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Bad solder connections on the vertical ic

How can i fix a solder connection

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Re: bad solder connections on the vertical ic


Cold solder is normally fix with re-application of heat using a soldering iron. This is a fairly straight forward job and should not be that difficult. Probably what would take more time is opening the back cover and exposing the solder side of the PCB. Most TV PCBs are slide in/out (it may held in place by screws or retaining clips or side locks. Additionally, some of the wires/connectors may restrict movement and therefore must be disconnected temporarily).

Good luck and kind regards.

Posted on Dec 08, 2007

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My tv all of a sudden has horizontal lines across the picture.

You have bad grounds on your vertical IC. And you have a bad capacitor or two. I don't recall the actual location of the vertical IC location. I would say it may be U4501 location. Resolder the seven pins of this IC. Now check capacitor locations C4505 which is a 35 volt 220 Mf value, and C4506 which is a 63 volt 330 Mf value.Replace these caps as necessary. Then check the solder grounds at the power supply chip U4101, this chip is a switch mode regulator and may become detached from the board. Resolder these 11 pins and be careful not to short the pins with too much solder. Please note the two pins on the right (separated by a missing pin) are soldered together, this is OK. Now for the biggest challenge. You must pull the bottom shield off the tuner (has the RF connection). Yes, this area can produce the horizontal lines you speak of. When removed, you will see about 15 bad solder connections. This area will require great skill to resolder. The solder on the perimeter of this tuner is very difficult to work with, and you do not want to burn off any traces connecting to out side feeds. You could destroy this board. Now inside the tuner area there will be 5 pins or grounds that will need resoldered. Be careful here and not to burn off the small traces leading to other connections. Replace the tuner shield after complete inspection and soldering. In some cases the eeprom, locationU3201, will need replaced. Might not in your case as you say you can still watch TV and the audio is good. I know this is a lot of information, but this TV can be saved. I have repaired many of these. Thanks for asking and show a few hands of support.

Mar 27, 2011 | GE 31GT660 TV

1 Answer

No video, sound is ok.

If you can take the board out of this TV, you will find many bad solder grounds. First places to look for, are the vertical IC and the horizontal transformer. Be sure to check the solder connections on the small board connected to the picture tube. Very common problem for any and all these tube type TVs. If the vertical IC has bad grounds it would be in your best interest to replace the capacitors near and next to this IC. In any case resolder any and all bad solder connections. Your picture will return in most cases. Thanks for asking and show a few hands of support.

Jan 24, 2011 | Sharp 32C-240 32" TV

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I have audio but only see a white line going across sometimes i hit the tv and i get screen back on and sometimes by itself, what is this?

Sounds like vertical failure. Possible bad connection on the vertical output IC. If you have pretty good soldering skills and a soldering iron with solder you might could try it yourself.

A tv shop in my area would charge around 50.00 or so if its just a connection problem. I say connection because you mentioned hitting the tv to restore the picture.

If you want to try it yourself the connection problem most likely will be on the vertical output ic itself
Its a linear ic meaning straight thin with a one set of leads of 5-7 pins. It will be screwed to a heat sink (metal piece to disipate the heat). It will be soldered on the bottom of the board and most likely there will be cracks around at least one of the pins.. If your not good at soldering I wouldnt attempt the repair yourself..
Good luck!!!

Nov 25, 2010 | JVC AV-27820 27" TV

1 Answer

Flat line on Toshiba tube tv

It could be the vertical output IC, but there may be other possible causes which include:

- bad solder contacts on deflection yoke connectors or dirty connector contacts (on the circuit board and / or on the picture tube neck)

- bad solder contacts on the vertical output IC or associated components (check for little cracks in the solder around the pins, these are so called "cold" or bad / broken contacts)

- power loss to the vertical output IC - check for any burned resistors or other components around that IC, assuming you know which one it is - see which ICs are connected to the wires going to the deflection yokes (coils) on the picture tube neck and check them well.

You need to resolder any bad contacts, clean any dirty pins on the connectors and replace any burnt out components (assuming you can still determine the type or value of the component).

Since you mentioned the problem occurs once in a while, this means that the IC probably fails when it warms up, which can often happen if there are loose connections or bad solder contacts.

Anyway, it could turn out to be a faulty IC, i just suggested a few other things that can be fixed quite easily, and possibly without the need to replace any of the components.


3rq8 (Triarcuate)

Sep 09, 2009 | Toshiba 27AF41 27" TV

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My tv has a line threw the middle of it...the picture will come on but only if you move the tv.

Sounds like you may have a bad solder connection on the vertical ic, it is a small ic connected to a heat sink near the flyback. Usually a 5 pin ic, look on the solder side of the board for a solder connection with what looks like a ring around the pin.

Sep 02, 2009 | Sharp Standard (CRT) Televisions

1 Answer

The television once on has good picture then black rectangular blocks the bottom half of the screen showing only half the picture, very annoying. how can i fix this myself?

look for the vertical section of the printed circuit board.there is a vertical driver ic and it is maybe bad...... either the soldering,or the ic.
if you bang on the tv and the picture regains deflection,there is a bad solder joint or connection.
there are a few capacitors too 100mf 25 volt 4.7 50v also 22mf at 50v

Jul 17, 2009 | Aiwa Standard (CRT) Televisions

1 Answer

Line across screen if i hite it it will work for a some time

If the line of which you speak is a horizontal line that looks like the picture collapsed, the problem is a vertical circuit problem. If hitting the set "fixes" it, then it is likely to be a bad solder connection. If you can solder, resolder the pins on the vertical IC. This is a small flat IC with about 11pins attached to a heat sink that may me marked LA7837 or something similar.

Let me know if that fails to resolve the problem.


Sep 26, 2008 | Toshiba 36A50 36" TV

2 Answers

No vertical sweep on my Sanyo DS31590

This is a fault in the vertical circuit. It can be either a bad solder connection of the vertical IC or a defective IC. If you can solder, you can fix this yourself. Open up the back and locate teh vertical IC. It willbe a small flat IC attached to a heat sink and be marked LA7841. Resolder the pins first. If that fails to resolve the problem, replace the IC. Please note that there may be capacitors in the circuit that need to be changes as well, but without the chip working, it will be difficult to determine which ones. Update this once the IC has been resoldered or replaced with the results and we'll continue if necessary.


Sep 25, 2008 | Sanyo DS31520 31" TV

5 Answers

Mitsubishi 40" tv

i would like to know the model# of the tv..


Jul 29, 2008 | Mitsubishi CS-40503 TV

1 Answer

TV video problem

If you have intermittent line horizontally across both tv screens then there is likely to be bad solder connections on the vertical ic's of both of them. This can be fixed by taking the back off with quarter inch nut driver and carefully sliding the chassis out and turning it up to see the solder side. I don't know the location numbers but the vertical ic will be mounted on a metal heat sink and the connections will be in a row. Sometimes you can see the bad connections. You may need a magnifying glass. I recommend someone who has experience soldering electronic circuits. No solder bridges etc. This is for intermittent (works sometimes) problem on vertical ic. If the line stays then the chip ic is bad along with a 1 ohm resistor off the flyback high voltage transformer. From what you described you likely have bad connections. Hope this helps

Dec 30, 2007 | Standard (CRT) Televisions

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