Carrier 38CJR018-723 - Troubleshooting for Indoor Unit

– 58−
FILE NO. SVM-05010
9-6. Troubleshooting for Indoor Unit
9-6-1. Power can not be turned on. (The unit does not operate at all.)
<Primary check>
(1) Is the supply voltage normal?
(2) Is the connection to the AC output OK?
(3) Is the fuse (F01) blown?
Turn off power
supply once, and 5
second later, turn it
on again.
Is OPERATION
lamp blinking?
NO
YES
NO
NO
YES
YES
Is it possible to
turn on power
supply by
pressing
[START/STOP]
button on remote
control?
Does
transmission
mark on
remote
control flash
normally, and
is its signal
transmitted
properly?
Remote control is
defective.
Refer to 9-9
ÒTroubleshooting for
Remote Control.Ó
Parts (R21,
R22, SG01,
C01, DB01,
C02,
M01 and IC04)
are defective.
Is fuse (F01)
of indoor
control board
blown?
Is voltage (DC
12V or 5V)
indicated on
rear of indoor
control board
normal?
Microcomputer is
defective.
Replace main P.C.
board.
Is DC 310 -
340V across
C63?
Are DC 12V,
across C66?
Turn off breaker
once and turn it
on again after
removing motor.
Are DC 12V,
across C66?
M01 is
def
ec
tive.
Replace motor.
YES
YES
NO
NO
NO
NO
YES
YES
YES
NO
NO
YES
Does the fan
motor
connector
between 1
and 2 short-
circuit?
Unit operates
normally.
Operation
Measure
Item by symptoms
Check item
Conceivable principle
cause