Black line fault on Hyundai HPT4240 FIXED

[dave_rodger]

Hi

Thought I'd put this on here as it may well help some people.

I have a Hyundai HPT4240 screen. It had what appears to be a very common fault where the screen had a 1" black line down the middle of the screen.

After some digging around the Internet I found a site where one of the threads mentioned that this type of fault looked like a part of the screen not getting driven.

This gave me a clue where to look and after a few hours I have found the problem and the screen is now working fine. Its been on for the last 5 hours with no problem where as before the line was there every time I turned the screen on.

The actual fault I found:

Inside the screen at the bottom there is a driver board that goes behind the input board. This board has connectors on the bottom of it that go to the ribbon cables from the bottom of the screen. Half way along the ribbon cable there is a metal plate and on the back of this plate there are some surface mount components solderd onto the ribbon cables.

In total there are 6 of these cables. It appears each one controls a portion of the screen where it connects to the plasma screen. So I looked at the one just to the left of the middle. Where the components were soldered in one of the surface mount resistors had developed a dry joint. So with some carefull soldering I re-did all theresistors and capacitors (there are 4 of each per ribbon). Now the fault is no longer there. No need for a new screen or repair man + parts.

Total cost was about 8 hours to find the problem and 5 minutes with the soldering iron.

To get to these connectors means removing alot of parts from the screen so it takes a while but worth it. I have the unit soak testing now but will be putting it back together fully tomorrow. I can take pics of the problem and how to resolve it if anyone is interested.

Cheers
Dave

That's a coincidence, mine has developed the same fault just 40 minutes ago and I thought I'd do a search on AV Forums for a solution. When it first appeared I moved a few wires (about as technical as I get) and it went. Next time, moved some wires and it went again, though it took alot of wire moving By the third time of wire moving I'd realized there was something wrong with the TV and I could hear the 'Oooh, it'll cost you' already.

If you have any pics that would be great, and well done for getting to the bottom of the problem (assuming the black line hasn't come back, no update yet)

[freeman]

Mine had the turning off & refusing to turn back on problem .Luckily I took out the extended warranty (failed at just over two years) & it's now Comets problem Mine failed on new years eve,phoned Comet next day ,is it wall mounted ? answer yes ,ok engineer coming friday.
Friday came,engineer turned up ,it's wall mounted noted engineer ,yes I said it was when I phoned up the other day.There's two of us we can lift it down says I ,no health & safety won't let me ask you to help lift it down says engineer ,& Comet won't send two engineers on a first vist.
Due to there being two differnt board sets for this tv we will have to collect & take to our depot to look at .Comet collect next tuesday & tell me tv will be returned on the 23rd (a fortnight later).
23rd arrives not a peep from Comet ,so I wait for tv to be returned ,decide to phone Comet in the afternoon to see where tv is ,& they claim 23rd was not a confermed date & they are waiting for parts still (no idea how long they'll be ).
So I was all set to to Currys & pick up another tv(they had some for store collection) ,when I get a phone call from Comet service deptment ,they can't get the parts to fix the tv
But then give me a code to take to my local store for an exchange ,what money is the exchange for I ask as this tv hasn't been sold for a while .How much did you pay for it the service deptment asked ,£1300 I replyed ,that's how much you can have then was the answer
Now waiting for my new Pinoneer 4270xd to be delivered

[dave_rodger]

Hi

No problem has not returned. Given it was there all the time at the end and its been on for a long time now without issue I'd say the problem is fixed.

I did take some pics but they are not too good. Will post them up later tonight.

Dave

[dave_rodger]

This is a pic of one of the riboon cables. There are 6 on my TV that run along the bottom of the screen, Each one controlls the area above it so you cna guess well which one may be at fault. this is one of the end ones as the TV was back together when the pics were taken.

If you take the clips out from the board for the cable then take the metal plate off it will litf up and reveal some parts soldered onto the back of the plate and cable. I re-soldered all the parts (4 resistors and 4 caps) on the cables in the middle of the screen.

To get to the cables in the middle of the screen meant I had to remove the input board as the cables were under the ports on the bottom of the screen. This is what took the time.

