-3403D error

I have it too. Using an old (around 2010) and now problematic iMac.

https://support.apple.com/en-us/HT201257

I think in my case, and maybe yours too, this paragraph pertains:

If you're using OS X Lion v10.7 or earlier and you can't get AHT to start, see if you have an OS X installation disc named “Applications Install Disc 2.” Insert the disc in your internal optical drive or external Apple SuperDrive before following the steps above. Or, if you're using a MacBook Air (Late 2010), plug the MacBook Air Software Reinstall thumb drive into your USB port instead.

The problem with my iMac is that the internal optical drive broke very early after purchasing this iMac. Actually it broke in (or around) an earthquake back in 2011 :-P It just won't swallow any optical disc since.

2010 and older Mac's that run Snow Leopard or older. Have to use the install disk for AHT. Some 2011 or newer with a smc and efi update can run the online diagnostics. Usually the update is part of a software update. If you have the original install disks, you don't need internet diagnostics. This is because after Snow Leopard, all operating systems came by way of a download from apple, if not preinstalled. The reinstall and the utilities is on line. The early 2011 that came with Snow Leopard generally can't use the online diagnostics. As a general rule. If your computer came with Lion or newer, you use the online diagnostics.

Hi,

I'm having exactly the same issue with a late 2010 27 inch iMac right now.

EFI firmware is up to to date.

Any clues?

Thanks!

Having the same exact issue!

Same thing, 2 days without a solution !! grrr

Same thing, mid-2010 Macbook Pro I just upgraded to Yosemite yesterday. Everything else seems to work fine but I need to do a hardware test and can't.

Try booting the MBP with the OPTION+D keys. It may work.

If you had the original install DVDs, you would not have this problem. Duplicates can be obtained from Apple Customer service.

Ciao.

Doesn't work. That's where the error message comes from. Pressing D only works if you have the install DVD in the drive, Option + D loads Internet Recovery and is supposed to work as long as you're connected to a network. Using this option is what's causing said error message.

Same here... would like to run a memory test, with no dvd available.

So used OPTION + D, connected to my wifi... after a few seconds this error appears.

Macbook Pro / 12-2010

I'm getting the same error with my 13in Macbook Pro Mid-2010 running Yosemite 10.10.2. I haven't been able to find any fixes online. Anyone have any ideas?

MY MBP was working very well with yosemite (mid 2010 build) until it 'updated' last week. Now I can't even use it without it crashing!! I'm so annoyed. I get the impression that the newer the software & the older the machine, the less likely these two will cooperate together! Are there any clever techies out there who can help diagnose the problem before I wipe the hard drive & re-install from a back up? I'm only glad I have an iPad to use while I'm stuck with this problem! 😠

same error for me on macbook pro 17" 2010

Same error on MacBook Pro 13 inch Mid 2010.

I've tried Apple Chat but they have no knowledge about error codes like 3403D.

Is there any Genius out there who can simply explain this code?

The same issue. iMac 27 2010