CCFL bulbs worldwide

Page 4

LCD Backlight Installation Guide

A really comprehensive fitting guide: for a specific system is at the bottom

  • The backlight is an extremely small and delicate Fluorescent lamp and should be handled with extreme care and delicacy

  • Replacing a backlight of ccfl lamp does need some soldering skill, but, is simple to do if you are careful, removing the lamp and replacing it in a notebook lcd is a little more delicate

  • Laptop Screens usually have a metal reflector , but not as often as the larger screens.

Proper handling of backlights and CCFL lamps:

Proper handling of CCFL lamps:

  • The backlight is an extremely small and delicate Fluorescent lamp and should be handled with extreme care and delicacy

  • Pressure or shock of any kind should not be applied to the lamps tube. This may result in Breakage or electrode deformation. (this may cause a leak out of the end of the lamp)

  • Unnecessary heating of the lamps tube should be avoided, as this would break the seal, or break the lamp

  • Stressing at the sealed ends, although invisible from outside, may produce damage to the seals and result in a slow leakage.

  • This destroys the vacuum state inside and makes the lamp useless.

So

  1. Do not impose pressure of any kind beyond 0.25kg on wire ends

  2. Do not twist the wire ends in radial direction

  3. Do not wind the wire ends at the joint ends. If necessary, please fix the wire before winding it at a position 10 mm or more from the ends.

Carefully remove the backlight from the lcd and reflector if necessary, remember it is best to take it out carefully and remember not to touch or stress the tab bonded connectors that connect the front panel to the control panel as shown below (the little tape bits with metal bars on this board)

If you stress these, you will end up with lines on the lcd, if you cannot get the backlight out without opening these up I suggest removing the metal frame and carefully opening the lcd up properly on the bench

Soldering method

  1. Soldering iron: max. 25W

  2. Soldering time: 4 seconds or less

  3. Soldering position: >2-3 mm from the location where the wire comes out of the tube.


Carefully remove the rubber end of the lamp, (show here)

Trim the end of the lamp pins (shown here trimmed) to between 2-3mm of the end of the lamp bulb

Solder on the cable to the end and refit the rubber insulator, (being careful not to break the lamp or get it to warm)

(we will not replace a lamp broken or damaged by the client while soldering or fitting)

Replace the small insulator boot, then reassemble the panel


Required tools

  1. 20-35 Watt Soldering iron with a small tip

  2. Jewellers or electricians fine screwdriver set

  3. Solder paste (or solder, but better with paste if you can get it)

  4. Sharp knife

  5. Side cutters

TX41D56VC1CAA, backlight, ccfl, bulb, tube, fitting, guide, instructions. specifically on the Sony pcg-8a7m, but applies to all of these lcd's, and a guide to many more.

Warning doing these is scary, so be careful and watch my warnings if you do you will be ok.

Not to bad if you follow the rules carefully. (this see a bit long winded, but I have done it this way to make it easy for you to do without asking any questions, and also showing where you may the answers to what would be the problem if you got it wrong)

The bulb you need of course is the following

2mm 334mm 15.4"- 16" Laptop/Notebook Screen For LCD Screen CCFL Backlight LCD florescent tube, bulb

Right Firstly, I am going to do this in simple stages, like teaching babies, so forgive me for being patronising, it is the only way to make sure there are no mistakes.

1. And it is important.

Clean an adequate and well lit flat surface at an easy working height, make sure there are no little lumps, or bumps as you may damage your lcd face.

2. If this is a Sony with a solid state inverter in the coil, any tiny pressure on the inverter will break the coil, and your coil will not work, so your inverter wont work and your backlight wont either, it is not to break two or three of these inverters when installing one of these lcd's with the careless.

picture of the offending inverters below.

We sell them so see our lcd inverter parts site at this link if you need one

The solid state coil is the long thing on the right, just before the ccfl connector.

This is so fragile it is unbelievable, the tiniest pressure will break it & you probably will not notice, but it will stop working.

You may need another before you finish, these are glued in on most Sony's, so removing them by leavening them off is not an option, your only bet (50 50 at best) is to pull it out of the end of the plastic cover without any torque or bending force.

Back to the backlight.

Make sure you clean your hands properly to, you don't want your finger marks on anything that affects the light, or you will have a smudge or dark spot.

You have a few pieces of tape to loosen.

