@KingCornWallis — I suss you’ve probably given a thorough System Management Controller (SMC) reset a try if you’ve also tried running the Blank Board Serializer (BBS), but in the event you haven’t just yet, here’s Apple’s archive-dot-org
archive page for handling the unibody MBPs such as yours. Process of elimination and all.
The SMC reset steps (for the sake of future readers) for unibody, post-2008 to mid-2012 models:
- Shut down the computer.
- Plug in the MagSafe power adapter to a power source, connecting it to the Mac if its not already connected.
- On the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time.
- Release all the keys and the power button at the same time.
- Press the power button to turn on the computer.
Note: The LED on the MagSafe power adapter may change states or temporarily turn off when you reset the SMC.
The BBS, at minimum for consumer Intel Macs,
should permit a re-flashing of the SPI ROM chip which holds the serial number (unlike, as I understand it, a one-time, write-once/read-many shot for PowerPC-based boards, which use a different EPROM).
From the sound of the issues you faced before resolving most of them, there may have been an event, however unlikely, which corrupted data on that SPI ROM. An SMC reset ought to clear everything which, routinely, would have been saved in the past by a PRAM battery (unibody and later MBPs lacked these). With a reset SMC, this can at least eliminate anything stored in system parameters which might interfere with booting into and running the BBS utility.
Last bit: a tool like the one you pointed to on the ebay is probably not worth the cost, especially if you only had plans to try this on one board alone, and you aren’t, say, at an electronics recycler salvaging serviceable boards, in quantity, which can continue to be used as replacement parts in other Macs. Heck, for the price they charge for that device (which is just a tidy, but spendy way to do SPI ROM programming), you could probably pick up three or four mid-2012 MBPs in outstanding shape!
If it's more than a few years old and out-of-warranty, a very simplistic question:
What does it matter whether or not the Mac can identify itself with a serial number?
It probably doesn’t. But that really isn’t the point, nor is it the point of the question he was asking.
I have owned two Macs which arrived with no serial at all. Neither was in warranty or within the scope of AppleCare when I bought them. Both — a late 2005 PowerBook G4 and an early 2008 MacBook Pro 17 — had had Apple-authorized board replacements completed earlier in their lives (both with the green dot on the RAM bridge, though I’m only clear
why the 2008 model had its board replaced).
Nevertheless, at least with the former, I went ahead, booted into the BBS utility and re-serialized the new board to sport the (interest, at least to me) serial on the manufacturing plate, despite the fact the board itself was manufactured several weeks after the laptop was assembled on “week 53” (literally, 26–31 December 2005).
Why did I do this? Because a)
I wanted to and b) I wanted to learn from the experience. If there had been a c) a resolution to some of my system’s particular quirks (or restoring a past corruption to its original SPI/EPROM data), then that would have also been another reason for trying the BBS.
The other, my early 2008 MBP, still has not had BBS applied because I am le tired, I need le nap, and I plan to fire ze missiles later.
In ARD, that same Mac reports as the following:
“12345678”. That never ceases to amuse me.
From the original poster’s vantage, he is trying to troubleshoot a technical issue. Your response was not instructive.
It either works...
or...
It doesn't work.
Correct. And that was what he sought to verify with the community.
It is, additionally, possible he has long-term plans to sell it to someone who’s particular about the serial reported by the system matching what appears physically on the case itself (the logic board serial should be slightly different, as it is serial-labelled as a component, not as the whole system). That’s, equally, a valid reason.
Whatever the case, a serial vanishing on the original board is unusual, and I look forward to reading more of
@KingCornWallis ’s troubleshooting steps as they unfold.
