The LCD TV replaced the CRT — kinescope rel­a­tive­ly recent­ly. Func­tion­al, low pow­er con­sump­tion, and no harm­ful radi­a­tion, such LED and LCD arrays have become pop­u­lar among elec­tron­ic devices and have almost replaced obso­lete devices that use CRTs. How­ev­er, nov­el­ties also break. Var­i­ous mal­func­tions of TVs are not uncom­mon, includ­ing break­downs of LCD matri­ces. In this con­nec­tion, they require replace­ment or time­ly repair. Replace­ment or repair of the LCD matrix can be done by hand.

The principle of operation of the LCD matrix

matrix replacement

An LCD matrix is ​​a work­ing sur­face made of glass with sev­er­al mil­lion pix­els; they change col­or, as well as the bright­ness of their glow due to the influ­ence of exter­nal con­trol sig­nals. Matrix pix­els form the image that we see.

Chips are used to con­trol some pix­els. Chips are called dri­vers that con­trol sig­nals that send a spe­cif­ic sig­nal for each pix­el. Usu­al­ly, con­trol dri­vers are locat­ed on flex­i­ble cables sol­dered into the very base of the matrix glass. This loop can­not be sep­a­rat­ed from the glass, it will also not be pos­si­ble to replace one loop. In addi­tion, it con­tains dri­ver pow­er sup­plies, as well as decoder micro­cir­cuits.

See also - How to repair a TV with your own hands

Matrix malfunctions

Matrix break­downs can be con­di­tion­al­ly divid­ed into the fol­low­ing groups:

  • Mechan­i­cal vio­la­tions (bends of matri­ces, water pen­e­tra­tion, impact).
  • Break­down of micro­cir­cuits and oth­er parts (resis­tor, diodes, capac­i­tor, induc­tance) that ensure the con­stant oper­abil­i­ty of these micro­cir­cuits that form the image. They are on a flex­i­ble non-remov­able cable.
  • Vio­la­tion of a non-remov­able loop
  • “Burn-in” of pix­els that are no longer func­tion­al with­out a mechan­i­cal jus­ti­fi­ca­tion.
  • Back­light not work­ing

The mal­func­tions of the matri­ces described above lead to their replace­ment, since repairs will be too expen­sive or sim­ply impos­si­ble. Replace­ment in this case is a pri­or­i­ty option. For exam­ple, the back­light invert­er for flu­o­res­cent lamps is often locat­ed on the pow­er sup­ply board, while the lamps are also easy to replace. It is more dif­fi­cult with mal­func­tions in the oper­a­tion of LED back­lights, usu­al­ly the man­u­fac­tur­er makes it con­trol on flex­i­ble indeli­ble cables. How­ev­er, here you can try to make repairs with your own hands.

Disassembly of a TV with a front housing system

The prin­ci­ple of replac­ing the matrix depends on the TV mod­el, man­u­fac­tur­er, as well as the dimen­sions of the matrix. How­ev­er, there are gen­er­al rules. There are two pop­u­lar types of case fas­ten­ing — these are screw con­nec­tions and plas­tic latch­es.

The front pan­el of the cladding must be wrung out and the latch­es removed. Then you will see a matrix screwed to the main body of the TV using met­al screws or screws. It is nec­es­sary to unscrew each mount and sep­a­rate it. Be care­ful — per­haps the screws are dupli­cat­ed with latch­es. It will also be nec­es­sary to dis­man­tle the bolts on the back of the TV, they fas­ten the case to a met­al screen that pro­vides pro­tec­tion against mal­func­tions of the pow­er sup­ply, as well as the con­trol board.

case disassembly

When every­thing is done as it should, the matrix with all the elec­tron­ics should be sep­a­rat­ed from the case. In order to pre­vent chips and scratch­es, it is rec­om­mend­ed to place the ele­ment on a soft fab­ric, flan­nel is per­fect for this. Next, dis­con­nect the pan­el from the con­nect­ing cable, be extreme­ly care­ful. In some sit­u­a­tions, for addi­tion­al fas­ten­ing, as well as pro­tec­tion against cable shift, the man­u­fac­tur­er glues strips of adhe­sive tape to the con­nec­tion.

Care­ful­ly remove it, lift the clip — the dog locat­ed on the con­nec­tor, for this you can take small tweez­ers. In order not to dam­age nar­row paths, you need to try to get the cable with­out swing­ing it in dif­fer­ent direc­tions. Then you need to remove the stiff­ness pan­el from the matrix. To this end, we unscrew the screws from the ends, for var­i­ous man­u­fac­tur­ers they can be in the amount of 2 — 12 pieces on one side.

Dismantling the matrix with rear disassembly

This repair has a sim­i­lar order, except that there is no front fac­ing tele­vi­sion frame, but this is part­ly the case, since there are quite a few mod­els, so there are cer­tain tech­no­log­i­cal sub­tleties. In the future, the analy­sis of the con­trol board, as well as the basis for the rigid­i­ty of the matri­ces, is iden­ti­cal. The matrix is ​​mount­ed in the reverse order

When per­form­ing these oper­a­tions, you can make a hint. If for the first time you decide to replace the matrix with your own hands, then it is rec­om­mend­ed to record the actions with the help of a cam­era. On this, in prin­ci­ple, every­thing. Remem­ber and fol­low safe­ty pre­cau­tions, and care­ful­ly fol­low each step when repair­ing or replac­ing matri­ces of a plas­ma or LCD TV.

See also: