Troubleshooting For Indoor Unit - Toshiba RAS-18NKHD-E5 Service Manual

9-6. Troubleshooting for Indoor unit

9-6-1. Power can not be turned on. (The unit does not operate at all.)
<Primar check>
(1) Is the supply voltage normal?
(2) Is the connection to the AC output OK?
(3) Is the fuse (F01) blown?
Is fuse (F01)
control board
Is voltage (DC
12V or 5V)
NO
indicated on
rear of indoor
control board
Is DC 310 -
NO
340V across
C63?
YES
Turn off breaker
Are DC 12V, NO
once and turn it
across C66?
on again after
removing motor.
YES
Turn off power
supply once, and 5
second later, turn it
on again.
NO
Is OPERATION
lamp blinking?
YES
Is it possible to
turn on power
supply by
pressing
[START/STOP]
button on remote
control?
YES
Parts (R21,
R22, SG01,
YES
of indoor C01, DB01,
C02,
blown?
M01 and IC04)
are defective.
NO
YES
normal?
Are DC 12V,
across C66?
Does
transmission
mark on
NO remote
NO
control flash
normally, and
is its signal
transmitted
properly?
YES
Does the fan
motor
connector
between 1
and 2 short-
circuit?
Microcomputer is
defective.
NO
M01 is
YES
– 55−
FILE NO. SVM-06005
Operation
Check item
Conceivable principle
cause
Measure
Item by symptoms
Remote control is
defective.
Refer to 9-9
" Troubleshooting for
Remote Control."
Unit operates
normally.
YES
NO
Replace main P.C.
board.
Replace motor.