68kMLA Classic Interface
This is a version of the 68kMLA forums for viewing on your favorite old mac. Visitors on modern platforms may prefer the main site.
| Click here to select a new forum. | |
| PowerBook 180c LCD Issue – Upper Flex/PCB Connection Failure? | |
| Posted by: BajaTym on 2026-09-19 10:29:43 Greetings, I’m new to this forum, but I’ve been tinkering with older Macs for several years, mostly compact Macs like the Plus, SE, SE/30, and Classic. I’m currently working on a recently acquired PowerBook 180c with a troublesome display issue, and I’m hoping someone here may have experience repairing/reworking their LCD panels. The original display had severe vertical banding that appeared consistent with leaking capacitors. I replaced it with a Sharp LQ9D01 panel that I recapped myself. The severe banding is gone, but I was left with a different display problem. Initial symptoms:During initial power-on, the screen is solid/lit with no obvious degradation. Once the system begins booting, there’s a visible shift and vertical white lines appear.The far-left section (column) of the panel displays perfectly. Across much of the remainder of the screen, the pattern appears to repeat with approximately one correct pixel column followed by one solid white column. Once it appears, the pattern remains relatively stable. Initially, I suspected the display cable, interconnect cable, or possibly something farther upstream in the 180c’s video/display circuitry. So far I’ve:
Narrowing down the problem:After removing the shielding around the LCD, I was able to expose the upper PCB and the series of flex ribbons running across the top of the LCD panel (see video and images).This produced a pretty significant clue. If I gently run a Q-tip across the flex-to-PCB connections along the upper board, the display noticeably changes. In many areas, the affected portion of the screen will temporarily clear up (but not perfectly). Slightly flexing or rocking that PCB produces the same effect. The distorted sections of the display also appear to correspond almost exactly with the individual flex cables running along the top edge of the LCD. In other words, manipulating a particular area of the upper flex/PCB assembly affects the corresponding area of the image. Because of this, I’m now fairly convinced the PowerBook's main interconnect cable and upstream video circuitry are not the source of the problem. It appears to be localized to the LCD itself, specifically the upper flex-to-PCB connections. There is also some dark, gooey residue around several of these connections. I’ve cleaned the accessible surfaces with IPA, but the problem remains. My suspicion is that one or more of these flex connections have deteriorated internally or that the original bonding between the flex and PCB is beginning to fail with age. So, my question now is: "Has anyone successfully repaired (or rebonded) these particular connections on a PowerBook 180c/Sharp LQ9D01 LCD? Or has additional advice to solve this/these issues?" Any help is appreciated. Thanks in advance -- James 👍 Images:   Videos: | |
| Posted by: BajaTym on 2026-09-19 15:22:38 Update: I found a supplier in Japan with Sharp LQ9D01A display assemblies and ordered one. Although the part number and photos match, we’ll see whether it’s truly compatible once it arrives. If everything works, I’ll share the source and cost. | |
| Posted by: Byrd on 2026-09-19 23:04:38 In other LCDs (a Toshiba Libretto LCD) I've had success by creating some sort of shim to elicit pressure on the LCD/frame to make better contact. Where it didn't work was in other random LCDs where I'd had nothing to lose and applied heat; not the greatest idea as it tends to melt the fragile plastic layers. | |
| Posted by: Fred1212 on 2026-09-20 01:05:09 They are available form here https://www.smitacn.com/?country=CN Sharp LQ9D01A LCD Display PanelWe supply original Sharp LCD display panel module LQ9D01A, low price, high performance, you can buy online, both retail and wholesale business.
www.smitacn.com
| |
Posted by: BajaTym on 2026-09-20 11:42:22They are available form here https://www.smitacn.com/?country=CN Excellent! Thank you. The Japanese source claims theirs are new-in-the-box for only $120, and with shipping, it works out to approximately the same price. Very interesting. If the unit I ordered doesn't work out, I'll definitely pick one up from there. | |
Posted by: BajaTym on 2026-09-20 17:37:05In other LCDs (a Toshiba Libretto LCD) I've had success by creating some sort of shim to elicit pressure on the LCD/frame to make better contact. Where it didn't work was in other random LCDs where I'd had nothing to lose and applied heat; not the greatest idea as it tends to melt the fragile plastic layers. Good idea. I'll give the shims/clips a try. If the new display works out, I'll probably go nuclear on the old one and try re-soldering the flex cable. I've never attempted that with a flex cable, but at that point I won't have much to lose. Might as well see what happens! | |
Posted by: Byrd on 2026-09-20 19:20:34Good idea. I'll give the shims/clips a try. Rubber strips or some sort of fabricated metal clip might do and did enjoy your nuclear reference 🙂 Sometimes you have nothing to lose! | |
Posted by: BajaTym on 2026-09-21 05:24:26... and did enjoy your nuclear reference 🙂 Sometimes you have nothing to lose! 😎👍 --- The more I dig into it, the more it seems like this is a fairly common problem with the PB 1xx series Macs. What's surprising is how few discussions there are about it. I've found a few, but they mostly seem to end with replacing the display. Granted, these displays are incredibly obsolete at this point. Still, with this being such a known problem, you'd think someone would have come up with some brilliant/simple way to repair them by now. Of course, the polyimide flex cable doesn't exactly leave us with many options, but it still seems like there should be some way to recover these. What's particularly frustrating is that the display itself is in perfect condition, which makes replacing the whole thing feel like such a waste. All because of a flimsy connection across a cheap-ass flex cable. With a microscope and a really close look, I suspect I'd probably find micro-cracks in some of the embedded traces or the embedded ICs. That's my suspicion at this point, anyway. Thank you for the reply. -- James | |
| Posted by: KGLlewellyn on 2026-10-01 18:44:33 Hey, just want to jump in here, but if the repair of that LCD doesn't work out, could I ask if you were interested in selling the DC-DC board? Mine is a white screen and the ribbon is completely intact - I think some metal shielding got on the interconnect ribbon connector-bit, and shorted out the DC-DC board. But yeah, after recapping, I cannot get any life out of this screen sadly. Other than that, it's in perfect condition. :/ | |
Posted by: BajaTym on 2026-10-03 05:50:28Hey, just want to jump in here, but if the repair of that LCD doesn't work out, could I ask if you were interested in selling the DC-DC board? Mine is a white screen and the ribbon is completely intact - I think some metal shielding got on the interconnect ribbon connector-bit, and shorted out the DC-DC board. But yeah, after recapping, I cannot get any life out of this screen sadly. Other than that, it's in perfect condition. :/Sure, send me a PM. 😎👍 | |
Posted by: KGLlewellyn on 2026-10-03 11:02:47Sure, send me a PM. 😎👍Will do, thanks so much! | |
| Posted by: BajaTym on 2026-10-05 10:22:30 The new display arrived and works well. It’s a new-in-box display from the 1990s and still has all of its original capacitors. They aren’t visibly leaking yet, but the display is ghosting horizontally like mad. I’ve already ordered a set of tantalum caps, so I’ll post another update once they’ve been replaced... Hopefully new caps will solve it.  | |
| Posted by: BajaTym on 2026-10-08 16:26:05 Just a little rant... I have to say, desoldering old capacitors can be a serious pain! After pulling the first one, I discovered a ton of electrolyte leakage underneath.  I've remove all the caps and every single one was leaking. Unfortunately, three of the pads lifted in the process. Thankfully, none were torn off.  Still, what a pain! | |
| 1 |