Samsung UD18B1C2, UD26B1C2, AD18B1C09 When the power voltage is not available, Indoor unit on when

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

					Apply the power
	YES	Is the operation lamp of
				YES
No trouble		indoor unit on when the			Is the operation lamp flickering with the
(normal)		operation /stop button of			sound of “ting”?
		remote controller is
		pressed?				NO
			NO

Check of remote

controller

Normal

Is the communication

NO

signal of remote

controller surely sent

and received ?

	YES
YES	Is there no problem
	between the connector of
	Ass’y display PCB and the
	receiving module?
	NO
	Replace of
	Ass'y display PCB

NO

Is the outdoor power connected normally?

YES

YES

Is the fuse (F701, 250V, 3.15A) of PCB open?

NO
Is the voltage at Socondary side of transformer	NO
of PCB (TN71)? (AC15V~AC25V)
YES

Check of the installation

method and electrical circuit

Replace the fuse (250V, 3.15 A)

Transformer is out of

order - replace

Is the output voltage of voltage regulator

IC (KA 7812) DC 10V and 12V?

YES

Is the output voltage of electrostatic voltage

regulator IC (KA 7805) DC 4.5 V - 5.5 V?

YES

NO

NO

Repair and replace the power source rectifying diode (D101- D105) and KA7812.

KA7805 is out of order - replace

Replace the main PCB of indoor unit

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