Fixing Universal Board In SHARP LED TV LC24E156M
This is yet another case that I had the chance to attend to during my periodical visits to my techie friend who focused on panel bonding works. The mother board of this TV was beyond repair due to a lightning strike (another natural friend for technicians whose income dependent solely on electronic service! Other natural friends are lizard, fungi, rats and sometimes even snakes apart from power supply surges!) The suggestion for fixing a universal board in the TV was accepted by the customer and I was given the task which I undertook with a lot of joy, like a child getting an ice-cream Choco bar! (LOL)
The first and foremost thing to do was to check whether the backlight would work well. For that, we need to provide a power on potential, tapping it from the 12V through a 10K resistor. Sometimes, in sets like Sony, we may have to connect power dim, and any other backlight adjusting connections also without which backlight would not get switched on in such sets. When this was done, the backlight was not working as the LED driver had got affected. So, a universal LED driver board was provided and checked, upon which the backlight was found working very well. So far so good! For connecting the panel to the universal board, we need 12V supply, LED backlight connections [LED+, LED-, Power on], speaker connections [left and right channel with the ground wire], control panel connections [IR + Power on indicator LED connections]. To begin with, I provided two long wires for 12V supply [+ and ground] that would reach the UB (short form used for Universal Board) which would be fit on the outside of the back cover. Then soldered three wires to the universal LED driver board [+, ground and power on] ensuring that the length would reach the UB. Then joined the two black wires of the speakers to make it one and soldered one red (for Right channel) and white (for Left channel) wires making sure that these three wires would reach the UB. From the control panel, IR pins were traced for 5V supply, ground and data output. Same was done for LED. These wires were also extended to reach the UB. All wires were put labels in order not to make any fatal mistakes while joining to the UB. The jumper setting was adjusted for 12V panel. It has provision for 3.3V, 5V and 12V. This is very important.
Next job is to make space for fitting the UB holding case. It has a bottom and a lid, which can be easily screwed on to the back cover. In order to ensure that the case sits firmly and properly so as to enable input connections such as USB, AV and HD, a piece of the top of the slot were cut off. Then all these wires were soldered to appropriate places marked on it and UB was fixed firmly. The cut piece was glued on from the bottom later to cover the open area. The LVDS cable was long enough to reach the panel. We need to check the power supply side of the cable both at UB and panel and match it properly. You can follow my statements very easily from the following pictures: (Please use control and upward arrow for zooming)
Then the power was applied, after rechecking all connections. My friend adjusted the resolution and other essential settings such as backlight blue on standby, directly getting on without a need for remote operation etc. The picture was damn good! You can see the result yourselves:
The back cover was fixed after testing it for some time and the set was left on continuously for aging test.
Mission accomplished adding satisfaction to the bag! As for me I earned experience and money too!
This article was prepared for you by Parasuraman Subramanian from India. He is 72 years old and has more than 30 years’ experience in handling antique equipment like Valve Radio, Amps, Reel Tape Recorders and currently studying latest tech-classes conducted by Kerala State Electronics Technicians’ Association. He has done graduation in BBA degree, private diploma in Radio Engineering and retired as MD of a USA company. Presently working as Consultant to Hospital and other institutions.
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Albert van Bemmelen
March 24, 2023 at 11:25 pm
Very professional repair as usual. Although zooming in on the photos is something that helps understanding what boards were used in this repair the details were rather vague. And since none of the used parts were mentioned in detail it is like with the repairs about using the many different existing universal power modules, that are often mentioned but hardly ever in detail shown, for me difficult to follow. Therefore I sadly still wouldn't know what modules to buy that were used in this and similar repairs.
Parasuraman S
March 25, 2023 at 5:13 pm
You can buy U11 boards for LED TV. These are available with two HDMI ports and smart version also. I have already covered this type of replacement before. A few more might come. A lot of videos are available in Youtube. Similarly universal LED inverter boards are available with multiple pins and sockets.
Waleed Rishmawi
March 25, 2023 at 2:48 pm
I never done this kind of repair. when the board is beyond repair or cost too much to get it fixed I just replace it with the same board I got get from other technicians in my area. thanks for sharing though and have a blessed day
Parasuraman S
March 26, 2023 at 12:21 am
The reason why I do not use a second-hand board from technicians, is because of the risk of buying a board without knowing its background; i.e., how long it was working, what was the reason for failure, was any tampering or other modifications done, how long it was off the circuit etc. There is every chance of such a board failing soon. Customer has to pay through their nose for such an original board without any definite guarantee! Whereas new boards are reliable and we can give a warranty of three months comfortably.
Waleed Rishmawi
March 27, 2023 at 5:43 pm
Parasuraman: I understand your concern but I do not do anything unless the customer agrees to it and knowing the risk. many of them agree to this and so far their TV is still up and running. the guy I get my borads from has a reliable source and usually gives me about 1-2 months warranty on every board and usually it works just fine. of course I got over the board making sure all is well before buying then i test it out about one week in the shop. so far no worries. have a blessed day
Parasuraman S
March 27, 2023 at 11:08 pm
Unfortunately, such a flexibility is not there here. We have to pay full money in advance, get it and if it is found defective on checking at our end, we may have to absorb the cost! That is the scene here. The sellers just don't care. Now for the technicians, they might pass on a board without knowing whether it is working or not. And usually, we cannot press for a refund or replacement in either case. Very sad situation. Many thanks for your comments and inputs!
Yogesh Panchal
April 1, 2023 at 12:33 am
Excellent!Sir
Waleed,In our country for any electronics parts there is On-Counter Testing only no further warranty once you leave the counter.
Parasuraman S
April 1, 2023 at 9:52 am
Many thanks for your comments!