LG / GOLDSTAR 42PX4R
Service Manual

TROUBLE SHOOTING GUIDE
1. Power Board
1-1. The whole flowchart which it follows in voltage output state

Start check

Doesn't the screen whole come out?

Yes

Is it identical with Power Off condition? Yes

No

Is the Interface signal operated?

Yes 2. Check the Interface signal condition.

No

1. Check the Power Off condition.

Doesn't the low pressure output come out?

Yes

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

No

Doesn't the 5V Monitor signal come out? Yes 4. Check the 5V Monitor signal circuit.

No

Doesn't the VSC signal RL-ON come out? Yes 5. Check the VSC RL-ON signal. No

No

3. Check the St-by 5V signal circuit.

Doesn't the high tension output come out?

Yes

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

No

Doesn't the Vs, Va voltage output come out? Yes 8. Check the Vs, Va voltage output circuit.

Doesn't the VSC low pressure output come out? Yes 6. Check the VSC low pressure output

No

7. Check the VSC Vs-ON signal

Does high tension output voltage Drop occur? No

Yes

When the Y, Z B/D Module input connector is remove, does Power Board hightension output voltage Drop occur? Yes 9. Check the Power Board Output high tension circuit

When the Y B/D Module No input connector is removed, does output voltage drop occur? Yes 10. Check the Z B/D Module output circuit No

When the Z B/D Module input connector is removed, does output voltage Drop occurs? Yes 11. Check the Y B/D Module output circuit

Manufacture enterprise meaning of a passage

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