LG 42PQ6000 plasma

[fascia-man]

Hi to all

I have a LG 42PQ6000 seems to be stuck in standby
after plugging in to the wall the only thing you can get is red led when you turn the button I/O on or off, the first few times i tried this i did get relays clicking but now nothing just red led on or off
I have checked cables and connections plus fuses on boards all seem ok

any help appreciated ?

[tom66]

Re: LG 42PQ6000 plasma

Can you supply pictures of the boards and parts inside the set?

[fascia-man]

Re: LG 42PQ6000 plasma

Hi Tom

hope these help










board numbers are

EAY59544701 power
EAX57622801 control
EAX57566202 av
EAX57633801 zsus
EAX57633701 ysus

justin

[tom66]

Re: LG 42PQ6000 plasma

OK, have you checked that fuse in the middle of the power supply? Between the 2nd and 3rd heatsinks (from the bottom of this image: https://www.badcaps.net/forum/attach...3&d=1411502216)

[fascia-man]

Re: LG 42PQ6000 plasma

just rechecked the said fuses 1 white one and 2 with black stripe all check out fine

[tom66]

Re: LG 42PQ6000 plasma

OK, using your meter, check for the 5V and other voltages on the connector going to the main board (AV board.) If possible use the legend to indicate what each voltage you tested is, for example:

AC DET - 5.0V
STBY5V - 5.2V
RL_ON - 0V

...

[fascia-man]

Re: LG 42PQ6000 plasma

Ok tom here we go

1st test red led on AV board connected

1 17v 0.00 2 17v 0.00
3 GND 0.00 4 GND 0.00
5 12v 0.01 6 12v 0.01
7 GND 0.00 8 GND 0.00
9 5v 0.06 10 5v 0.06
11 5v 0.06 12 STBY 5v 5.15
13 GND 0.00 14 GND 0.00
15 NC 0.00 16 GND 0.00
17 AC-DET 5.15 18 5v-DET 0.01
19 V5-ON 0.00 20 RL-ON 0.00
21 AUTO-GND 0.00 22 M5v-ON 0.13
23 KEY-ON 0.01 24 STBY5v 5.15

2nd test AV board disconnected (relays click twice, tcon board green led starts flashing)

1 17v 17.17 2 17v 17.17
3 GND 0.00 4 GND 0.00
5 12v 12.14 6 12v 12.14
7 GND 0.00 8 GND 0.00
9 5v 5.15 10 5v 5.15
11 5v 5.15 12 STBY5v 5.15
13 GND 0.00 14 GND 0.00
15 NC 0.00 16 GND 0.00
17 AC-DET 5.14 18 5v-DET 5.13
19 V5-ON 0.00 20 RL-ON 0.00
21 AUTO-ON 4.22 22 M5v-ON 0.00
23 KEY-ON 4.68 24 STBY5v 5.14

see what you think ?
justin

[tom66]

Re: LG 42PQ6000 plasma

Hmm, looks like an AV board fault as it's not turning on the supplies - need to rule that out.
Would you happen to have a pair of 100 to 470 ohm odd resistors? Through hole style?

[fascia-man]

Re: LG 42PQ6000 plasma

i dont have any to hand
but i can pick up some of these "Metal Film 0.6W 220 Ohm Resistor" tomorrow
any good ?
whats the plan?

[tom66]

Re: LG 42PQ6000 plasma

Yes, those will work. The plan is to jumper the power supply and turn it on. Then you can test if everything else works by engaging the self test on the panel. This will show if the main board is the fault.

[fascia-man]

Re: LG 42PQ6000 plasma

ok i have the resistors

could you help me with the self test pls

ps i dont have the remote

[tom66]

Re: LG 42PQ6000 plasma

Won't need a remote for this test, not right now at least.

Unplug TV power cable before starting.
Disconnect power board->main board connector, on the main board end.
Between V5-ON (probably VS-ON) and STBY5V connect a resistor.
Between RL-ON and STBY5V connect a resistor.
Between M5V-ON and STBY5V connect a resistor.

Now, when you plug the TV in you should get some clicks and then the Vs and Va supplies should come up to approx 200V & 60V each - do they?

[fascia-man]

Re: LG 42PQ6000 plasma

Hi yes just done it
yes it worked as you said
clicked and Vs and Va come up at 197v and 60.5v

[tom66]

Re: LG 42PQ6000 plasma

OK. Look at the screen closely, do you see a slight glow from it?

[fascia-man]

Re: LG 42PQ6000 plasma

yes

[tom66]

Re: LG 42PQ6000 plasma

Ok, can you post a closer photo of the control board, I need to be able to see the writing better.

[fascia-man]

Re: LG 42PQ6000 plasma

control board

[tom66]

Re: LG 42PQ6000 plasma

OK, just above and to the right of the "LGE PDP" writing there are two holes marked EXT AUTO GEN

Take a piece of wire and jumper these together by hooking it through both holes.

Unplug the top most connector (should go to the main board)

Plug in the TV, do you see test patterns?

[fascia-man]

Re: LG 42PQ6000 plasma

hey Tom
yes done that
its scrolling through the test patterns nicely

[tom66]

Re: LG 42PQ6000 plasma

Good, that means you will have to replace the main A/V board, this is the board with the HDMI ports on it.