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idonotliketostu
Nov 17, 2011, 01:59 PM
Which pins can I safely short to disable some of the built in memory on the 13" air?



Macman45
Nov 17, 2011, 02:03 PM
Which pins can I safely short to disable some of the built in memory on the 13" air?

First, why would you want to? Second you don't specify which model of MBA? The design and system boards of the MBA changed significantly with the advent of the SSD.

I would not want to poke around with ons on the board of a modern MBA

johnhurley
Nov 17, 2011, 02:36 PM
Which pins can I safely short to disable some of the built in memory on the 13" air?

A tablespoon of salt mixed with an ounce of h20 should do the job.

Macman45
Nov 17, 2011, 02:37 PM
A tablespoon of salt mixed with an ounce of h20 should do the job.

Can't understand why the OP (Or anybody) would want to do it in the first place?

Skika
Nov 17, 2011, 02:51 PM
But srsly... why?:confused:

idonotliketostu
Nov 18, 2011, 03:00 AM
But srsly... why?:confused:
attemp to reset efi pw on first gen air

Any hardcore electrical engineers out there?

johnhurley
Nov 18, 2011, 05:51 AM
attemp to reset efi pw on first gen air


Take it into an apple store if anyone is remotely close to you.

TheRealDamager
Nov 18, 2011, 07:46 AM
attemp to reset efi pw on first gen air

Any hardcore electrical engineers out there?

Agreed with the last poster - you are seriously in over your (or any other Air owners) head. You need to hit the Apple store.

idonotliketostu
Nov 18, 2011, 10:59 AM
Agreed with the last poster - you are seriously in over your (or any other Air owners) head. You need to hit the Apple store.


Many things can be solved by going to the apple store. This is not one of them.

jdechko
Nov 18, 2011, 01:13 PM
Many things can be solved by going to the apple store. This is not one of them.

Apple seems to disagree...


Resolution

If you cannot remember the EFI firmware password for your MacBook Air, please schedule a service appointment with either an Apple Retail Store or an Apple Authorized Service Provider.

Source (http://support.apple.com/kb/ts2391)

Also, consider the possible outcomes:

You take it in to Apple, they can't fix it, they replace it.
You try to fix it, you short out the Logic Board, you pay to have it fixed.

idonotliketostu
Nov 18, 2011, 02:17 PM
From the genius service manual: "replace the main logic board"

TheRealDamager
Nov 18, 2011, 02:48 PM
Many things can be solved by going to the apple store. This is not one of them.

Whoa there - just trying to help. Shorting out random pins on your logicboard may seem like a logical and rational way to proceed to you, but you are likely alone there. Next time I'll ignore your questions rather than be called condescending and ignorant for trying to help. Good luck to you.

oneMadRssn
Nov 18, 2011, 04:48 PM
attemp to reset efi pw on first gen air

Any hardcore electrical engineers out there?

I'm an engineer (albiet not with a specialty in computer hardware).

Have you looked at the logic board where the memory is? Those pins are tiny and very close together (we're talking mils here). I wouldn't go near them with an average radio-shack soldering iron. That will likely desolder 10 pins at once, and warp the board form the heat.

Unless you have a microscope and a very very fine-point soldering iron (even better if it's CNC controlled), then you will likely fail. If you do have access to that equipment, then you will need to track down some documentation that will explain which pins do what. There are usually two pins that need to be connected while booting to reset the EFI memory. Traditionally the motherboard manufacturer clearly labels these pins. I doubt that is the case inside an MBA. An internal Apple repair manual might have that information for debugging/refurbishing purposes.

My advice is also to not attempt this. Even with the right equipment and documentation, you're odds of success are less than 50%.

idonotliketostu
Nov 18, 2011, 06:42 PM
I'm an engineer (albiet not with a specialty in computer hardware).

There are usually two pins that need to be connected while booting to reset the EFI memory. Traditionally the motherboard manufacturer clearly labels these pins. I doubt that is the case inside an MBA. An internal Apple repair manual might have that information for debugging/refurbishing purposes.




I know the layout of the logic board but not looking to desoldering a chip.

Just need some advice on disabling it temporally whether by shorting power supply to the chip or some method keen to an engineer.

MacModMachine
Nov 18, 2011, 08:12 PM
I know the layout of the logic board but not looking to desoldering a chip.

