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Debutante
Jul 24, 2006, 05:31 PM
Hi All,

So what I thought would be a quick fix on my PB 12" Aluminum (867Mhz) has given me days of frustration. After I cracked the LCD on my PB G4 12" Alluminum (Model A1010), I tried find my way around shelling out $350 for a new lcd. The original LCD was a Samsung LTN121XJ-L01. After surfing Ebay for a while, I mangaged to find a completely new Samsung LTN121XJ-L02, which is essentially the same LCD with a different suffix (L02 instead of L01). I assumed that this would not matter at all since the LCDs are identical, but after swapping out the old cracked LCD for the new one I was completely bummed to see that new LCD dead at birth. I get no response from the LCD, unless I hook up the backlight wires of the new LCD to the old inveter and then connect the LCD flexcable to the old, broken LCD. When I do this, the backlight functions and the new LCD turns grey with no image. I've already reset the PMU, PRAM and NVRAM. I don't know what else I can do. Is this LCD completely incompatible with the old one? I don't see why it wouldn't be. Ideas?



aquajet
Jul 24, 2006, 07:11 PM
How did you damage the first LCD to begin with? Perhaps something else was damaged as well?

Debutante
Jul 24, 2006, 07:19 PM
How did you damage the first LCD to begin with? Perhaps something else was damaged as well?

The first LCD was damaged with a pressure crack, but it was fully functional, save the crack and missing about 1/4 of the image. so, the problem _should_ be isolated to the LCD and nothing more.

xfiftyfour
Jul 24, 2006, 07:27 PM
i have no idea about compatibility, but it sounds like you're not 100% sure, either. perhaps you could try calling samsung or apple themselves and see if anyone can help you determine if the new LCD should work?

if not specifically that, try to find out what changes were made between the -L01 and the -L02 and see if any of those might explain why you're having issues?

aquajet
Jul 24, 2006, 08:09 PM
It's difficult to say in your situation. You might try contacting Apple, see if they would be willing to let you discuss the issue with an engineer. Perhaps they'll clue you in as to the exact LCD models used in the 12" PowerBook. I believe Apple used panels from a number of companies.

You might also check with Samsung. Perhaps someone can explain the exact differences between the -01 and -02 models.

Beyond that, I don't know what else to tell you. I wish you good luck trying to fix the issue. :)

Debutante
Jul 24, 2006, 09:09 PM
could the flex cable be different? i'm looking closely at this one and i see 19 small wires withing the flex cable... maybe the LCD only resonds to a different flex cable?

Debutante
Jul 24, 2006, 09:51 PM
This is interesting. On Samsung's website, only the LTN121XJ model is listed. There is no listing for the L01 or L02 suffixes... So, by this logic, the LCD _should_ be the same regardless of the suffix... Or?

http://www.samsung.com/Products/TFTLCD/NotePC/LTN121XJ/LTN121XJ.htm

REDSRT4
Jul 25, 2006, 11:18 AM
i have never done one myself but i have watched some techs swap out screens and i would say 50% had issues. Never seemed to work 100%

tekmoe
Jul 25, 2006, 12:46 PM
have you tried hooking back up the old screen to see if it still having the same issue? that might tell you if the new panel could be broken or not.

wish you the best of luck.

Debutante
Jul 25, 2006, 01:16 PM
Old screen is not having the same issues. The computer will recognize the old screen, however the new one will not start up at all. It will light up if the backlight wires are connected to the inverter and the flex cable is connected to the OLD LCD at startup. Very odd. So, the problem must be with the flex cable or something. I have no idea.

playaj82
Jul 25, 2006, 01:51 PM
There might be a problem with the inverter being compatible with the LCD screen itself. I've been going through hell and back to find the right inverter for my friend's HP laptop.

mcgivervii
Jan 17, 2010, 11:44 PM
This is a very old thread but if I found it maybe others will need the information. The pinouts for the LTN121XJ-L01 and L02 are different, and the l02 has the first 4 pins or so swapped.

L01 L02
Pin 1 - VDD 3.3 Volts Pin -1 VSS Ground
Pin 2 - VDD 3.3 Volts Pin -2 VDD 3.3 Volts
Pin 3 - VSS Ground Pin - 3 VDD 3.3 Volts
Pin 4 - VSS Ground Pin - 4 VEEDID DDC Power 3.3 Volts

the rest of the pins don't match either but these are the important ones.....
they will blow out the supply transistor on your motherboard if it isn't fused.

I know this not from an Apple Clamshell but from a Dell X300 notebook. It uses the L02 and the apple uses the L01. hope this helps.
BTW.... if you rewire the connector with the correct mapping it might but you have to cut and number all 20 wires and match them up. the pinout for the LTN121XJ-L02 is found here: http://www.beyondinfinite.com/library.html


GOOD LUCK