MacBook Pro 13″ Late 2011 A1278 820-2936

Procurement

I picked this one up on eBay for $203. It was described as “Laptop doesn’t stay powered on/boot fails”. It came with RAM, hard drive and charger, so it was a nice, complete item. When it arrived, it had a missing foot on the bottom, but everything else matched the eBay description.

Symptoms

I plugged in my charger which instantly showed a green light, that then changed to an orange light to indicate that it was charging. That automatically shows me that my PP3V42_G3H power rail is present. Next the fan started spinning, the computer chimed and the LCD backlight came on. Time to see if it boots into an operating sys… what the f***? Is someone trying to take this piss? The MacBook starts booting into Windows!

Windoze!

I’m guessing that the seller just dropped in a hard drive that was lying around, and it was pre-loaded with Windows 10. Strangely enough, it loaded all the way to the login screen, then I decided to put an end to the madness and shut it down. That’ll be the last time that operating system gets loaded onto this little Mac.

 

What’s Inside?

At a glance, not too bad.

A little dusty inside, but not too bad. I whipped out the logic board, pulled off the heatsink then had a bit of a browse around under the microscope. Some of the test pads under the dust had a distinct greenish hue, but a quick ultrasonic clean will set those right.

Video

Corrosion

Some nasty corrosion, very close to the CPU.

As I got to the top right of the CPU, I noticed a little clump of corrosion. R4999 popped off the board with the gentlest of touches from the tweezers. This little group of capacitors and resistors — so close to the SMC and GPU — could definitely be the cause of the unexpected shut downs described by the previous owner.

Component removal

I knew this little cluster of components would need to be replaced, the main concern was whether the pads on the logic board would be too far gone for me to clean. I wrapped the GPU in some aluminium foil to protect it from the hot air, then plucked off 8 or 9 resistors and capacitors. I then attempted to clean up the corroded pads. During this process, a large part of the board coating lifted off, resulting in one huge pad, rather than two little ones. They were all joined together, so the issue was only aesthetic in nature. Most of them came back to life straight away, but a couple of them needed some extra persuading. One of the pads had lifted off, and I was now looking at a different layer of the board. I needed to stop and check whether I was still soldering to the right place, or if I was in the process of creating a short circuit!

I had to do a bit of scraping with the scalpel to expose some clean copper, but I was able to create enough area for all of the replacement components to attach to the board in the correct way. It wasn’t going to look pretty, but it would be secure and functional.

Component replacement

The recipient and the donor.

Thankfully I have a couple of donor boards for this model, so I was ready to go. There was quite a bit of work getting all of the components back in place, especially with the manky pads I had to create, but I enjoyed every second of it. After some pushing and prodding, all of the components came to rest where they needed to be.

Video

Testing

It’s a bit hard to test something you know already works. I’d already seen it boot, so there was no real joy seeing it boot again after my repairs. It was now just a matter of putting it through its paces to make sure it was reliable. After some basic testing, I cleaned the board in the ultrasonic, gave it an alcohol bath and then dried it in the oven. I placed some conformal coating over the repaired area, reattached the heatsinks and then put it all back together.

The finished repair.

I ran my usual suite of tests: I ran the Apple ASD tests (which returned a clean bill of health), I checked the hard drive, RAM, USB ports, SD card reader, Thunderbolt port, Firewire, DVD drive, keyboard, trackpad, camera Bluetooth, Ethernet, WiFi, microphone, speakers and audio port. So far, so good. I then ran a swathe of operational tests to check the CPU and GPU.

Sale

Squeaky clean and ready for sale.

This computer came with only 2Gb of RAM, so I put in another 2GB, as well as one replacement rubber foot. I listed the MacBook on eBay for a 3 day sale, and received a very disappointing price. Lots of watchers and lots of bidding, but it didn’t get the same result as many of my other auctions. I’ve paid more for broken MacBooks than the final sale price of this fully functional and refurbished MacBook.

It’s the first 3 day sale I’ve ever done, and it’s also the first sale I’ve done where the auction period didn’t include a weekend. I’ve found that people often do silly bidding on Friday and Saturday nights, so this may well have been the undoing of this auction. I have no regrets though, as I really enjoyed the repair, and the sale was a good learning experience. I still made a modest profit, so c’est la vie.