Replaced LCD, Screen Missing Pixels, 6 vertical lines missing

[cupcakesandaudi]

I replaced the Cluster Center LCD in my 2001.5 A4, I'm decent at soldering and when I hooked everything backup, I'm missing 6 vertical lines on the screen. I was told by the vendor of the screen that I probably screwed it up, so I took it apart, checked the solders, touched them all with some flux and 63/37 electronics solder, checked them and the same problem, no change at all.

Do you think the LCD is defective or did the cluster go bad in the repair?

IMAGES:

http://img267.imageshack.us/i/img20110124215944.jpg/
http://img593.imageshack.us/i/img20110124215917.jpg/

Sorry for the horrible images but you should get the idea. The missing lines are visible even when the LCD is powered off via the stalk button, you can see shadows of where they are not "activated" or in any way powered.

[walky_talky20]

I don't know, but that looks a heck of a lot better than mine. I pretty much can only read it between 50-70F. Any colder or hotter and the pixels are all wishy-washy.

How much did you pay for the screen, if you don't mind?

[cupcakesandaudi]

With the amount of work I put in, and that it was a new screen, the result I was expecting was "perfect" ;-)

Not at all, I paid about $75 from a vendor on ebay.

[mpower]

Soldering is one thing... The ribbon cable is very sensitive when you are bending it and trying to position/line up the solder points. Also, when finished soldering and placing the metal bracket that secures the LCD to the rest of the back-light source one has to be very careful as the ribbon cable is very fragile and can be easily damaged. At this point it seems that you damaged the ribbon going from the contacts to the LCD panel itself. Try to take the metal bracket off and see if you regain some of the lines/pixels, then put back on very carefully. Also, check your soldering (flashlight under the main board) to make sure that no two contacts are bridging...

[cupcakesandaudi]

...At this point it seems that you damaged the ribbon going from the contacts to the LCD panel itself. Try to take the metal bracket off and see if you regain some of the lines/pixels, then put back on very carefully. Also, check your soldering (flashlight under the main board) to make sure that no two contacts are bridging...

I will do this - do you know, are all the contacts supposed to be independent or are a few of them supposed to be bridged (shared ground/power)?

Any other things to check when I pull it out again?

[mpower]

All contacts are independent... no bridging... How much extra solder did you put on the contact pads? When you apply to much solder the contacts will easily bridge. You might have mix of issues with bridged contacts and ribbon damage. You will have to take it apart again and recheck your work. Also, you don't have to completely reassemble the cluster to check the LCD.. Just plug the very left (blue) connector to the board with the LCD soldered. You will not damage the cluster and will know right away where you stand. Wearing a computer antistatic grounding strep might also be a good idea when handling the board itself.

[audifirst]

the lcd you bought did it have orange ribbon ?

[cupcakesandaudi]

the lcd you bought did it have orange ribbon ?

yes, it does.

[audifirst]

yes, it does.

then you wont be able to correct the problem, these are the Chinese LCD, the problem lies in the ribbon contact to LCD these tiny gold plated ink dyes are problem , under pressure once you install the metal cage they brake down , if you remove the metal cage and put pressure on the ribbon you will get all pixels back, one you let go pixels return. there is no fix for that other then contact your supplier and ask him for another unit if he is willing to ship to you. if he does sent you another unit, in order to avoid another failure is to cut the metal wing cage on the left side the part that touches the ribbon ,
if he doesn't want to ship it , then you have to live with it or you can get better LCD that you won't have these issues, cost a bit more but you get warranty.

[Audi_A4_]

Man those look a lot better than mine. i have no idea what mine is supposed to say

[chris164935]

then you wont be able to correct the problem, these are the Chinese LCD, the problem lies in the ribbon contact to LCD these tiny gold plated ink dyes are problem , under pressure once you install the metal cage they brake down , if you remove the metal cage and put pressure on the ribbon you will get all pixels back, one you let go pixels return. there is no fix for that other then contact your supplier and ask him for another unit if he is willing to ship to you. if he does sent you another unit, in order to avoid another failure is to cut the metal wing cage on the left side the part that touches the ribbon ,
if he doesn't want to ship it , then you have to live with it or you can get better LCD that you won't have these issues, cost a bit more but you get warranty.

Since we are on the subject, where can a non-Chinese LCD be had from?

[audifirst]

Since we are on the subject, where can a non-Chinese LCD be had from?