Just need some advice on disabling it temporally whether by shorting power supply to the chip or some method keen to an engineer.

efi password can be reset by taking a wire and connecting two tin pads on the logic board, shorting out memory will just ruin the logic board....not reset anything.


ill see if i can locate the location on the logic board for you.

idonotliketostu
Nov 18, 2011, 08:38 PM
efi password can be reset by taking a wire and connecting two tin pads on the logic board, shorting out memory will just ruin the logic board....not reset anything.


ill see if i can locate the location on the logic board for you.


sweet :cool:

altecXP
Nov 18, 2011, 08:51 PM
the rEFIt shell has a command called dmpstore which allows you the clear all or parts of the NVRAM.

chrono1081
Nov 18, 2011, 08:59 PM
No offense OP but its pure stupid not to take this to an Apple store. It doesn't matter what you read in a genius service manual, that is just a guideline. If/when you screw it up you'll be out an air. If you take it to Apple and let them handle it and they screw it up, you get a new air.

sdsvtdriver
Nov 19, 2011, 04:21 AM
No offense OP but its pure stupid not to take this to an Apple store. It doesn't matter what you read in a genius service manual, that is just a guideline. If/when you screw it up you'll be out an air. If you take it to Apple and let them handle it and they screw it up, you get a new air.

Maybe there's a reason why someone wouldn't want to take a machine into the Apple store... that has a password... that they do not know.

TheRealDamager
Nov 19, 2011, 09:46 AM
Maybe there's a reason why someone wouldn't want to take a machine into the Apple store... that has a password... that they do not know.

Thats exactly what I'm thinking.

MacModMachine
Nov 19, 2011, 11:20 AM
Thats exactly what I'm thinking.

only thing i can think of if its stolen....which in that case the apple store wouldn't care anyway....apple has never cared of stolen items.

chrono1081
Nov 19, 2011, 12:07 PM
Maybe there's a reason why someone wouldn't want to take a machine into the Apple store... that has a password... that they do not know.

I thought the same thing but I didn't want to say it since I got warned recently and didn't want to risk another :P

idonotliketostu
Nov 19, 2011, 03:05 PM
No offense OP but its pure stupid not to take this to an Apple store. It doesn't matter what you read in a genius service manual, that is just a guideline. If/when you screw it up you'll be out an air. If you take it to Apple and let them handle it and they screw it up, you get a new air.

Waste of time, there are no geniuses that would go out of their way and not follow guidelines. He'll be liable and probably be rebuked by the store manager. Besides, it's out of warranty and they won't even touch it unless it was a dead simple fix.

The macbook air is already out of commission, so there are no negatives to learning and trying new things on the logic board.

No, it's not stolen. Lay off of the skepticism.

Lets get back on topic shall we and stop suggesting that I bring it to the store.

chrono1081
Nov 19, 2011, 03:35 PM
Waste of time, there are no geniuses that would go out of their way and not follow guidelines. He'll be liable and probably be rebuked by the store manager. Besides, it's out of warranty and they won't even touch it unless it was a dead simple fix.

The macbook air is already out of commission, so there are no negatives to learning and trying new things on the logic board.

No, it's not stolen. Lay off of the skepticism.

Lets get back on topic shall we and stop suggesting that I bring it to the store.

Wow aren't you rude to people who were trying to help you.

idonotliketostu
Nov 19, 2011, 04:26 PM
Wow aren't you rude to people who were trying to help you.

How was that rude :confused:

TheRealDamager
Nov 19, 2011, 07:01 PM
How was that rude :confused:

Thats the core of the problem - you don't even see the problem. Once again - good luck to you.

cw3x3
Mar 19, 2012, 05:46 AM
Hi all, first post and hope there is a solution.
Okay, late 2010 macbook air, glitched OSX installation that freezes at initial apple boot-up screen. Has efi password (set by seller) and so I dont seem to have any options to correct problems, ie:cdrom boot, etc., or key-combos. Ive been using this notebook for a little over six months without issue and being my first macintosh i simply pushed the power button and everything worked - what i heard and why i wanted a mac! Ive read alot of different posts and tried to educate myself as best i could on this issue and now Im thinking I either got totally duped into buying a notebook with a very expensive problem or worse, possibly stolen notebook. After reading a few other posts like this one, i thought i should check the serial number and make a few phone calls. its partially worn off (rubbed off?) and so was then weighing jail terms against money lost - no brainer there - but read about the 'two jumper pads' in this post above and, back to my initial reasoning, would be able to read the serial number from the operating system, recover my personal and work files, determine the notebooks status and - if needed - pursue the seller and my money back before turning it over to the local boys in blue. The notebook has an ssd hard drive (stick?) and a very different interface from ide 'pins' or sata 'slots' that im a bit familiar with. My first thought was simply remove the hard drive and let 'others' figure out its status. Any help or suggestions would be very much appreciated

