Another LC-80LE632U 2-5 thread

[budwich]

Re: Another LC-80LE632U 2-5 thread

I would see if you can get into the service menu to check the error counters to see if they point at anything. Still appears to be a backlight issue... maybe "poor board work"... :-)

[budwich]

Re: Another LC-80LE632U 2-5 thread

just adding that you might have to "zero" the error counters to cause the set to operate correctly. This has to be done from the service menu or they are not reset otherwise.

[kimarcher_gy]

Re: Another LC-80LE632U 2-5 thread

I am not getting to go into the Service Menu I just get a flash of the backlight.

I left it disconnected overnight and when I switched it on today I got a view of the Menu long enough to tune all the cable channels then after that the backlight went off but if I switch the TV off then back on I just get a flash of the Menu or Channel. I made a video of this event but the file is around 190mb so I did not upload same.

I did a re-check of the voltages at connector PD without backlight and a steady Power light and got the following results in the attached jpeg file.

[kimarcher_gy]

Re: Another LC-80LE632U 2-5 thread

Please see attached Jpeg with the voltages on all pins.

[budwich]

Re: Another LC-80LE632U 2-5 thread

if I understand the readings (limited experience), the system is erroring.... but I don't see anything else. :-( maybe someone else will have an idea. might want to post pictures of some of your "board work" just in case people can spot something.

Further, from your last statement, I take this that IF you leave it unplugged overnight, that you were able to get something done (scanning of channels). IF this (menuing) can be achieved again (regularly... one day wait), then again you should try and get into the service menu and look at the error counters to see which may be pointing to an issue although it still might be backlighting related.

Still further, my understanding from reading some of the service manual of "similar sets" that there is a boot up process that turns off the "lamp error detection" so that the set will "run" without causing a lamp error related shut down.... if you use this and it still shut down, there is a significant issue.

[kimarcher_gy]

Re: Another LC-80LE632U 2-5 thread

Please see attached picture files of board work on installation of IR2E67M chip.

[kimarcher_gy]

Re: Another LC-80LE632U 2-5 thread

Please see attached picture file of TV screen just before the backlight came off .

[budwich]

Re: Another LC-80LE632U 2-5 thread

some of your pictures appear to show "foreign lines" running from one pin to another. Ensure there is no "contamination" between pins as the high voltages may "leak" thru to areas they shouldn't be.

Might be a main board problem if the "power strike" caused a weakening of a component (eg. capacitor). Might look for a replacement board somewhere.

[kimarcher_gy]

Re: Another LC-80LE632U 2-5 thread

There are some left over Fibers from a Cotton Cloth that I was cleaning the pins with.I used Isopropyl Alcohol to get off excess soldering flux .

[kimarcher_gy]

Re: Another LC-80LE632U 2-5 thread

Please see attached picture file with some data on the IR2E67U chip.

[kimarcher_gy]

Re: Another LC-80LE632U 2-5 thread

That should be IR2E67M.

[kimarcher_gy]

Re: Another LC-80LE632U 2-5 thread

Hello all, "Happy New Year".
The present state of the TV is as follows:-[1] I have installed the original Power Supply Board after replacing the Backlight Driver IC .[2] I have replaced the Main Board with the original Board after reflowing the Power supply connector soldering joints, [3] I replaced the T-CON Board with the original board and replaced the two flat ribbon cables with new ones due discolored ends and corrosion.
Presently I am getting Video and Audio and images on screen without backlight . and if I unplug the Power cord it goes back to 1S-1F Blink error.
The Back light is not coming on even if I leave the TV off overnight I came to the conclusion that the Rainy weather is making the TV Circuit Boards operate sluggish so I placed two lights behind the TV to keep the boards warm.
I am getting +127 VDC on all the pins of the LED positive wires and 1.8 VDC across the Collector and Emitter of all the Main Driver Transistors (KCY4217 or C4217 )
Please see attached voltage chart with present voltages in this condition.
The E-Bay T-CON Board that was removed was working satisfactory .
The E-Bay Main Board removed ,was not getting Video or Audio because I did not get to complete the auto tune cycle with it but I believe it's serviceable.

[budwich]

Re: Another LC-80LE632U 2-5 thread

although the voltage on the led drivers is important, it isn't necessarily the sole "thing". The system is actually relying on current and if you are exceeding the current spec (likely because of a "poor led") then it may be shutting down. The ERROR line is still high. As suggested, you should be able to "force" the backlights.

[kimarcher_gy]

Re: Another LC-80LE632U 2-5 thread

I have done some reverse engineering to draw a part of the Power Supply Schematic for P/N: RUNTKB096WJQZ. It's a work in progress but from this diagram you could do a modification to fool IC7002 about the current hopefully. The alternative is to change all the LED, s with new ones which is very expensive as recommended by a Technician on Fixya.com. I have removed the whole panel with the Back light LED's and tested them and they are all displaying with the same brilliance.

[Robottom]

Re: Another LC-80LE632U 2-5 thread

Hi folks, I am new to the forum and haven't figured out how to start a new thread or if I'm even allowed to do that yet. Anyway, I'm hoping someone can give me a little help with what I think is a similar problem to what's being discussed in this thread.

