Does anybody know what goes wrong on the logic board that causes it to not turn on?I'd like to attempt to repair mine and not replace it if at all possible. Original black mackbook 2.0 ghz. Been told by apple it is the logic board and I need it replaced. I would like to know what exactly is going bad and causing all the failures on these boards.
Powerbook G3 Wallstreet 233,IMac G3 233 Rev.A Bondi Blue,
Mac OS X (10.2.x)
could be any number of things. there are a lot of parts on a logic board!
There is someone in brooklyn that works on these, even if they have spill damage. if he gets it going, it's about $225 with return shipping, but if you are in NJ, might be cheaper or you could even drop off / pick up. goes by g4 cube king parts on ebay & also sells refurbed boards with exchange.
http://shop.ebay.com/merchant/g4cube_king_parts_W0QQ_nkwZQQ_armrsZ1QQ_fromZQQmdoZ
He did fix my board for a black 2.2ghz macbook. didn't get to see what he did, there was a mix up when he boxed & shipped - actually sent me a new board from apple (same specs, but for a white macbook, ports are gray) he had for whatever reason. the board was his & offered to swap me back if I really wanted to. I told him it was ok, wasn't going thru the trouble of sending it back. there are plenty of good reviews & even a couple people on this forum that used his services without issue.
If I need to again, I'd still be sending him the board.
I see, does anybody know exactly what the logic board repair people do? I mean I see on eBay people offering there services for liquid damaged logic boards. What are they doing? What are the common peices on the logic board that fail. Is there an achilles heel on the logic board if you will.
Having serviced Apple portables and replaced logic boards, there's not much on it that's modular. Outside of the fan, heat sink and cabling, everything comes already mounted/soldered to the logic board. Without knowing specifically what's causing the board to not properly POST the machine, it's probably (ultimately) quicker and cheaper to just replace the whole board.
Look, I know for a fact that people repair water damaged/failed boards. There are ads all over eBay and in the classifieds for Macbook logicboard repair. I want to know the process for identifying what is wrong on the motherboard. Can somebody that has repaired these boards tell me that process. I don't want to hear "just replace the board" because thats not what these places are doing.
the process seems to be the "secret sauce" for sucess - telling people what it is would kill their business. this is how they make money. I don't fault them for that. if they can do the same job cheaper & is the same result, I'm all for it.
Well I'm dedicating this thread to the "secret sauce". I will keep this thread alive until I get some anwsers. Somebody with knowledge on this kind of thing must post here!
I don't know if there is a common thing that fails with the MacBook logic board but I can tell you a common thing that fails with most printed circuit boards. Solder connections fail. I have found that to be the case with a large number of devices I have repaired. I had a Kanga (Powerbook G3) logic board that had 13 cracked solder joints on the legs of RAM ICs. After resoldering the board was good as new.
I just discovered a broken surface mount diode by resolder all the joints on a circuit board. The board worked if it was flexed just right but failed otherwise. I could not see a problem so I just started resoldering all joints. When doing one end of a SMD diode half of it fell off the board!
Solder joints fail for two reasons generally. One is that expansion and contraction due to thermal cycling eventually can crack them. Another reason is that they sometimes are very marginal from the factory.
The way to trouble shoot for this problem is to use a very good magnifying glass with a good light source and visually inspect every joint possible. You can't necessarily see all of them.
Another method is to remove the casing (keyboard in the case of the MacBook) and power the device, or at least try. Try flexing the board in various ways while trying the power it on. This can make an otherwise questionable or failed connection make contact, at least for a while, and the device may again work. The important thing is to try to make your results repeatable before you draw any conclusions.
Another technic is to vibrate the circuit board with a tool such as an etching tool (rubber tipped of course) to try to get a failed solder joint to make connection temporarily. Another technic is to heat or cool the board while in circuit by using a refrigerator or hot air gun (hair dryer).
The bottom line is, I have found it to be rare to have an actual component such as an IC fail unless the device was subjected to abuse such as high voltage from a nearby lightning strike for instance. I have found it far more likely to be a failed connection, whether that be a solder joint, loose cable or other connectors.
It is generally cheaper to replace an entire board than to pay someone $75 an hour to trouble shoot it. BUT, if you are doing the trouble shooting yourself it is far cheaper to do so and much more gratifying when you find the problem. Your cost is usually going to be nothing more than your time spent.
