Caution At Servicing - Toshiba RAS-M10UKV-E3 Service Manual

10-4-2. Caution at Servicing

(1) After servicing, push the START/STOP button to return to the normal mode.
(2) After servicing by the check code, turn off breaker of the power supply, and turn on breaker of the power
supply again so that memory in the microcomputer returns the initial status. However, the check codes are
not deleted even if the power supply is turned off because they are stored in the fixed memory.
Block distinction
Check
Block
code
Indoor P.C.
board etc.
Not
displayed
Connecting
cable and
serial signal
Operation of diagnosis function
Check
Cause of operation
code
Short-circuit or disconnec-
tion of the room tempera-
ture sensor (TA sensor).
Coming-off,
disconnection,
short-circuit, or migration
of heat exchanger sensor
(TC sensor)
Lock of indoor fan or
trouble on the indoor fan
circuit
Trouble on other indoor
P.C. boards
Return serial signal is not
sent to indoor side from
operation started.
(1) Defective wiring of
connecting cable
(2) Operation of
compressor thermo.
Gas shortage
Gas leak
Operation command
signal is not sent to
outdoor side.
Table 10-4-1
Air
conditioner
Condition
status
Operation Displayed when
continues. error is detected.
Operation Displayed when
continues.
error is detected.
All off Displayed when
error is detected.
Operation
Displayed when
continues. error is detected.
Operation Flashes when
continues. trouble is detected
on Return serial
signal, and normal
status when signal
is reset.
Operation Flashes when
continues. trouble is detected
on Operation
command signal,
and normal status
when signal is
reset.
– 83 –
Judgment and action
1. Check the room temp. sensor.
2. When the room temp. sensor is
normal, check P.C. board.
1. Check heat exchanger sensor.
2. When heat exchanger sensor is
normal, check P.C. board.
1. Check P.C. board.
2. When P.C. board is normal, check
the motor.
Replace P.C. board.
1. When the outdoor unit never
operate:
(1) Check connecting cable, and
correct if defective wiring.
(2) Check 25A ( or 30A) fuse (F01)
of outdoor main P.C. board.
(3) Check 3.15A fuse (F04) of
outdoor main P.C. board.
2. To display [Other] block during
operation, check compressor
thermo. operation and supply gas
(check gas leak also).
3. Unit operates normally during
check.
If Return serial signal does not
stop between indoor terminal
board 2 and 3, replace inverter P .C.
board.
If signal stops between indoor
terminal board 2 and 3, replace
indoor P.C. board.
If Operation command signal does not
stop between indoor terminal board 2
and 3, replace inverter P.C. board.
If signal stops between indoor
terminal board 2 and 3, replace indoor
P.C. board.