Again appologies for the poor quality, couldnt find the camera so had to use my phone which is none too good.

hope it helps

Dave

[camorra]

nice post with informative help to owners of such a model!!

pics are ok

....and to repairmen too

thanks

Sorry for the last reply, black line hasn'r been around since so forgot about it - until yesterday when it came back. Thanks for the pics and advice, much appreciatted, and I've just spotted another poster with the same problem so I'll give him this link

[BIG-D]

good post dave r, (the soldering on the cable resisters and caps must have been difficult.) Could u explain in a bit more detail on the soldering if possible THANKS !!

i have had the same problem, with the same model, i looked for any dry joints but did not find any. (i have two back lines in center of screen).

but i did notice a burn on the underside of my input board, looks like it come from the speaker inputs. think i have a bigger problem.

but and help would be good !

http://www.avforums.com/forums/image...ies/please.gif

[dave_rodger]

Hi

Its not too hard to do but you do need a good soldering iron with a fine tip (B&Q etc do them for about £10). All I did was go over each joint and touch it up with a fresh bit of solder. If you do one side of each component, and then the other side so you dont get the componenets too hot.

I will say that as for the dry joints you cant see them as the components are surface mounted but for the sake of just re touching the joints which takes little time then its got to be worth a try.

Since doing mine I've had no problems at all with the TV.

[BIG-D]

Originally Posted by dave_rodger

Hi

Its not too hard to do but you do need a good soldering iron with a fine tip (B&Q etc do them for about £10). All I did was go over each joint and touch it up with a fresh bit of solder. If you do one side of each component, and then the other side so you dont get the componenets too hot.

I will say that as for the dry joints you cant see them as the components are surface mounted but for the sake of just re touching the joints which takes little time then its got to be worth a try.

Since doing mine I've had no problems at all with the TV.

THANKS FOR POST DAVE-R

I'll give it a go in the week when i've got myself a good soldering iron, I'll post results. Been searching for a long time for this help. Nice One...

[ahus98]

Hi, i've had this problem with the black line on the screen just left of the middle. I've opened the screen and attempted to follow instructions of what could possibly be the fault in soldering. I beleive i found the part, but see from the pictures.....

I need to get myself a small soldering iron & figure out whether to attempt just retouching the little guys called C1 - C4 / R1 - R4 or both.

First we have the input board, then i removed it in the picture below, which shows 7 ribbon cables connected to the screen (well i think their all connected to the screen). I removed one of the ribbon cables in the picture by lifting the brown plastic clip upwards.

Then finally this is one of the ribbon cables...

UPDATE: PLEASE NOTE ONLY SOLDER THE LARGE ONES WITH 100 WRITTEN ON THEM, IT DID THE JOB FOR ME.

I Wonder will this really solve the problem, has anyone else had this problem & fixed it ??

I've not yet done anything to it, but its a cool tv, would be nice if i could fix it, the line on my screen appears, disappears whenever it feels like it.

thanks (especially to dave for the instructions on wat to look for, hope this can be fixed)

[BIG-D]

SORRY I am late with post of results of DAVE-R instructions for the D.I.Y fix it for the hyundai plasma.

It did work, could'nt be happier big thanks dave -r.



All it took was a touch up of dry soldering on all EIGHT components. ( Carefully)
(follow dave-r instructions, solder each side of a component to keep from over heating)
plasma has been on for over 8 hours, NO problems.

thanks dave-r

[ahus98]

Thanks for the report BIG-D, i guess i'll be the next to try it, the components are so tiny though i hope i dont mess it up.

Ah so u did do all 8 of those components, the C/R 1-4's. How did u manage to add solder to the very tiny ones, how much time did it take to complete.

Take the tv apart was quite simple, although we cant see the fault, is it correct to assume its the cable nearest to the line on the screen and is there anything else which could cause such a problem, that is if anyone knows.

I'll b attempting the soldering in the next couple of days.

thanks for the feedback.

[BIG-D]

Did'nt need to add solder, just carefully dry soldered the components, (heating up the existing solder with a very narrow solder iron). Always allowing cooling time.

[BIG-D]

Originally Posted by BIG-D

Did'nt need to add solder, just carefully dry soldered the components, (heating up the existing solder with a very narrow solder iron). Always allowing cooling time.

Soldering took about 5 mins including cooling time.