NOTE: you may be tempted to do a full dismantle, don't do that with this lcd you will never get it back together working, only go as far as you need as shown.

1. needs to be lifted from where the arrow is,

You want to avoid pressure in any way, so slip a bare Stanley knife blade gently under a corner to peel it up

Then using the other fingers to keep a minimal pressure uniformly around the tape use two as shown on the left to gently (go slow and the glue will release easily) peel the tape back.

The secret is do not place any pressure on any part of the lcd that is above what is absolutely needed,

Now you see the tape peeled back and to make life easy, I have gently tacked it to the desk to keep it tidy with clear tape, and pulled the backlight cable gently to the side and taped it back safely out of the road.

2 isn't really shown on this one well, but on some syste it will go right over to the arrow, in fig1, which will be lifted the same way as no 1. in this version of the panel it doesn't cover the lcd back

3, and 4, are the Copper foil.

I have shown above another board on top of the tape to allow you to see what you are doing and the safe spots.

Once you have pulled back, (Back is a good way to describe it really, edge a corner up carefully with the blade as shown in the second figure, and pull backwards at a low angle as shown below with the black tape, this doesn't put any pressure on the board, just the tape)

Be careful to keep pressure on the point where my finger is shown with the cable / board interface, this connector is a complete devil, once broken its broken, if you take the cable out you will never get it back in. so keep it flat and safe.

If you are not sure of the lcd, it is safer to try and remove the tape all around but on this one I can tell you where to go.

ON MOST LCD'S there will be tab bonds or other delicate tape that is important to the working of the lcd and is not removable, but in this lcd it is safe to follow me.

ON ALL OTHERS remove the tape don't cut it.

On this system though

Gently mark the borders of the pcb board, with a pen, just feeling the edges,

Don't do the right hand side, or the right hand top as these are more dangerous

Now gently cut the tape around the left hand side of the pcb to release it from the back of the lcd and the panel, (if you are unsure if there is any connectors etc underneath then peel the tape back but on this one on the left there is no connectors)

On the top right there is a little connector with a cable from the front, so here and down the right hand side peel the tape back so as not to damage the cable or the connector.

this bit is ultra important, you don't want the little gold/brown cable / ribbon to come out of the connector, you can if that happens dispose of the lcd so tape it. now good tape strong tape etc

Note: where the tape was removed on the left above where the conductive ribbon connects to the underneath of the board, I have put some clear tape (a few pieces) to make sure that the cable doesn't get pulled out of the connector, that would be catastrophic on this lcd.

Then peel all the tape back along the edge (carefully as shown) you can see where it has been cut along the other side of the pcb, as we know only on this lcd that this is safe on this pcb)

Now the little cable top right side, pull the little white bit out just a bit no more then up as shown. (be careful not to break it off, once off it wont be going back on)

Then dot so much pull the cable away as lift the pcb back and away from the cable.

Now lift the entire pcb board back with the cable still attached at the other end out of the road. (very very important, don't allow this to fall out of the connector or slip)

Making sure not to kink or damage, or detach the cable.

Put a little tape over this side to make sure you don't let it get detached.

Here's one of those connectors, I broke for you earlier (I wish, 300 lost there then) these are a double layer connector, so two rows of connectors, you can see how fine the pins are holding the black connector broken above, and, how small the pads are for the cable to connect onto, (this is about 20x size, so imagine on a double row, how impossible it would be to get the cable back in & align up these connectors, and get that little black retainer back on all in one go. (impossible if you ask me, and I have tried)

Oh, and the cable has connectors both sides as well!

(ok so back to the work)

Now fold back all the little lugs don't be lazy do them all

Now lift up the backlight assembly, complete as shown, making sure to keep all of the layers in place

If you don't keep them in place you will regret it.

now : put the backlight assembly flat face up on your desk, making sure that none of the sheets are out of line.

There are only two cables on the right pull out the white one carefully.

And extract to the end.

Now gently lever up the left edge using a pin, or paperclip etc.

Now lever up all along the way gently, taking care not to bend the tube, (note the bits of tape to keep the layers together, not going past the first couple of mm, they wont be seen there when reassembled.

hold up and away from the plastic frame with a couple of spacers, I have used a fibre pen, and a really good screwdriver, which one of my engineers dropped in the car park, (it was obvious that they weren't paying for them.)

Just the final assembly to do .

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