[crouchingtiger]

My friend's Powerbook Titanium G4/550 recently started exhibiting the following symptoms: the screen would "fade" away and show garbage. The computer itself would still be totally fine but the screen would no longer show any updates. Fiddling around with the hinges would momentarily show the screen again but then it would go away. The problem has gotten worse and now it is nearly impossible to get any image to show up.

1) It does not appear to be a problem with the computer itself. Hooking up to an external display works great.

2) It does not appear to be the backlight. The display brightness keys work fine.

3) The LCD itself seems fully functional because every so often a full image WILL show up.

Am I correct in surmising that this is a problem with the video cable between the LCD and the Powerbook? If so, would a part like this:

titanium video cable
work for the repair?

We've taken the Powerbook into two service centers and they've both recommended replacing the entire LCD assembly at a cost of $700+ so obviously replacing the cable alone would be more attractive. Does anyone have any experience with this sort of repair?

Thanks!

[romeosc]

If you have safeware.com insurance its afree fix... if not the cable will probably work, but it could be just loose, but opening the screen is not for the squeemish! It is glued and screwed! BE CAREFUL!

[vinster]

Originally posted by crouchingtiger:
My friend's Powerbook Titanium G4/550 recently started exhibiting the following symptoms: the screen would "fade" away and show garbage. The computer itself would still be totally fine but the screen would no longer show any updates. Fiddling around with the hinges would momentarily show the screen again but then it would go away. The problem has gotten worse and now it is nearly impossible to get any image to show up.

1) It does not appear to be a problem with the computer itself. Hooking up to an external display works great.

2) It does not appear to be the backlight. The display brightness keys work fine.

3) The LCD itself seems fully functional because every so often a full image WILL show up.

Am I correct in surmising that this is a problem with the video cable between the LCD and the Powerbook? If so, would a part like this:

titanium video cable
work for the repair?

We've taken the Powerbook into two service centers and they've both recommended replacing the entire LCD assembly at a cost of $700+ so obviously replacing the cable alone would be more attractive. Does anyone have any experience with this sort of repair?

Thanks!

I've had a similar problem recently with my Pismo. A series of thin, purple lines appeared on the left side of the screen and garbles the display. This seemed to happen only when the machine got hot at first, but the anomaly started to appear more regularly as time wore on.

I tried many things to fix it including tapping the display area, checking both ends of the video cable and the connectors on the inverter board but no luck. The anomaly even appeared after letting the components cool. I could get the artifacts to disappear by using a LCD tester called Pixel Check to turn the screen a single colour until the lines disappeared but whenever I did something that worked the processor, such as repair permissions or install something using the Apple installer program, the ugly lines would reappear.

Yesterday, I couldn't get the anomaly to go away. It would flip back to a normal display when I turned the LCD to a single colour in Pixel Check but immediately come back when in normal use. I started to think that there was some kind of weird EMI or other interference causing this to happen, so I dismantled my Pismo down to the inverter board and did a couple of things.

First, I took some plastic kitchen cellophane and wrapped it over the taped area of the inverter board. The original tape was open at the ends. Secondly, I put some clear tape over the logic-board side of the inverter board as some of the plastic had come away from one of the small white plugs at the ends of multi-coloured cable connecting the inverter to the logic board.

I powered up my Pismo again and the lines were still there but they quickly flickered away and the screen returned to normal. The lines haven't reappeared, yet. I haven't had a chance to heavily use the processor which always made them appear, but am hopeful that I've finally fixed the problem.

So, perhaps your friend's problem is with the inverter board. This component has to convert direct current electricity into alternating (ie. vibrating) current and generates EMI, thus the presence of dampening tape. Sealing up the inverter board seems to have worked for me, fingers crossed, maybe it will for your friend, too.

Good luck!

[MM-o4]

I had a work mate had the same problem but he hammered his hinges HARD. Paint all chipped off etc... As a mac user that cried when my powerbook had tiny weeny scratch on it, I felt like taking it off him for such horrible treatment of a PB.
He even had scratches all over his screen. I asked him how they got there and he didn't know. I couldn't believe that, but hey it's his PB.
He still had warranty and Apple repaced to whole screen+hinges.
Big fix with no warranty. I think thats why the attachment is different on the ALs.

MM-o4

[MountainMac]

I'm having the same problem with my PBG4 400. Haven't figured out a fix yet, other than connecting to an external monitor. I think I'm going to use this as an opportunity for an upgrade.

[Macola]

Identical problem with a Ti400. Replaced the inverter board but that didn't fix it. The only solution is to get another LCD, you can probably find one on eBay. I just use it now with an external monitor.

[crouchingtiger]

thanks for the help guys, I appreciate it.

It's good to know it's probably not the inverter because I'm not having exactly the same problems as vinster describes and the backlight seems fine.

No one has tried replacing the video cable itself? I did find some details on the procedure on the net (powerbooktech.com) and I guess I can understand why!

I guess we'll just end up using it to drive an external display but it seems like kind of a waste of a perfectly good LCD screen. Also, I understand the hinges might be worth something -- maybe I'll try posting on the marketplace in a few days when I have this all sorted out.