Fixing the Dreaded iBook Backlight?

Aliencow inquires: "I've recently bought an iBook, and it started having the very common backlight problem. Basically, there are two types of things that can cause the problem: either the screen hinges pinching the cables, which is pretty easy to fix if you're not scared of opening things up; or it could be the logic board, which is what happened in my case. I've heard of someone being able to fix it by doing a bypass operation on the board, soldering a wire before the break and soldering it directly on the backlight connector. Aside from that, however I haven't been able to find much about how to fix that particular problem. Have any of you iBook-owning Slashdot readers had to repair your iBook like this? Any hints? If my repair is successful I'll surely snap a bunch of pictures and make a website, as this is a problem that affects a lot of iBook owners."

Comments

yup, been there, done that

[crahan11]

I had that problem 6 months after I bought my ibook. Closing the lid halfway would make the backlight go off for no apparent reason. At first I thought it was the suspend mode kicking in, but since the little blinking light didn't come on and it started to happen when I barely touched the screen it had to be the backlight. Good thing it was still under warranty. On a side note: I had a problem with one the rubber feet a few months back. It kept falling out so I decided to go buy a new set at the local Apple Store. I was rather surprised to here the clerk tell me that they didn't sell those anymore. If I wanted to have the rubber thingies (or just one) replaced, I'd have to send it back to an Apple Service Center to have it replaced. In the end I decided that a big blob of glue would solve it a bit faster.

Just had the same

[adamgee]

thing happen. Out of warranty. Apple tech told me over the phone its $319 flat rate, including shipping. Clearly this must be happening all the time as the tech didn't even ask me to try any troubleshooting steps. Two days later I got it back and they even replaced one of the little rubber feet that had been missing for some time. Then the number 1 key popped off, but thats another story... $319 for a new logic board installed is not bad. Ever try taking an iBook apart? Not for the faint of heart!

Not for the fainthearted

[mean pun]

The hinge fault and the motherboard fault are more frequently reported, but my previous iBook had a third variant of the problem: the video chip got partially disconnected by a motherboard that flexed too much. Distinguishing this problem from the hinge problem is easy: if wiggling the lid makes the problem appear or disappear, it's probably the hinge, if applying pressure to bottom of the iBook under the left palm rest helps, it's probably the video chip. I don't know how to recognize any other motherboard problems, but if it can be fixed with a bypass it must be a third version of the problem: the loose video chip can only be repaired by resoldering, but since it's a BGA chip that is impossible to do with ordinary tools.

I tried to repair it, but the only thing that fixed it permanently was forcing the control signal of the backlight (a PCM signal) to maximum by soldering a pullup resistor at a strategic point in the lid. I deliberately leave it as vague as this: you really should know what you're doing when you try this, and you should be able to fill in the details yourself. Google is your friend.

Have any of you iBook-owning Slashdot readers had to repair your iBook like this? Any hints? If my repair is successful I'll surely snap a bunch of pictures and make a website, as this is a problem that affects a lot of iBook owners."

Some repairs are documented online, but more are always welcome.

Disassembling an iBook is hard; reassembling it is even harder. Unless you really, really, REALLY know what you're doing, you're shouldn't try this. Even professional repairmen consider it a difficult machine to work on.

If you still want to do it, the procedure is roughly: remove bottom case, bottom shield, top case, top shield to expose the motherboard. Illustrations can be found online, but be prepared for surprises, in particular lots of sticky tape and screws at weird places. Most importantly: carefully document the origin of every screw you remove. I find it helpful to keep the screws from different disassembly steps separate, so that a sanity check can be done for each step of reassembly.

The video chip is located on the bottom side of the motherboard, under the harddisk, but again, resoldering a loose chip requires professional equipment. The wire loom to the display starts roughly under the 's' key, and goes through the left side of the hinge.

iBook G3 not iBook G4

[BMonger]

Just to clarify for the unknowing... this is a problem with the iBook G3 and not the iBook G4.