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.
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:
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:
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:
- Reseated every cable, including the main display flex and interconnect connections.
- Checked continuity through the display flex cable, which appears good.
- Thoroughly cleaned the accessible display connections with IPA.
- Tried the black multi-position switches on the driver board and returned them to their original positions.
- Inspected the boards and connectors for obvious damage.
- Checked the replacement capacitors, which appear to be installed correctly.
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:
Sometimes you have nothing to lose!
