MBP summer 2009: downgrade EFI from 1.7 to 1.6 ?

[macchiato2009]

Hi

i'm a bit frustrated about this problem with EFI 1.7

I realize that even SL will not fix this issue as this is related to the firmware, not the OS...

i was wondering if a CMAA could downgrade the MBP to EFI 1.6

and if so, is it fast ?

coz i don't want to leave it for a week...

if it could be done within minutes or hours, i'll drop it to the CMAA near my house

thx

 

[Hellhammer]

http://www.apple.com/downloads/macosx/apple/firmware_hardware/macbookproefifirmwareupdate16.html

 

[p3ncil]

you can't downgrade the firmware on your own.

 

[macchiato2009]

that's why i was wondering if an apple service center could do it ?

 

[macinla]

that's why i was wondering if an apple service center could do it ?

It appears they can. At least one person reports having it downgraded to 1.6 in this thread

http://discussions.apple.com/thread.jspa?messageID=10055217

 

[macchiato2009]

yeah i've read that

but i still don't know if it could be done by any Apple Service Center

 

[andothfc]

No. Some places will use the rollback, some have never heard of it and will suggest a logic board replacement, some have never heard of it and will offer no support at all.

 

[macchiato2009]

damn, logic board replacement means at least leaving my machine at least 1 week in a service center

 

[Ricky Smith]

I have followed the instructions and made sure it was formatted as a bootable USB drive however when I reboot and select the USB Drive I just get a circle with a line through it. Same result when burning to a disk. Any ideas?

 

[ptato]

I have followed the instructions and made sure it was formatted as a bootable USB drive however when I reboot and select the USB Drive I just get a circle with a line through it. Same result when burning to a disk. Any ideas?

Hi all!
I have a MacBookPro mid2009 and I'm having all this problems of freezing when watching QT videos. I've read all the threads, installed the Performance 1.0 (didn't help at all, still freezing) and tried to downgrade my computer to firmware 1.6 following the instructions posted here on MacRumors. As Ricky Smith, when I reboot my computer holding the option button with the USB drive pluged in and select the USB image, I just see a "forbidden" sign instead of the apple... what should I do? anyone has any tips?
Thanks a lot!
Pablo

 

[sydenham]

I did the firmware rollback, but it was just over a year ago. It definately works. I remember the instructions were quite specific on how to do it.Don't forget to hide the Firmware update in Software update, so someone doesn't load it my accident. Wish I could be more help.
Did you follow the EXACT instructions here?
https://forums.macrumors.com/showthread.php?p=8414998&posted=1#post8414998

 

[ptato]

Hello Sydenham, thanks for your quick answer!
I followed exactly all the instructions of that thread, and everything goes right until the very last moment, when I should see the apple and a loading grey bar... instead, I see a "forbidden" sign. Then I press any key and my computer shuts down.
Didn't find any other solution on any thread for fixing this annoying problem, so I don't know what else to do...
cheers!
Pablo.

 

[sydenham]

I would keep reading that thread as other people were having a few problems. I am sure you will get it working. I think I just used a USB memory stick to do it.

 

[ptato]

Yeah, the USB memory stick is what I used, but didn't succeed...
let's see if anyone else can help, I'll keep reading through this and other threads.
Thanks!
P.

 

[sydenham]

would it be worth a try to burn it to a cd and maybe boot from that????

 

[djeans]

Me too

Momentus xd 750 drive, can't boot, etc. trying to downgrade efi firmware but getting the forbidden sign. Anyone figure this one out yet?