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Johnnya101

Powerbook 140 Lines on bottom half of screen and clicking sounds

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Mission success in transplanting a 160 display cable to my 140!

 

Screen is super duper bright and contrast and brightness work... well... like new! Screen is crisp and clean for the most part. But of course, like always, theres an issue. The bottom half of the screen has lines on it, but ONLY the bottom half! Bad screen, logic board, cable...? Cable has good continuity so I would hope its not that. Hope this is a known and easy fix? Also some ghosting on the top left. Looks like what would happen on an unrecapped LCD.

ALL CAPS REPLACED on LCD and inverter (You can tell. SUPER bright screen! :) ). RECAPPED PSU!

 

Also I noticed that after not using the speaker for a minute, and if I go to the sound control panel and change the volume, theres a loud click right before it plays the sound. I also noticed just messing around in the OS there is a click once in a while. ??? Is it just warming up after decades of rest? No battery installed.

 

SHNldBs.jpg

EOWGIuR.jpg

SjNwGSF.jpg

Edited by Johnnya101

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Better photo. My phone keeps putting the photo out of focus as you can see above.

 

Reseated the ribbon cable to LCD. No change. Tried shaking the thing a little and flexing the cable. No change. Caps all appear to be correct polarity.


Really hope this isnt a bad screen... Speaker still clicks every now and then. Adjusting contrast and brightness dont do anything with relation of the lines.

 

Edit: Apparently after some research the ghosting is normal for a pasive matrix, and mine looks far better than some. Doesnt bother me, just was wondering. But those darn lines do! :(


Edit Edit: Could it be the inverter? Got that recapped though. Would an inverter do this?

 

89MYXKX.jpg

Edited by Johnnya101

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Reseated LCD cable on the inverter AND LCD itself. Nothing.

 

Edit: Is a 160 inverter compatible with a 140? Maybe I should swap them out and see what happens. I really dont think its the ribbon cable since I tested for continuity. LCD doesnt appear to be the culprit either just from looking at it. After looking at Apples service manual. Apple seems to think the LCD or interconnect board. No mention of the inverter. Also mentions a display cable shim, but this cable seems to already have one, plus its a tight fit...?

Any ideas?


Edit again: Inverter on a 160 has different outputs. Interconnect board looks different too.

Edited by Johnnya101

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Well, the inverter after Ive looked into it some more only controls backlight and contrast. So thats out.

 

That leaves the interconnect board, LCD, maybe cable (Even though its been tested?.

 

At this point I've tried reconnecting the video cable (both ends) multiple times, pressed around the border of the LCD to see if there's a bad connection in it, smacked the screen to check for a loose connection. Nothing has done anything. The screen is exactly split in half. Surely someone can pinpoint what to check next? I have a known good 160 I can swap the display cable from but I'd hate to have to dismantle my third Powerbook within 24 hours.

Edited by Johnnya101

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I can post a photo of the entire LCD later today. It was kind of corroded before recapping, but my recapper appeared to have cleaned most of it up. I'd hate for this to go to waste.

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Yeah. Also like I said in PM - and I will say I'm no electronics engineering expert and could be totally wrong about how this works - I think there logically should be a multiplexer or demultiplexer IC on the board to handle the input and send it to the correct line on the screen. It might have a bad connection to one of it's pins.

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Ok folks, here is a photo of the front and back of the LCD PCB.

 

Jinnai, I'm not too good with electronics either , but have any idea where abouts that stuff is?

 

In the meantime, it's buzzing time.

 

VaTo4Oq.jpg

kb9k7xb.jpg

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Haven't found anything obviously wrong. Just wiped it down a little more with alcohol and a qtip. Guess I'll try and see if that little amount of cleaning made a difference. Looking more like one of the ics might be bad.

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Well, lets look at the chips we can read. The LA5316 chip is a Variable Divided Voltage generator. I can't read any other chips, but I would look for chips between the LCD ribbon coming from the main unit and the bottom half of the LCD, and Google their model numbers to see what they do.

