iBook G4 Logic Board vs. DC In Board Failure

Question

iBook G4 Logic Board vs. DC In Board Failure

Would a logic board failure completely shut down the computer or allow it to keep operating?

My iBook's power cord stopped working abruptly and after the existing battery life depleted, it died.

I had a similar problem 18 months ago when the DC In board stopped working but it failed intermittently before completing dying.

When I took my computer to the Apple genius, he said it is the logic board that has failed this time. He seemed to believe this because he used a known good power source to charge the computer and a new, charged battery and neither would power up the computer.

However, I am not sure he's right about the logic board because when the power cord stopped charging, the computer kept functioning as normal while operating off of the battery. Would a logic board failure completely shut down the computer or allow it to keep operating for a limited time?

iBook

Posted on Jul 1, 2011 9:14 AM

Reply

Answer 1

Jul 1, 2011 11:28 AM in response to measureformeasure

Hi, and welcome to Apple Support Communities.

Would a logic board failure completely shut down the computer or allow it to keep operating for a limited time?

It depends on which part of the logic board failed. I had a defective logic board which did not allow the iBook to run from the battery at all. This board was a replacement board supplied under AppleCare. They had to take it back and replace it again.

So, a logic board can fail in a number of ways.

When the battery won't charge, there are four possible problems. Listed in order of frequency, they are:

The battery
The adapter
The DC-in board
The logic board

When it's the DC-in board, the iBook should run from a charged battery. So, I would tend to agree with the Apple Genius in this case.

Reply

Answer 2

Jan 16, 2012 8:44 AM in response to measureformeasure

I have had this same problem--the iBook will operate off the battery but not charge it (despite the computer recognizing that an adapter is plugged in). It stays on fine until the battery runs out. I can charge the same battery in another iBook with the same adapter, and that is fine, so I put a new DC-IN board into the defective iBook. It made no difference, so sadly it would seem that the logic board is the next, well, logical culprit. That will be significantly more expensive than a DC-IN board, so this may be the end of this iBook. 😟

Reply

Answer 3

Jan 16, 2012 8:56 AM in response to Clint Paden

This is a different problem from that of the original poster. His iBook would not run from the battery at all, charged or not.

On your iBook, I would suspect that the replacement DC-in board is defective.

Reply

Answer 4

Jan 16, 2012 9:47 AM in response to Ronda Wilson

Rhonda, I did miss the part of the Apple store guy trying a new battery.

As for me, I would hope that a brand new DC-IN board would not have the same problems as mine--are there known manufacturing defects?

Reply

Answer 5

Jan 16, 2012 8:20 PM in response to Clint Paden

Where did you buy the DC-in board? Many places sell ones that are pulled from iBooks that are no longer working instead of brand new ones.

Reply

Answer 6

Jan 17, 2012 4:45 AM in response to measureformeasure

I got it from ifixit.com--it is listed as "used" but looked in good condition (not that that means anything)--it did have new adhesive on the bottom of the cable.

Reply

Answer 7

Jan 17, 2012 5:38 PM in response to Clint Paden

I got it from ifixit.com--it is listed as "used"

I think that is your answer. You may want to contact iFixit and see if they will replace it.

Reply