Check my signature first link , they have it

[cupcakesandaudi]

the problem lies in the ribbon contact to LCD these tiny gold plated ink dyes are problem

I will check this and the other suggestions and report back my findings with new photos if there is a change. The vendor maintains my solders are bad, would like me to send it in to them, which isn't really an option.

ninja edit: Thank you all for your suggestions.

[audifirst]

I will check this and the other suggestions and report back my findings with new photos if there is a change. The vendor maintains my solders are bad, would like me to send it in to them, which isn't really an option.

ninja edit: Thank you all for your suggestions.

that is easy blame for him, that's sucks, I remember that he had warranty his product I guess he got tired of this and removed warranty from ebay, so you left on your own
what you can do, is strip the cluster to board insert into car and just power on without turning car on and use tooth pick or other non-metallic tool and apply pressure on each pin and see if pixels lines disappear if it does fixes apply more solder to those pins, other way to check on the bench use microscope or magnifying glass and saw needle and see if each pin is solder just touch on it and see if it moves, don't remove just yet until you check that,
once you verified that this didn't work then only try to remove the metal cage and power up and see if the problem is gone, but I can tell you that there is no fix, I know a lot of guys who use Chinese lcds because they are cheap and they are fed up with it I know couple people who told me that every time they buy batch of 40-60 pieces at least on avg 20-40 pieces are bad , they have to buy large amount in order to find good working lcd ..

[cupcakesandaudi]

... strip the cluster to board insert into car and just power on without turning car on and use tooth pick or other non-metallic tool and apply pressure on each pin and see if pixels lines disappear if it does fixes apply more solder to those pins ...

Done, all solders look good, or they're really bad, but pressure makes no change.

... other way to check on the bench use microscope or magnifying glass and saw needle and see if each pin is solder just touch on it and see if it moves, don't remove just yet until you check that,
once you verified that this didn't work then only try to remove the metal cage and power up and see if the problem is gone, but I can tell you that there is no fix...

Definitely don't have a microscope or a particle accelerator or a nuclear reactor, but removing the cage and repositioning the cable definitely did the trick. I have some photos and it's clear that the contact between the ribbon cable and the LCD itself is defective.

NOT WORKING


Working with straight cable.


I'll let you know what I do about this.

[DRock3d]

I got a chinese LCD, it didn't work for shit. So I did research and pixelfix showed me I bought a shit LCD. Then I decided to go with an S4 cluster because I like the colors better and the LCD works perfectly! And I got it for $100 so it was worth not sending my unit in for repair or buying another (possibly bad) LCD.

[spindoctor]

yes, it does.

so the Chinese versions only come in orange ribbon? Anything else I need to look at?

[audifirst]

so the Chinese versions only come in orange ribbon? Anything else I need to look at?

yes the chinese lcd come with orange ribbon,

[audifirst]

Done, all solders look good, or they're really bad, but pressure makes no change.



Definitely don't have a microscope or a particle accelerator or a nuclear reactor, but removing the cage and repositioning the cable definitely did the trick. I have some photos and it's clear that the contact between the ribbon cable and the LCD itself is defective.

NOT WORKING


Working with straight cable.


I'll let you know what I do about this.

I can tell you that there is not much you can do the contact between the ribbon and lcd is gone, I have photo i took under microscope of the area and it shows broken traces that unfortunetly they can not be repaired

[audifirst]

here is the photo of the lcd you have under microscope, this is back side of the lcd
you can see on the left side the traces are broken counting from the left first 8 traces are broken then 9 has contact then trace 10 and 11 has broken contact and these are responsible for horizontal lines once you straight out the lcd and ribbon the pixels return

[Audi_A4_]

What about this place here?


http://www.modulemaster.com/en/servi...t_clusters.php

[audifirst]

What about this place here?


http://www.modulemaster.com/en/servi...t_clusters.php

from what I have seen they use Chinese lcd,

[cupcakesandaudi]

So the endgame is that even confronted with images that clearly show the defective LCD, the company still asserts it's my fault. They kind of suck, but dumb on me for getting the knockoff one. I didn't want to mention it immediately in case they decided to make good. They told me to tear out the defective one and send it back and they would consider giving me a refund. Feel free to disagree, but I was not interested in de-soldering and leaving a giant gap in my cluster while relying on their goodwill.

I've made a workaround by cutting out some of the white shrouding to allow the ribbon cable to stick out - it's been working now for the past 1.5 months. I'm stoked to have it working, but too bad I had to go through such an ordeal.

Moral of the story, BUY THE GOOD OEM quality LCD, not the Chinese made knockoff.