2.3GHz, 2.6GHz, or 2.7GHz quad-core Intel Core i7 processor (Turbo Boost up to 3.7GHz) with 6MB shared L3 cache.

296 Questions View all

Boot failure / Looping chime on boot? - Logic board or EFI problem?

Hi guys,

yesterday I accidentally installed the boot-loader "Clover" on the EFI partition of my MacBook Pro (Mid 2012 - A1398).

From that point on, the Macbook booted into Clover and not my normal system. I was able to choose to boot into Recovery Mode, so I had access to the hard drive again. Then I decided to rename the folder /EFI/CLOVER/ into /EFI/CLOVER-OLD in an attempt to disable Clover.

But now i have big trouble because my Macbook won't boot anymore at all. The screen stays completely black and the keyboard does not work as well. I cannot boot into Recovery Mode nor can I reset the NVRAM or SMC, etc. The keyboard simply doesn't respond. The only thing that happens is that the startup sound ("chime") is playing constantly in a loop when i turn it on :(

So its no power issue, the Macbook is still reacting to the On/Off button but boot doesn't work.

I have already removed the SSD drive, but the issue is still there regardless of the hard drive being connected or not..

I really don't know what I can do ?

I think it is the logic board, right ? Can I repair this issue by replacing the EFI BIOS Rom Chip / EFI firmware or something like that ? Would be very grateful for your advice !

Best regards!

Answer this question I have this problem too

Is this a good question?

Score 2

Comments:

Accidentally installed? Cough-cough - Bull Sh*t!

Why?

by

Add a comment

5 Answers

Most Helpful Answer

Do you have access to a second Mac? If you do you should be able to boot up your MacBook Pro in Target Disk Mode so you can then access its drive from the second Mac that way you can undo the folder rename you did to re-able Clover boot loader. Apple T/N: Share files between two computers with target disk mode

As to disabling Clover, it doesn't appear to have an undo function within the product. I suspect you'll need to re-install the Mac EFI from Apple. Here's Apples TN on what if offers for EFI updates: About EFI and SMC firmware updates for Intel-based Mac computers. But, you'll need to first get the system running before you can even give this a try.

From my understanding Clover is really meant to be used in a Hackintosh system not a real Apple Mac system.

Reference: Clover

Was this answer helpful?

Score 4

Comments:

Thank you very much for your help!

Unfortunately no access to a second Mac. But I ordered a SATA adapter that is compatible to my Macbook SSD in order to backup my data from the SSD just in case... So I will soon be able to rename the folder.

What I don't understand however is that the problem (boot chime loop) still occurs even if there is no SSD or other HDD connected to the Macbook. I have tried this by removing the SSD.

So do you really believe the system will work again after renaming the Clover folder ?

I am a bit scared that I bricked the internal EFI or BIOS - or is this unlikely ?

Thanks a a lot :-)

by

Don't think thats going to help you here.

Clover EFI is redirecting the load from the firmware to the file boot loader within this folder. So swapping out the drive will end up doing the same thing.

You'll need to find a second Mac to either do the Target DiskMode method or to alter the file using the SATA to USB adapter/external HD case to hold your drive from the second Mac.

The EFI (BIOS) has been altered by Clover. It placed a hook to force the boot from the file within the drive which is why you'll need to undo it by reloading the EFI from Apple.

by

The problem is that I don't know if Target DiskMode will work, because the keyboard of my Macbook doesn't seem to respond except for the on/off button.

At least resetting NVRAM, SMC and Recovery Mode do not work. It seems like the system is occupied with the startup loop.

I will rename the folder soon and let you know if that fixed my issue.

Should I also install this EFI Bios update ?

Here : https://support.apple.com/en-us/HT201518 ?

by

See if you can find a USB keyboard that might give you access to the needed keys.

You'll need to apply the update to over-ride Clover unless you want to use it. Then just be careful not to alter the folder and contents.

by

Add a comment

I have the exact same issue.

Unfortunately booting into target mode from another MacBook doesn't work for me. Neither by remote keyboard.

Where you able to fix without manually pulling and reprogramming the EFI chip?

Really don't want to go there if I don't have to....

Any help would be appreciated!

Was this answer helpful?

Score 0
Add a comment

Rule out display issues

Findout on VERIFIED SOLUTIONS

Was this answer helpful?

Score 0
Add a comment

hi alex s. ,

i have the same issue. i messed up my macbook because of clover. do have a solution already?

Was this answer helpful?

Score 0

Comments:

Hi Jose,

I had to get a new MacBook Pro. Apple's Tech Support couldn't (or didn't want to) fix it. It's probably an issue they see very rarely and the aren't into BIOS chip soldering. They only try to replace broken parts.

Strangely, according to the technicians, the MBP booted up correctly without issues when the screen was disconnected - but replacing screens didn't help. No clue why..

I think it's an EFI BIOS chip issue. You may be able to fix it if you get a new Bios Chip soldered onto your Mainboard. But not sure if that will fix it, might try that sometime in the future.

Alternatively, trying to reflash the BIOS with default firmware might do the trick as well. But for me it didn't really work.

Best regards,

Alex

by

Add a comment

Hi all, someone found a solution ? I have exactly the same problem ...

Was this answer helpful?

Score 0
Add a comment

Add your answer

Alex S. will be eternally grateful.
View Statistics:

Past 24 Hours: 6

Past 7 Days: 32

Past 30 Days: 60

All Time: 261