.
• Check connection of TC1
sensor connector and
wiring.
• Check resistance
characteristics of TC1
sensor.
• Check for failure in indoor
P.C. board.
• Check connection of TD1
sensor connector.
• Check resistance
characteristics of TD1
sensor.
• Check for failure in outdoor
P.C. board (I/F).