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The Capacitor “issue” he repeatedly claim exists. If there were such a huge problem, thousands of people would be claiming their MacBook Pro’s would be failing to boot due to a slightly undersized capacitor. They simply are not. It is a seldom mentioned problem, most likely due to a capacitor that is way below specs that is expected in production of capacitors. You do not over engineer parts that require more space/weight/cost due to a 1 in 1,000,000 potential failure rate of a minor part. Occasionally, a run of below spec parts may get through. However, every part that takes more power to run, also requires more battery power to support it. Capacitors fall into this category. They need to be charged up to provide the voltage this guy says they need to do their job. That power has to come from somewhere. Engineering decisions which he says he can do better than Apple.

I don't believe the issue that he raises has anything to do with the capacitance value of the part. He states that when the issue is seen, the voltage across the capacitor has dropped to 0.3 volts rather than the normal 1.052 volts. This is a clear indication that the capacitor in question has failed, and is displaying excessive leakage current. He mentions using a replacement that is physically larger. Though he doesn't so state, it sounds like he is using a replacement with a higher voltage rating.

It's hardly a "minor part" if its failure results in a totally inoperative unit.

Capacitor manufacturers generally recommend operating tantalum capacitors at no more that 50% of the rated voltage for optimum reliability and longevity. Apple's choice of a 2 volt rated part would be marginal from this standpoint. A 2.5 or 3 volt part would have been a better choice, albeit at a slightly higher cost.

It sounds like he is adding in a safety factor which is prudent as long as the larger part will fit.

It sounds like he is adding in a safety factor which is prudent as long as the larger part will fit.

My point is that the small number of failures of those capacitors indicates that Apple’s engineering decision is the right one. Just because he has run into a few, less than 1/100 of 1% of the total production run, with failed capacitors which he can repair at the board level (which is uneconomical for Apple to do) is meaningless.