Applies to:

• MacBook Pro (Retina, 13-inch, Early 2015)
• MacBook Pro (Retina, 15-inch, Mid 2015)

Component affected:

• Trackpad flex cable

Symptoms:

• Trackpad not working in the OS (might work in the boot menu)
• Keyboard does not work in the OS or boot menu (power button still works and may be able to perform an SMC reset)

Apple Repair program:
None

The Problem:
The trackpad flex cable just dies.
Attempts to narrow this down to a specific trace or pin has proven impossible. Every failed cable shows continuity from end to end (so it works as it should). Comparing a failed cable to a brand new one shows they are identical, every pin and trace as it should be. If it’s not a pin or trace issue, what is it? We got a tip (thanks Mike!) to not focus on continuity but check resistance instead. Indeed the resistance between the broken cables and a new cable varied a lot. On several of the pins the resistance was HALF of what it is in a new cable. This of course changes the values that current sensing circuits and clock circuits get down the line. Another possibility is the connector itself weakening and pins not connecting properly. Yet another factor is the battery this cable runs over, heat changes resistance of the traces in the cable as well and these batteries get pretty darn hot when they are charging. All in all, we don’t know exactly what the issue is but a change in resistance probably has a lot to do with it’s failure.

The fix:
Replace the trackpad flex cable. It’s an incredibly easy repair to do, the cable is very cheap and widely available. Mind you the replacement cable will likely fail again in the future but the replacement cost is so low, it’s worth repairing it whenever it fails.