sharp lc-60le640u

[Hornnumb2]

Working on this unit, I have check voltage to main board and are getting the 13 & 3 volts. I have check voltage to t con board and get 12v on first 2 and zero on last 2 pins. The unit does power on and has backlight but no Video or sound. I was just getting backlight but I have messed with ribbon cables on t con board and now I get some red lines on left side of screen.

[Hornnumb2]

Re: sharp lc-60le640u

Here are the boards.

[Hornnumb2]

Re: sharp lc-60le640u

Replaced t-con for no change except to clear up the red line I caused, back to backlight but nothing else. I got some more reading from top of powerboard.
1- 12.1v. PNL 12v
3- -.009 GND
5- 13.1v UR 13.2v
7- 13.1v. UR 13.2v
9- .010. GND
11- .010. GND
13- 3.31v. AC_DET
15- 5.04v. BU 5v
17- 1.15v. PWM1
19- 1.3v. Dimmer
21- 1.15v. OFL
23- .000v. PWM2

Any suggestions from that, I can check the readings on the bottom if needed. I am not sure about 17 and 23. Thanks

[freakaftr8]

Re: sharp lc-60le640u

Tcon is good. Panel is good. Sharp will fail if tcon cables are messed with while powered up. That's probably what happened. I suspect mainboard. Try heating up the mainboard with a hairdryer. probably bad bga under processor.

[Hornnumb2]

Re: sharp lc-60le640u

Thanks for the advice, ordered a main board hope that fixes it.

[Hornnumb2]

Re: sharp lc-60le640u

Well installed main board today with no change, I have a shop jimmy kit to rebuild power supply. I just know where to go from here. Thanks Michael

[budwich]

Re: sharp lc-60le640u

if you disconnect the tcon to panel cables, one at time (with power off), result do you get?

[Hornnumb2]

Re: sharp lc-60le640u

White one side black the other and vice versa.

[nomoresonys]

Re: sharp lc-60le640u

Could try a firmware update/reapply.

[budwich]

Re: sharp lc-60le640u

White one side black the other and vice versa.

somewhat expected (white).... is the white uniform when seen on both sides?

based on the card changes that you did so far, my guess would be a problem between the tcon and panel, potentially a smd component on the panel boards.

tracing the voltages from / at the tcon (labelled) and following those to the edge board might help.

[Hornnumb2]

Re: sharp lc-60le640u

Hard to get a good pic of a white screen, but the look pretty close to same to me.

[Hornnumb2]

Re: sharp lc-60le640u

I don’t know why it flipped one pic.

[budwich]

Re: sharp lc-60le640u

no problem... yes indeed they look ok. This appears to show that the panel itself is not a direct problem. However, some how the panel is not being driven.... either no signal or some operating voltage is not getting to the panel. Check the voltages on the tcon.

[Hornnumb2]

Re: sharp lc-60le640u

Voltage going into t-con or out? I did measure the 4pin PL line and get 12v on first 2 and nothing on the other 2.

[nomoresonys]

Re: sharp lc-60le640u

See if you have voltage on each side of tcon fuse, negative meter lead on a ground.

[Hornnumb2]

Re: sharp lc-60le640u

Could try a firmware update/reapply.

Not sure I can even do that with no screen display at all. I wouldn't think that would help considering the original board and replacement are doing the same thing.

[budwich]

Re: sharp lc-60le640u

Voltage going into t-con or out? I did measure the 4pin PL line and get 12v on first 2 and nothing on the other 2.

there should be a "multitude" of voltages labelled throughout the tcon... those are the ones that you need to measure / post.

alas, you picture doesn't show any TPs unlike others... maybe the other side?

[Hornnumb2]

Re: sharp lc-60le640u

Tp’s?

[nomoresonys]

Re: sharp lc-60le640u

Not sure I can even do that with no screen display at all. I wouldn't think that would help considering the original board and replacement are doing the same thing.

Well ok then supertech, if you can't you can't.

[Hornnumb2]

Re: sharp lc-60le640u

Well ok then supertech, if you can't you can't.

I wasn't trying to be a smartass, I just didn't understand how I would be able to do an update without any screen display.