pianogregor
Jun 13, 2012, 07:10 PM
So, after a few days searching i just found your argueing ībout the password reset for the air.
As my problem is different i excuse myself for entering with the argument that i wheter find at last a solution or throw my logicboard away.

I ****ed up my Macbook pro early 2008 A1150 (intel)
with a tool called ONYX, i used this tool several times in this last 4 years, but as
my macbook started to hang around in shutdown and dislikes to stay in sleep (no, not cause of usb devices, thanks)
i asked the ONYX to clear all : caches, indexes, temp files, etc.
it asked me back to reboot between some actions, but as some profound selfconsiousness of mine i told it to work through, i would start later :cool:.
It did what i sayed, but....
oh surpise, :( after the reboot my logicboard was instantly ****ed up :eek:..
..indeed it was a surprise, i thought, "in worst case i set up a fresh install of osx" so WTF.
Now, to shorten the story: THE TECH DETAILS:

1. No Hardware Problems at all, before using software ONYX
2. After the reboot, NO BOOTING - Power for HD+DVD+FANS+SLEEPLIGHT
3. no Screen, no Backlight, no Boot-peep, no further HD-Action, nor possibilities to Network boot or DVD boot
4. RESETS: SMC, NVRAM, (and PRAM) (there wherenīt any reactions to it) everything about 5 times
5. openend the MCB and disonnected and reconnected every cable (I tested if it reacts on disconnecting the temp sensors =YES - so its still kind of working)

and now 6. :apple: APPLE Service wants 700€ for a new logicboard and work, and seems to have no idea what else could be done except changing the stuff to a new one, very boring of these guys..

here it comes to the end:
I get a used one for less than 500 bucks, so what do i want
..-> its hurting me that the problem seems so near to me, cause it should be just a software ****ed EFI in my midclasstechie view.
It should be not a big deal. Should it:confused:

POINT -> Is there a way to reset or flash the EFI hardware based, like shorten pins (I didnīt locate it yet at all) ?

I think thats it. Ah yes, indeed I did all updates, so there always was the newest version in the EFI, but please donīt ask me which one, the last one 2 weeks ago that was allowed to come with 10.6.7.
:) Thanks for any supportive idea
Otherwise the ebay gets the parts........and me an very fat disillusion ;)
greets

ZipZap
Jun 14, 2012, 07:02 AM
Whoa there - just trying to help. Shorting out random pins on your logicboard may seem like a logical and rational way to proceed to you, but you are likely alone there. Next time I'll ignore your questions rather than be called condescending and ignorant for trying to help. Good luck to you.

I think many of the posts here come off as condescending.

You know nothing about the OP but assume he's an idiot. Perhaps he is an engineer and using an old MBA for some a typical purpose.

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Wow aren't you rude to people who were trying to help you.

I see very little help here.

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Thats the core of the problem - you don't even see the problem. Once again - good luck to you.

Condecending.

load97
Jun 14, 2012, 07:07 AM
waste of time, there are no geniuses that would go out of their way and not follow guidelines. He'll be liable and probably be rebuked by the store manager. Besides, it's out of warranty and they won't even touch it unless it was a dead simple fix.

The macbook air is already out of commission, so there are no negatives to learning and trying new things on the logic board.

No, it's not stolen. Lay off of the skepticism.

Lets get back on topic shall we and stop suggesting that i bring it to the store.

x2.

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Wow aren't you rude to people who were trying to help you.

Including you, they are not helping. Who cares if someone wants to tinker & learn a little in the process. For all anyone knows, it could be a school project.

pianogregor
Jun 15, 2012, 06:46 PM
Hey guys, donīt you wanna stop this. Itīs boring.

So if he doesnīt get his password recovery, fine. bye to you "idonot..whatever"
The thread is anyway from last year, so what?

Cause it seems that here is someone reading, i ask, whats about my question.
is there a chance to repair a software broken efi chip with shortening some pins or something special other trick?