Sharp LC-42D62U Inverter board

[budm]

Re: Sharp LC-42D62U Inverter board

Do you have the LCD panel number, there should be a sticker on the LCD panel some where, I will need to look up the spec sheet which will give us the pinout of the inverter boards and the signals,I want to see if it has an error signal pin.
It is not easy troubleshooting long distance when you do not have the set right in front of you.

[FlipTV]

Re: Sharp LC-42D62U Inverter board

Points 1 and 2 have the same readings

When the screen is on it reads 12v

When it goes black, it reads. 03

[budm]

Re: Sharp LC-42D62U Inverter board

I expect 12V just on one end of them since it is the bridge drive setup, but not at both ends. Put the meter in AC mode (it may not show anything due to the meter bandwidth) and do the same test.

[FlipTV]

Re: Sharp LC-42D62U Inverter board

The service manual lists the lcd as r1lk420d3lf21

[budm]

Re: Sharp LC-42D62U Inverter board

Sharp panel?

[FlipTV]

Re: Sharp LC-42D62U Inverter board

It is a sharp tv not sure on the panel yet.

I'll have to open the front up tomorrow after work to see.

The sm lists that part # for the lcd

[Lumberjack777]

Re: Sharp LC-42D62U Inverter board

When I looked at the picture of the "burn mark" way back in post #9.... it appears that you have a ccfl wire that is arcing at the connector. I had a connector that did that once and it ended up causing the 2 seconds to black issue. I ended up having to replace the wire connector to finally get it to stop arcing and it fixed the problem.

[FlipTV]

Re: Sharp LC-42D62U Inverter board

When you say wire connector, did you replace the tip or did you replace the wire and the tip?

Where would I find a replacement tip /connector from?

[tom66]

Re: Sharp LC-42D62U Inverter board

ChiMeiOpto panel, inverter is by CMO.

[FlipTV]

Re: Sharp LC-42D62U Inverter board

I don't see any damage to the connector though. Should I see any indications of damage on the connector?

[Lumberjack777]

Re: Sharp LC-42D62U Inverter board

I don't see any damage to the connector though. Should I see any indications of damage on the connector?

Yes you should see damage near the pink wire on the connector from the CCFL. I'm rather baffled that the board could be so damaged, but not the wire connector. There was definitely some sort of short or arcing there at some point.
If you can; start it up in a dark room and look for some sort of flash from that exact point. It'll happen very quickly and shut down the back lights if its still arcing.
In order to fix it I had a spare monitor and used the ccfl connector from that one and simply spliced and soldered the wires and plugged it in.
I might be way off. But something caused that damage in the first place. Good luck

[FlipTV]

Re: Sharp LC-42D62U Inverter board

Think I can avoid that one lamp by soldering a jumper wire on 2 points on the transformer and removing the transformer completely?

[tom66]

Re: Sharp LC-42D62U Inverter board

Probably, but it won't look good (dark bar running through screen.) You'd have to disable the error detect too.

[FlipTV]

Re: Sharp LC-42D62U Inverter board

Shoot. I'm stumped on what to do.

[Lumberjack777]

Re: Sharp LC-42D62U Inverter board

So are you using the old boards and you also seat all the lamp connectors, clean the burnt connector real well? If one of the lamp does not turn on or will not fire up, or not connected or stays conducting, it will also shutdown the inverter.

I think budm suspects the same thing that I do. It's not making a solid connection at that point where the pink wire plugs into the inverter. Once it starts arcing it can build up corrosion (for lack of a better term) (black soot) inside the connector. Also, the pink wire may not be solidly connected inside the wire connector. I'd check that area really closely and clean it out and make sure the pink wire is solidly attached inside the connector. Then use the new board, and it should, (might) (hopefully) (crossing fingers) work.
The other possibility is a bad ccfl. But check that connection really closely first.

[FlipTV]

Re: Sharp LC-42D62U Inverter board

Man you won't believe this.

I haven't touched the tv in a few days, powered on the tv and left it on for a few minutes, then powered it off.

When I turned it back on I no longer got 2 seconds to black.

I checked the white fuses 5a/160v and one side does not read 24v.

I think that arcing is definitely popping the fuse.

I think it's time to part out this tv and try to fix another display.

Thanks everyone for all your input.