Thanks a whole lot Gregory! This is exactly the type of information I am looking to compile in this thread! I know that the solder connections do fail a lot which results in having to replace a whole board. See the ibook G3 graphics chip problem. Now that i see how it is practical for Apple, but not for the average user to replace their logic board because of obvious reasons like maybe...$! Anybody know how to repair water damaged boards? Anybody know what those eBay ads claiming to fix logic boards that are water damaged do? Anybody have any other suggestions for do it yourself logic board repair? Any more ways to trouble shoot the board? Lets keep this going!
I tried reviving one after a fancy coffee spill - had sticky goo all over it. Bought the machine this way, I've never dumped on one personally.
Got some rubbing alcohol from the store & tried to clean it with cotton tips. It had no effect, still just sat there with the white LED on, no chime or screen, but the HDD would spin.
A liquid spill typically means going through the keyboard. Cleaning a circuit board is relatively easy but cleaning a keyboard is not at all easy. But still, to clean a circuit board you just about have to flush it with water. Merely cleaning that what you can see or access with a Q-tip is only part of it. Residue underneath components can easily conduct current between the various conductors.
I have not had the MacBook keyboard apart but I have had a number of Powerbook keyboards apart. If they get liquid in them they are ot going to dry out any time soon. They have to be completely disassembled till you get to the electrical contact area. This needs to be cleaned with distilled water, then dried and reassembled. Cleaning the logic board without cleaning or replacing the circuit board is not likely to work.
don't disagree with that as I stated that these boards are very complex. This was a 1 shot deal with me, I wanted a machine that I could fix & carry with me that wasn't a white macbook or a cheap windoze machine.
The boards are very complex and I'd like to learn as much as I possibly can about them. There doesn't seem to be much on the web about this kind of thing.
mwall614 wrote:
The boards are very complex and I'd like to learn as much as I possibly can about them. There doesn't seem to be much on the web about this kind of thing.
About what kind of thing?
I don't suppose you are going to find a schematic of the MacBook logic board but there is all kinds of info on the technology of printed circuit boards. For starters, try Wikipedia.
Here are some answers to some of the questions that have been raised here. I have been in the Apple Computer repair business for more than 20 years. I founded and ran a company called Pre-Owned Electronics and now I have started another company called MicroReplay. Our company specializes in repairing Apple logic boards.
When you spill liquid on a computer and it gets on the logic board, the minerals and salts in the liquid immediately begin to eat away at the metal and fiberglass that the board is made of. If there is a power source available, such as a battery, which is supplying power to the board (even when the computer is turned off), the electric current will interact with the liquid and accelerate the corrosion process. This will cause the copper and other metals to migrate all over the board.
If you spill liquid on a computer, unplug immediately and remove the battery. This will help slow the process. Even still, there is usually a BIOS or PRAM battery on the board which supplies power to the board to keep the clock and other settings while it is off. This battery will also drive corrosion. I don't want to make this sound like an ad, but the sooner you get the unit to a properly equipped repair facility, the better.
The first thing we do with a liquid spill logic board is clean off whatever the liquid is. This is done correctly by cleaning the board in an immersion bath with industry-standard chemical solutions and using high-powered ultrasound to remove all the contaminates. This step is essential because unless you get all the liquid off, even from under the chips and other devices, the corrosion will continue and the board will -- guaranteed -- fail again. Without the ultrasound, there is no way to properly clean a board.
The next step is to repair any damage to the circuit board itself. This includes damaged masking, substrate damage, corroded etches and missing or damaged pads. Then we look for missing or damaged devices which must be repaired or replaced. These devices are truly tiny -- some smaller than gnats. These steps are performed using a high-powered microscope and specialized soldering equipment. We also use specialized chemical compounds to repair the board itself.
Finally we might need to replace some of the Ball Grid Array (BGA) or QFN devices like the video processor, memory controller or some of the various power regulators or other chips. This step is done using specialized equipment which allows us to remove, align and replace these devices. The equipment allows us to subject the devices to an exact time/temperature profile which we develop during the R&D process for each board. These are very expensive stations, usually costing $25K or more each.
Once we get a board to post, we run it though a burn-in process to make sure it works. We then put a six month warranty on it and ship it out!
-Joe
MicroReplay
31 Dunham Road #1
Billerica, MA 01821
Voice: 978-262-1340
Web: www.microreplay.com
I may receive some form of compensation, financial or otherwise, from my recommendation or link.
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