BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

[oddbodd]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

Hello guys great reading. I have a jvc lt24dg42j which is dead and uses the same power board (which also is dead), I have ordered the caps but was wondering about the epoxy paste, I take its the same stuff as used on processor heatsinks, Can you explain how this would be used please to a newby who likes experimenting.

I only had some of the thermal paste for CPU heatsinks, so used that.

It has to be better than nothing.

[oddbodd]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

Since the repair, I've tried to use the TV as a PC monitor [VGA connection], but the picture flashes rapidly. It was working OK in TV mode. I've tried different refresh rates, but nothing stops the flashing.

I shall test with an HDMI cable when I have one, but now it's started flashing in TV mode as well. It sometimes stops after a short while with a decent picture, but changing some of the TV settings will start it off again. The rate of the flashing depends on which setting is been changed.

Could it be anything to do with the repair? Should I not have used UF5408 diodes?

[Alastair E]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

Can you see if its the backlight that's doing the flashing--or the actual image on the screen?

[oddbodd]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

What's the easiest way of checking the backlight?

[Alastair E]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

Without the back on the set, you can often see through cracks/gaps on the metal-work or screw-holes the backlight working.

[oddbodd]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

OK, but what what am I looking for?

I have a picture on the screen, but it flashes/flickers rapidly.

[Alastair E]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

Well--Is it caused by the backlight flickering....?

[oddbodd]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

Without checking, I would say yes, probably, but it'll have to wait for now...

[wil71]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

Got the diodes today and installed them. Tv is alive again, just want to say thanks for the valuable info on this thread. Ordered Halnziye HY910 heatsink adheseve non conductive from ebay, only £2.30 with free delivery, link below. anyone used this? any good?

http://www.ebay.co.uk/itm/2616056625...%3AMEBIDX%3AIT

[tom66]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

I use that stuff, works great.

[oddbodd]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

Without the back on the set, you can often see through cracks/gaps on the metal-work or screw-holes the backlight working.

There's a small hole in each of the very top corners. I can see a light flashing, so presumably that's the backlight?

[tom66]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

There's a small hole in each of the very top corners. I can see a light flashing, so presumably that's the backlight?

Yes. That pulsates with the picture right?

[oddbodd]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

Yes. When the picture does stabilise, so does the light in the corner.

[oddbodd]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

Does this mean that the voltage is fluctuating? Should I look at those diodes again?

[tom66]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

I would check if the outputs from the power supply are stable.

[oddbodd]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

Well, there's a small fluctuation of about 0.5v on some of the pins.

[tom66]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

0.5V can be significant, on which rail do you measure this?

[oddbodd]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

Measurements taken from the connection pins on the inverter board [17CON08-2 - V1] ...

Whilst flickering...
1: 0.00 to 0.01
2: 0.00 to 0.01
3: 1.56 to 1.57
4: 2.75 to 2.78
5: 26.0 to 26.3
6: 26.0 to 26.3

Stable picture...
1: 0.00 to 0.01
2: 0.00 to 0.01
3: 0.23
4: 2.75 to 2.78
5: 25.5 to 25.7
6: 25.5 to 25.7

[oddbodd]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

Any clues as to the differences?

[budm]

Re: BUSH LED2497ODVDFHD, 17PW80 V2, Dead!

# 3 does not look right, 1.56V when flickering, and 0.23V when stable.
Do you know if # 3 is the dimming control line and #4 is the BL_ON line?