LG PDP60R1 Plasma No Picture

[bawayce]

Things started to to go south about 6 months ago where the TV would need to be turned on and off a number of time before the display would initialize. At first it was just one or two times at week. At the end it we were turning it on and off for 20 minutes before getting the display. Sound and all other functions seem to work fine just the faulty display.

I have taken the back off and checked voltages on the PSU and they all check out. No bad caps or other physical damage that I can see.

I looked on line for T-shooting manuals or schematics but came up empty. Anyone have any ideas as to how I can narrow this one down?

Pics of the board numbers and back of the TV

[capkid]

Re: LG PDP60R1 Plasma No Picture

Have you checked sustain voltages? LGs usually have VSC and -Vy test points on the YSus, and they have VZB test points on the ZSus - can't see the panel label in your pics. You could also try pointing a hairdryer at various areas on either of those boards to see if a picture displays.

These appear to use the same parts: http://www.toms-service-manuals.com/...&Search=Submit

[bawayce]

Re: LG PDP60R1 Plasma No Picture

Capkid,

Thanks for your prompt and very helpful reply. These are indeed my boards and I was able to gather voltages. The YSus board Tested good with 180 and 150 Volts; however, the ZSus board ZBias tested at 15V when it should have been 105. If I run the meter on the ZBias and turn the unit on I do initial get 70V on the digital meter but then it shoots back to 15V. I would guess I would see an initial 100V if I had an analog meter.

Oh I ran a hair dryer on the ZSus board for 5 minutes but nothing changed with regards to the voltage or the display.

Any next steps?

[tom66]

Re: LG PDP60R1 Plasma No Picture

Perhaps worth running a panel self test on this to see if the main board is bad... Do you recall if the screen had the "priming glow" when faulty? (Slight glow to the black level that nearly all displays have.)

[bawayce]

Re: LG PDP60R1 Plasma No Picture

No glow. Jet black unless the display works.

[capkid]

Re: LG PDP60R1 Plasma No Picture

So, the test that Tom mentioned is also referenced on the block diagram:

(1) Disconnect LVDS cable that goes from the logic control board to the main board.
(2) Apply a jumper across the auto gen points on the logic control boards (paper clip is an OK jumper).
(3) Plug in and turn on the TV.

[bawayce]

Re: LG PDP60R1 Plasma No Picture

No love. Just the same relay clicks and no picture.

[capkid]

Re: LG PDP60R1 Plasma No Picture

It's sounding like you're down to the control board or the ZSus being the culprit. The block diagram mentions another control board test:

"To Test Control board:
Disconnect all connectors except the SMPS. When set turned on, observe Control board LED. If it's on, most likely Control board is OK.
If M5V is not present on P2 pins 1~4, jump STBY 5V from SMPS P813 Pin 13."

[bawayce]

Re: LG PDP60R1 Plasma No Picture

No LED. I actually had to look up on the diagram as I have never seen any lit led from the control board. Oh IC1 gets hot with just power attached. Prob about 130F.

Guessing this is not a component level replacement?

[bawayce]

Re: LG PDP60R1 Plasma No Picture

Green Choice OK or is there a better vendor?

https://www.encompassparts.com/item/..._Control_Board

[tom66]

Re: LG PDP60R1 Plasma No Picture

IC1, is that the large chip on the control board? Sounds bad to me.

[capkid]

Re: LG PDP60R1 Plasma No Picture

It looks like ShopJimmy is out of stock. Hmm, either they don't stock many of these or this is a common failure. Try tristatemodule.com - very reputable.

Edit: It looks like they're out, also.

[bawayce]

Re: LG PDP60R1 Plasma No Picture

Controller board is in and everything is working well.

Thanks for all your help assisting me with this issue.

Ken...

[capkid]

Re: LG PDP60R1 Plasma No Picture

Excellent. Great to hear.