Component Level Mac Repair

So it became apparent that some members on here are interested in the world of computer repairs that go beyond the realm of swapping out entire modules. I know I am. I started teaching myself the intricate circuits that comprise modern Logic Boards earlier this year and successfully repaired my first board soon after; a MacBook Pro with a shorted filter capacitor on the nVidia MCP chipset 1.05v supply rail. That was soon followed by a MacBook Pro 13" Retina 2014 with water damage that caused a capacitor to short to ground on the main PPVRTC_G3H line that powers the various onboard and CPU clocks, which was also repaired and returned to service.

Make no mistake, I’m still a novice at board repair. But I find it fascinating knowing how the electrons fire around the complex circuits of our computers to generate the images and sounds that allow them to deliver information to us in a form we can understand. I owe a lot to Louis Rossmann of the Rossmann Group, NYC for his extensive video series on board repair. Board repair seemed like a difficult, almost impossible task at first but after watching these videos, I started to think “I can probably do that…” and decided to dive in.

Anyhow, I’m creating this thread so I can stop hijacking the DIY Repairs thread once and for all. Besides, I think this has somewhat moved beyond the scope of the average DIY repair.


Currently working a machine for another AppleTalk member. It has no backlight and the battery is not detected. Starting with the backlight, I tested across the backlight fuse and found it open circuit. Checked for a short to ground on PPVOUT_S0_LCDBLKT and it came back all clear with 0.597 between this rail and ground in Diode Test mode. The LCD also tested fine when connected to another board. Confident there was no short to ground, I temporarily hooked my tweezers to each side of the fuse.

Bingo. Backlight restored. This board needs a new fuse. (Pictured in the centre of the photo with a white dot on it.)

Once I find a reliable source for replacement fuses, all going well I should be able to return this board to service. Almost anything can happen when repairing a board of course so I won’t declare victory yet. As I continue working on it I’ll post updates.

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Nice work mate, interested reader here on your progress.

This machine went through the works. The backlight fuse was replaced, the battery replaced, the body aligned and cleaned and detailed inside and out.

The backlight issue we already know, but during testing it became apparent the battery was also completely dead and wasn’t detected. I sourced some batteries recently that work fine, but have high cycles, and one of those was certainly better than the completely dead one in the machine.

A realigned display and tightened up trackpad later, along with a clean and detail inside and out, and another machine comes back to life.

I very much enjoyed learning how to solder in year 10… But that was 1993, and whilst I did pick up a soldering iron years ago, its rarely seen use… I don’t think I’ve really quite got the dexterity to do these kinds of repairs, though I certainly take my hat off to those that can!