MBA 13" 2013 i5 1.3 EMC 2632 flashing problem

Hello to all,

first of all i want to say hello to all of the members of this site ! It´s just an awesome forum here. I am really happy to find people where you can help each other.

My question:
I just had a weird problem with flashing a MBA 13" i5 1.3 2013 EMC 2632 with an EFI password. I tried to read the original chip but flashrom didn´t find a chip (message: No EEPROM found !). Than i tried to read the Chip with another programmer---same result !!! Than i grabbed a chip from a donor board just to try to flash the chip with a clean dump. After flashing i removed the EFI password but the machine stuck on Apple logo. After that i tried to read the chip once more and guess what? The same problem... NO EEPROM found. What the hell is going on here? Am i doing something wrong? Can you only flash the chips once? Help would be great !
Any ideas?

Thanks!

what equipment are you using to flash?
are you flashing the chip in-circuit, or are you removing the chip?
if you're flashing the chip in circuit, which adapter are you using?

these chips are rated for 100,000 transactions, you should be able to write indefinitely

if you are writing the firmware from another working mac onto your mac, you need to clean the ME region

for help troubleshooting your NO-EEPROM error, please answer the above questions.
for help making your "donor-board" dump work, please follow these instructions:
ghostlyhaks.com/blog/apple-efi/25-clean-me-region

let us know how you get on!

Thank you so much reverendalc for your reply!

I am using the raspi 3. Also tried the MiniPro programmer.
I read the chip in circuit with no success. Than i desoldered the chip and soldered the wires directly to the pins and tried to read it. No luck! I want to mention something here... when i am trying to read the chip on the MiniPro programmer it shows me the message ( “overcurrent protection“ and “maybe the chip is damaged“ or something like that.
Because i couldn't read the original chip and just clear the Efi password i downloaded the bin file from the repository.
What am i doing wrong?



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Chipset wrote: Thank you so much reverendalc for your reply!

I am using the raspi 3. Also tried the MiniPro programmer.
I read the chip in circuit with no success. Than i desoldered the chip and soldered the wires directly to the pins and tried to read it. No luck! I want to mention something here... when i am trying to read the chip on the MiniPro programmer it shows me the message ( “overcurrent protection“ and “maybe the chip is damaged“ or something like that.
Because i couldn't read the original chip and just clear the Efi password i downloaded the bin file from the repository.
What am i doing wrong?



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Should i plug the charger in when i am reading the chip in-circuit?


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Reading the chip in circuit, do you have an ezflash or competitor clip?

You have to experiment with:
Battery connected, no magsafe
MagSafe connected, no battery
Both MagSafe and battery

I have not determined a rhyme or reason to why what works and when.

When you use the raspi, what is your command? Can you post a screen (or copy&paste) the output?

Also, for the raspi how long are your wires and how are the connected to the chip?

I directly solder the wires to the chip when i am reading the chip in circuit. I will make a screenshot with the output message.

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ok. for troubleshooting, let's consider the raspi.

how have you connected the pi to the chip? how strong is your power supply? how long are you wires?

have you ever successfully flashed a chip with your equipment?

Chipset wrote: I directly solder the wires to the chip when i am reading the chip in circuit. I will make a screenshot with the output message.

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Hello friend "chipset", you can safely use the MiniPro programmer!
If you are welding the wires direct chip pads on the circuit board, you must feed the pin 8 with 3.3v, and pin 4 to GND, only then will be able to read the chip without error!

Browse feed these pins with an external source!

@ reverendalc

Thank you sooooo much ! I fixed my problem! I had a connector on my raspi going to a breadboard and than wires to my chip. Now i connected the wires directly to the raspi and had a normal reading ( to long wires). It´s curios because i read two chips with the long wires without problems but now it´s clear. Thank you for your great help.

@ mario

Thank you, too ! How do you bring the 3,3V to the PIN ? Injecting it from an extern source?

Regards

You can supply 3.3v from any power supply >=1A. Everybody suggests 2A but I always use 1A and have never had a problem with it.

If you program with the pi, it has 3v3 for you. You could also use the pi for power when programming with alternate equipment.

Ok, now it´s clear!

Hope, someone can learn from my experience...

Chipset wrote: @ reverendalc

Thank you sooooo much ! I fixed my problem! I had a connector on my raspi going to a breadboard and than wires to my chip. Now i connected the wires directly to the raspi and had a normal reading ( to long wires). It´s curios because i read two chips with the long wires without problems but now it´s clear. Thank you for your great help.

@ mario

Thank you, too ! How do you bring the 3,3V to the PIN ? Injecting it from an extern source?

Regards

Yes friend from an external source, you can leave a piece of wire spliced the wire that goes to pin 8, and place the feeder 3.3v this piece of wire!

So too do the pini 4 to feed with GND, it is very important not to be corrupt read error!

I advise the amperage in 1A, if you're doing work on the board logic removed from the device without connecting any, only the logic board on the table!

But if you are doing with the logic board in place, or the unit, use the amperage in 2A, so keep the real power in the chip without cargo theft, and have a clean reading and a successful recording.

let us know how you get on!