I am new here and this is my first post. I have tried many ways to fix the audio of my Macbook and nothing made it start working..No sound at all during startup etc. From authorized apple service center here, they squeeze cash to repair and their only solution is to replace the logic board for this!! All I can tell is that the problem is in the logic board and where I could find the Audio area?? And if there is a problem in a resistor etc, is it possible to get one.. I have the Macbook 1181 schematic that details everything..It says there are 4 parts under AUDIO and they are CODEC, SPEAKER AMP, JACK and JACK TRANSLATORS. From where I could find these and the connectors on the logic board. All I see are the connectors are labelled as "J7302" (For left hand speaker connector) and "J7303" (For R/H speaker)...I can send the pictures of the logic board so if there is any Avionic or and Engineer/Tech that knows, please guide me out and let people like us know to familiarize the logic board and there unit,parts, connectors etc..
Comments
First I would reset the PMU/SMC. Do this by powering off the computer, and then holding the power button in for about 20 seconds -- it should make a loud tone, and the sleep light should flicker. If it doesn't make a tone but the sleep light flickers, that's a good sign that you really do have a board issue, because it should always make that tone. Not seeing the sound hardware in the OS could conceivably be an OS issue, but resetting the PMU/SMC and failing to hear the tone clears up that question nicely. If you DO hear a tone, but you don't get sound in the OS, you might try wiping/reinstalling the OS, or booting to another volume to rule out your OS as the issue. Resetting the PRAM also couldn't hurt, although I don't think it will tell you anything as conclusively as resetting the PMU/SMC.
Have you opened up the computer? I'd take off the topcase, and examine the board carefully with a flashlight to see if you can spot corrosion due to liquid damage. If you find any, clean it off with 90% rubbing alcohol and q-tips, or a soft toothbrush. Also, make sure the speaker cables are fully seated, although it would be odd for both of them to be disconnected, etc.
Unfortunately I am not an expert at logic board repair, so if it comes down to a board issue and there is no corrosion to clean up, my abilities stop at that point. However, AB Cellars is on the site occasionally, and he has become quite an expert at this sort of thing...he may be able to advise you further, or even repair your board for a fee, if you send him a note. But keep in mind there is not necessarily a fix -- there are as many ways a board can be damaged as there are boards, and very often it's just not realistic to bring them back from the dead...especially an A1181 board that only goes for $150 these days.
Good luck!
John
You are going to need special probes for your test equipment so you are certain that you are only touching 1 "pin"/connection at a time. I soldered sewing pin to each of a set of probes. You are going to need an LCR meter that tests in circuit or you are going to need to remove components off the board to test them. You will need something to test impedance, some LCR meters do that, the datasheets will contain the measurements you should see. I suggest you use a stereo microscope. You might get by with a 10x magnifier on a stand.
Personal opinion: You are better off replacing the board and selling this one to recoupe some of the money. Another option would be getting a USB audio card to get sound.