I have a Sharp LC-80LE642U that just started giving me the 1s - 1l blink code, nothing visible on the screen. I have it off the wall and back stripped off laying face down on a bed in our spare room. I am pretty familiar with electronics, but far from an expert.

I'm trying to figure out if I can force the power supply to stay on so that I can see it is powering the backlight LEDs. I saw a UTube video (https://www.youtube.com/watch?v=fBWX34wTULw) where he disconnects the cable from the main board and used jumpers and switches to simulate the inputs from the main board to fool the power board. Unfortunately I do not have the same power board and the pins he was jumping are not all available on my board. I have RUNTKB096WJQZ which does not have any pin marked PWM1. The reason I want to do this is to make sure that the power board is actually good before tearing apart the LCD panel. This is a BIG HEAVY and EXPENSIVE TV, so I'm trying very hard to test the easy repair stuff before going any further.

I guess, what I really want to ask is if there is a way to positively test each of the boards to be sure they're good before doing anything else. I'd like to start with the power board.

I did see in this thread someone recommended disconnecting the ribbon cables going from the TCon board to the panel, but I wasn't sure if that would help me test the power board and light up the LEDs.

Anyway, I have tested voltage from the power board out of pins 1, 3 and 5 on connector L1, which I believe is power + to the LED strips, and got ~130 VDC for a short period after plugging the TV in while holding Input and Vol - simultaneously. I am pretty sure that's good, but not 100% confident that means the problem is one or more of the LED strips. As, above, this is a big honking piece of equipment and I really don't want to go there if I don't have to.

Any help with board testing especially power board would be appreciated. If I have to open the panel, I'm pretty sure I can manage testing the LED strips even though that wouldn't eliminate any of the boards as part of the problem. I am assuming that if I go that far and all the LEDs light up, one of the boards must be bad, but then ... which one?

Thank all of you in advance for any help.

Best Regards,
Tom

[kimarcher_gy]

Re: Another LC-80LE632U 2-5 thread

Hello ,Robottom.
You could follow the Link to get a Service Manual for your model;- https://www.manualslib.com/manual/11...?page=5#manual

The Service Manual does not have a diagram for the Power Supply Board,however is has the same part number as the one in the Service Manual for the LC-80LE632U TV.

You could test the fifteen LED rows from the connector the information of pin out is written on the board. There are thirty LED in series in each row.

[kimarcher_gy]

Re: Another LC-80LE632U 2-5 thread

I have made a correction to the Diagram of the LED power supply where the two connectors L1 and L2 were labelled incorrect .This diagram covers only four rows of LED's out of fifteen all of which connect to different pins of the IC in a simular way .I have purchased another new Board with the same Part Number quoted in the Service Manual ..I will do a resistance test before to check for leakages of current to chassis simular to the test below.
I will be re-testing the LED's by leaving the Connector L1 plugged in and applyng 147 Volts Positive from the LED tester Red lead to pins 1 which connect to all the fifteen rows of LED anodes and testing the Cathode side with the connector L2 disconnected and selecting each of the pins that goes to the first Cathode of each row. The information is marked at the side of the connector . I would be monitoring the Current of the Positive lead of the tester for leaks to ground.

[kimarcher_gy]

Re: Another LC-80LE632U 2-5 thread

Hello members I must say to you that I have come to the realization that some or all Led Lamps loose their brilliance after a couple of years .I have been using a 13 watt 1200 Lumens LED lamp for a couple of years and it is presently about half it's original luminance .so I decided to change all the Back-lighting Leds for the 80 inch Sharp in a couple of days . I am purchasing a Power Supply Board and a complete set of LED's from a damage Screen 80 inch Sharp TV.
I tried modifying the Sharp Power Supply board to fool the IC 7201 that the LED's are drawing a lower current by reducing al the sensing resistor by a half of it's value but the 3.3 Volt regulator a very small six pin IC went defective and I cant get the number to replace same .

[kimarcher_gy]

Re: Another LC-80LE632U 2-5 thread

I am seeking some guidance for my next move .

After changing the LED, s and the Power Supply Board with ones from a cracked screen TV I got the TV to work for about three days. The next day it refused to come on so I did normal reset by pressing V+,V- and CH- and I got it to work with ¼ of the screen missing on the left side. but after a few minutes it would go to a 2-3 code . I don't want to start ripping out the left side board ribbon cables until I am certain there is no other fix for this. Please see the attached when it was working good and the present condition .My two spare T-CON boards are not working but I am getting 500 ohms from the 12 v pins to ground. I am using the T-CON Board from the cracked screen TV mention above.

The Power Supply board is an older type as listed in the Service ,Manual for the LC-80LE632U.

[budwich]

Re: Another LC-80LE632U 2-5 thread

that problem IS NOT an issue that can be solved by removing the side tabs so don't go there. you have an issue at the bottom of the set. IF you disconnect the left side (from the front) tcon to panel cables, what happens to the screen display? Check the tabs along the bottom along with the edge boards.