How to | Board Swapping

BOARD SWAPPING is one of the easiest TV repair techniques, but one should be well-informed when going in to ensure safety and efficiency. Herein I will outline my general procedure when doing a board swap to be certain that things go as smoothly as possible. 

WARNING: Advice and instruction on this blog is to be used at your own risk. That is, you should understand that TV's operate using high voltages and can be dangerous to work with. As part of your preparations, you should unplug the set and let it have enough time to discharge (at least 15 minutes). If you are not comfortable with the repair or feel that you are not qualified to be nosing around inside the TV, DO NOT proceed. Seek professional service. The few dollars you save by doing it yourself are not worth risking your life.

1) Prepare a flat surface with something soft (towel, carpet scraps, etc.) that will not cause damage to your LCD or PDP panel. In my shop, I have a carpeted rolling bench for servicing TV's up to 60".

My work bench in my electronics shop.

2) Lay the TV down on it's face carefully, with the base stand (if attached) hanging off of the edge. You may wish to grab a friend when dealing with larger units or plasma displays (which tend to be a bit on the heavy side). 

Lay the TV face down on the prepared surface.

Pro-tip! I don't know about you, but I eat a lot of eggs because they are cheap, tasty and good for you. Even if you don't eat a lot of eggs, you can at least get through eighteen (18) of them in a reasonable amount of time. I use the egg cartons to hold my screws, usually cutting the cups into sections of six (6). It's great for keeping things organized! I've had a lot of experience with TV's and know which screws are used for what just by looking at them, but you may find it helpful to label where things go on a separate sheet of paper. 

Egg carton with labels.

3) Figure out how the base stand is attached and remove it. This LG has four (4) screws that hold the base stand on and then it slides right out.

Removing the base stand screws.

Base stand slides out.

4) Carefully remove all of the screws from the back cover, noting what type they are and where they go. You may have to remove a 1/2" nut around the coax connection on some sets, and keep in mind that there are other special cases as well. This LG is pretty cut and dry, but it doesn't hurt to have an assortment of tools or a multi-tip screwdriver and a set of bits. It's come in handy more than once for me, and was fairly inexpensive. You don't need Snap-On tools when you're working with electronics.

*NOTE* Do NOT use power tools when working with electronics. You will strip screws and break plastic components. If you are especially unlucky, you'll end up destroying traces on a circuit board, which kind of defeats the purpose of you repairing the TV in the first place!

5) Gently pry up and remove the back cover, taking care not to snap plastic tabs or otherwise damage the cover. Go slowly, it's easy to miss screws! 

Lift up the cover. Don't break anything!

6) Now that we're inside the TV, locate the part you wish you replace. Today, I'm doing a PSU swap, but as you can see, the MAIN BOARD (the one with all the inputs on it) would be a bit more of a pain to get to. If there are extra covers/brackets/etc. all you have to do is take it slow and steady and if you are not confident that you can remember how it goes back together, get out your cell phone and snap a quick photo or two.

The PSU is on the left side, and the MAIN PCB is under the metal cover on the right.

Today, I'm removing the PSU.

7) Remove all of the connected harnesses from the board headers, taking care to realize how each one works. This red power plug uses the locking tab style mechanism, and requires a small squeeze and then can be lifted out. Others have no tabs and can simply be grasped firmly and pulled from the board. Be careful not to bend pins or break headers.

The red harness is plugged into a 2-pin header on the PSU.

Squeezing the tab.

And it pops right off.

Notice the difference between the top (tab-less) and bottom (with tab) harnesses.

Without a tab to depress, just grip this firmly...

...and pop it out!

8) Take out the screws holding the board down and gently lift it from it's mounting location. 

Remove the screws holding the board in place.

Once all fasteners and cables are removed, lift out the board.

The board is removed!

9) Congratulations! You're halfway there! All you have to do now, is go in reverse. I'll let you go ahead and finish up on your own. Go slow and don't forget any screws! If something in this tutorial is unclear or you need help with a specific situation, please contact me. I'm here to help. Good luck on your future repairs!

Repair Journal | Samsung PN50B650S1F

Samsung PN50B650S1F | 50" Plasma

SYMPTOMS: TV fully functional, with the exception of HDMI ports 1, 3 and 4. When devices are plugged into any of the three inputs listed, the TV reports "no signal."

DIAGNOSTICS: Since everything works on other inputs, we can assume that the MAIN PCB is at least somewhat functional, but the fact that all other functions of the set are working means that it is an input issue, and therefore a MAIN PCB issue.

SOLUTION: Board level repair? Heck no! Not unless you're smarter than me, which you might be, and let me know if you figure it out! However, it is my preference in this situation to just swap the board. It's an easy repair and won't cost you all that much. Go ahead and skip over to ShopJimmy for parts! If they don't have them, you can always contact Samsung at 1-800-SAMSUNG and navigate to their parts department for pricing.

