Samsung AD26B1C13 Service Manual page 13

3-3-2 When the power voltage is not available
1) Inspection items
(1) Is the power voltage is normal? (The rating voltage ±10% range)
(2) Is the power cord is correctly connected and is the contact good?
(3) Does the sound "ting" come out with the operation lamp (green) flickering when the
power is applied?
If it is not flickering, do inspect and repair in accordance with the following inspection
sequence.
2) Inspection sequence
Is the operation lamp of
YES
indoor unit on when the
No trouble
operation /stop button of
(normal)
remote controller is
Is the communication
NO
Check of remote signal of remote
controller controller surely sent
and received ?
Is there no problem
YES
between the connector of
Normal
Ass'y display PCB and the
receiving module?
Ass'y display PCB
12
YES
Is the operation lamp flickering with the
pressed?
NO
Is the outdoor power connected normally?
YES
Is the fuse (F701, 250V, 3.15A) of PCB open?
NO
Replace of
Is the voltage at Socondary side of transformer
Is the output voltage of voltage regulator
Is the output voltage of electrostatic voltage
regulator IC (KA 7805) DC 4.5 V - 5.5 V?
Replace the main PCB of indoor unit
Apply the power
sound of "ting"?
NO
YES
NO
of PCB (TN71)? (AC15V~AC25V)
YES
IC (KA 7812) DC 10V and 12V?
YES
YES
NO
Check of the installation
method and electrical circuit
YES
Replace the fuse (250V, 3.15 A)
NO
Transformer is out of
order - replace
NO Repair and replace the power
source rectifying diode (D101-
D105) and KA7812.
NO
KA7805 is out of order - replace