Toshiba RAS-18SKV-E Service Manual page 70

11-4-2. Caution at Servicing
1. After servicing, press 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.
3. After servicing, press [CLR] button under check mode status and then send the check code "7F" to the
indoor unit. The error code stored in memory is cleared.
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 discon-
nection of the room
temperature sensor
(TA sensor).
Being out of place,
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 compres-
sor thermo Gas
shortage Gas leak
Table 11-4-1
Air
conditioner Remarks
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.
– 69 –
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 the motor.
2. When the motor is normal,
check P .C. board.
Replace P .C. board.
1. When the outdoor unit never
operate:
1) Check connecting cable, and
correct if defective wiring.
2) Check 25A fuse of inverter
P .C. board.
3) Check 3.15A of inverter 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.