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I've tested all of the connections, all good. I'll just list it up for sale, I'm not really good with this stuff.

 

Jinnai, if ya want a project 140, it could be yours! Lol.

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@TechEdison Here are some better photos of the area I would presume you were talking about. See anything off? Are these side cables the ones responsible for what Im seeing?

(Note: Any whiteish residue is from me attempting to clean with alcohol)

(Bottom of panel is bottom of LCD installed)

lq4uBk6.jpg

(Bottom of photo is bottom of LCD installed)

97eefBR.jpg

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@TechEdison

 

Heres a better photo. What do you see wrong in the first photo? The second? Theres a strip of glue that runs down the side that covered those components, giving them the dirty look. Its just glue.

 

sprnylU.jpg

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Also, the top circled area is the top part of the screen, so I dont think its related to the issue.

Another photo

 

VMXN6Sb.jpg

Edited by Johnnya101

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Wait a minute. Are you seeing this?

84Jme2j.jpg

 

Lets look a little closer...

TKSijh6.jpg

Theres a speck of solder shorting out that trace, which was worn down to copper, allowing it to bond and potentially short out that trace. It checks out, its on the bottom half of the LCD. Ill see what I can do. Definitley does not looks like it is supposed to look like that.

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PRAISE THE HEAVENS! THE SKY HAS OPENED AND LIGHT HAS SHINED THROUGH.

WOOOOOOOOOOOOOOOOOOOOOOOOHOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO

 

9UPnp6e.jpg

 

WWOOOOOOOOOOOOOO

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20 minutes ago, Johnnya101 said:

whoever soldered this capacitor shorted this trace (I accidentally added this text box and can't remove it on my phone) 

Oh no, I have failed you! :( I'm very relieved you found a solution, but I'm definitely sorry I didn't pay more attention to the trace damage. 

Edited by Jinnai

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It was an honest mistake! I really didnt think it was your doing at all. I just happened to noticed the exposed copper traces and then saw a little dot of solder shorting out a trace. I forgive you! Amazing work otherwise.

 

Im happy to have a fully working PB140 now! Gotta unstick the hard drive, its jammed and clicking. All simple stuff from here on out. The speaker clicking seems to have been software related, I dont hear it now that there is no OS to load.

 

So happy it was something little like that. Now a fantasticly sharp LCD can be used once again.

 

 

If you take a look at my previous photos, you will notice what appears to be a dead pixel on the bottom left corner. Its gone now too, all related I guess?

Edited by Johnnya101

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Ok, so a couple of questions...

 

First of all, the connor hard drive seems to have kicked it. It spins up, spins down, spins up, etc. Never boots. Got it to boot once but now it wont stay spinning. Swapped it out with another connor. THis one doesnt even show up in HD SC. Are these fixable? If not, should I just drop in an SCSI2SD Powerbook edition? Kinda pricey at $80.

 

Secondly, the speaker clicking seems to be consistent with drive usage, When I boot from a floppy, there are a few clicks and as soon as the desktop is loaded, they stop. Is this a power adapter issue or logic board thing? Power adapter has been recapped.

 

Heres a glamor shot of me attempting to install 7.0.1 only to find out the drive is dead. Really sharp screen. Faint line in the middle but Apple says thats normal.

S0oziOG.jpg

 

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Congrats! Glad you took another closer look at it.

 

The line in the middle is indeed normal. It is the split point between the top and bottom half. Like I said above, the passive matrix displays are split in 2 to help with rendering.

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Now I have to see why it clicks sometimes and what I should do for a hard drive. I'm thinking an SCSI2SD Powerbook edition. Anyone have experience with those?

 

As for the clicking, I've tried a different power adapter and there was no difference. I wouldnt rile out though both drives being bad and sucking a bunch of power causing the speaker to click.

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