LG Electronics 37LC2R, 42LC2R service manual Troubleshooting, No power

TROUBLESHOOTING

1. No power

Start check

No

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Doesn’t the

screen whole come out?

No

Doesn’t the

low pressure output

come out?

No

Doesn’t the

high tension output

come out?

	It is identical
	with power off
Yes
	condition?
		Yes

1.Check the Power off condition

	Doesn’t the
	St-by 5V signal
Yes
	come out?
		Yes

3.Check the St_by 5V signal circuit

	Doesn’t the
	VSC signal Vs-ON
Yes
	come out?
		Yes

	Is the Interface
	signal operated?
No
		No

2.Check the Interface signal condition

	Doesn’t the
	5V monitor signal
No
	come out?
		Yes

4.Check the 5V Monitor signal circuit

	Doesn’t the
	Vs,Va voltage output
No
	come out?
		Yes

	Doesn’t the			Doesn’t the VSC
	VSC signal RL_ON
				Low pressure output
No			No
	come out?
				come out?
		Yes			Yes
	5. Check the VSC RL_ON			6. Check the VSC low
	signal			pressure output

No

High tension

output Voltage drop it

occurs?

No

Manufacture enterprise meaning of a passage

	7. Check the VSC Vs_ON			8. Check the Vs, Va voltage
	signal			output circuit
	When remove			When remove			When remove
	the Y,Z B/D Module			the Y B/D Module			the Z B/D Module
	Input connector, Power			Input connector, output			Input connector, output
Yes			No			No
	Board high tension output
				voltage drop			voltage drop
	voltage drop it
				is occurs?			is occurs?
	occurs?
		Yes			Yes			Yes
	9. Check the power board			10. Check the Z B/D Module			11. Check the Y B/D Module
	output high tension circuit			output circuit			output circuit