Refer to the BOARD SWAPPING TUTORIAL if you need assistance or feel free to contact me. Thanks!

Repair Journal | LG 50PA6500

LG 50PA6500-UA.AUS | 50" Plasma 

SYMPTOMS: Relay clicks, but the set will not power on.

DIAGNOSTICS: This is a power supply issue and is a common problem with this model, as reported by LG. If you are having this issue and your TV is less than a year old, please contact LG's warranty department right away and get this fixed for free.

SOLUTION: Either A) Get the board replaced I/W via LG or B) Swap out the PSU yourself.

As always, I endorse ShopJimmy for all of your TV repair needs, but if you cannot find the parts there, contact LG directly! If you need help with board swapping, please feel free to contact me. Remember, always be safe when performing your own TV repairs, and be sure to unplug it from the receptacle and let it discharge!

Is it my MAIN PCB?

Hey all! I have been getting a lot of questions that end up pointing to the MAIN PCB, so I figured I'd do a post on "what might point to a problem with your MAIN PCB (main board, mother board, etc.).

• Some inputs function perfectly, others do not.
• This means that everything else in your TV is functioning fine. It is receiving proper power from the PSU and it can successfully display a picture and play audio on some of the inputs. The When some inputs are out, while others are still okay, you can assume it is the main board.
• Examples
• My coaxial connection is grainy while everything else works fine.
• There are four HDMI ports and only HDMI 2 will display a picture. HDMI 1, HMDI 3 and HDMI 4 all give me a "no signal" errors.
• The picture isn't quite right
• Sometimes you have a situation in which the picture is the wrong color, skewed, or otherwise "not quite right." All of the settings you change in the menus can't fix it and you are frustrated! That's okay, it might be your main board!
• One thing to mention here is that if you have an LCD TV and there are VERTICAL or HORIZONTAL LINES going through the picture, whether they are thick or thin, you might be looking at a faulty T-CON board or loose LVDS cable (connects the T-CON to the MAIN PCB).
• One last tip! If you are running COMPONENT VIDEO (RGB video and RW audio cables), check to make sure you plugged everything into the correct jack (socket), it's been known to happen. If you switch up the video cables by accident it will definitely result in a very interesting color palette. 
• The audio track is non-existent on all inputs. 
• Wow, what a nice picture! It's absolutely beautiful. Look at that 10000:1 contrast ratio. Oh wait a second, why can't I hear anything! Am I deaf? Is the TV muted? No! What the @#%$! Chill out. Sometimes the cables come loose. Check the connections on the speaker terminals and between the speakers and the main board first, as well as making sure the speakers aren't blown out. You may want to check your connections on the back of the TV as well. A loose cable or one that hasn't been plugged into the correct socket has fooled people more than once. If not, it might be that the main board is faulty and simply cannot process the audio signal.

Anyway, if you think it might be the MAIN PCB giving you trouble, feel free to ask! I'm here to help. Always include the MODEL code with any request to help me best answer your questions!

Repair Journal | LG 32CS460-UC.AUSYLJM

LG 32CS460 | 32" LCD TV 

SYMPTOMS: TV functions normally, except the coaxial input (ANT.) shows a picture that is black and white and quite grainy.

DIAGNOSIS: This is a problem with the TUNER on the MAIN PCB.

SOLUTION: You may try to purchase and replace a TUNER if you wish, but my suggestion is to go the safe route and buy a MAIN PCB for this set here.

DIY INSTRUCTIONS: This is a simple board swap. You will likely only need a philips #2 screwdriver. It's helpful to have a bit set just in case, though.

1) Prepare a soft surface (table with towel down or similar) and place the set on its screen with the base stand hanging off of the surface. Make sure the unit is unplugged and allowed to sit for about 15 minutes to discharge. You don't want to have a run-in with high voltages.
2) Remove all screws from the back cover, making sure to double check for ones you may have missed. Note the size and type of screws you are pulling out. Some may be machine screws, course thread (for plastic), etc. They will need to be put back where they came from in order to assemble it correctly.
3) Gently pry up and remove the back cover.
4) Locate the MAIN PCB (it should be easy to find, as it has all of the RCA plugs, HDMI plugs and other inputs on it). If you have the new board, simply compare it to the ones inside the TV. You won't be able to mess it up!
5) Remove all necessary wire harnesses (noting where they go) and screws, then remove the old board.
6) Place the new board in the TV and replace all the screws. Plug the wire harnesses into the appropriate headers.
7) Taking care not to touch any components inside the TV, you may wish to plug in and test the television at this point. If you don't feel comfortable with it, at least install the cover with a few screws before testing.
8) Once it is known that the unit is functioning properly, reassemble the TV and put the base stand back on.
9) Enjoy the satisfaction of a DIY repair!

*NOTE* If you wish to ask any questions or have a comment, feel free to post here or e-mail me directly.