Guy Burns wrote:
1. The MacBook Pro is a 13" non-touchbar.
Ouch, I was afraid of that. While all of the 2017 models had issues, this one had all their issues, plus even some more with the SSD, Battery, and having theUSB-C ports integrated into the Logic Board. Unfortunately there is no way to know if this laptop was one which had the bad battery. Apple never released specific details on what system serial number ranges were impacted by the battery issue. Apple only had the user check their system serial number to see if it may have been within that range. Unfortunately that free repair program has expired so that Apple article & check no longer exist.
3. Battery level is showing at 100%. The laptop was only used about 20 times a year for a few hours each time to show images at the club, always with power connected.
That type of use could easily have caused damage to the battery. If the previous owner let the battery drain to zero while it was being stored/unused, then that will easily damage the battery.
Ques
Is it possible that third party software can cause startup to not work? With all this "signed" stuff for the protected operating system, I don't understand how that can happen.
I doubt third party software would cause a power on issue, although there is a small possibility if it modified a PRAM setting it could somehow cause a problem. A boot issue yes, power on issue probably not.
The signed software & known developers gives people a false sense of security in that it makes it seem the developers are doing a good job programming & not doing anything nefarious. That isn't really true. The signed aspect just means that the app is just how the developer made it (either good or bad) and by the time you install it the app is still the same. Plus if you don't get any notices while launching the app, it means the app hasn't been modified while it has been on your system.
I think it takes a lot to have a developer lose their status as a "known developer" allowed to sign & distribute their software by Apple or to release it in the App Store.
A hardware issue of some sort seems the most likely, but testing with a clean install is the best way to confirm. Figuring out which part of the hardware is causing a problem is another matter. The Battery is a definite possibility due to its age & how the laptop was only intermittently used. Plus knowing that some of those systems had a known issue with the battery makes it even more likely.
Other possible hardware issues:
Bad USB-C ports. Because these ports have dual use for data transfers & supplying power to the laptop, they tend to be more susceptible to hardware failures due to faulty external devices. Plus I find these USB-C ports tend to attract a lot of accidental liquid damage. It only takes one small drop of liquid to enter the port to damage it so even just a splash of liquid from a couple feet away could possibly make it inside the port. I see this so often, that I always examine these ports first even if the client doesn't mention any issues. Unfortunately an external examination by looking into the port is not enough to be 100% sure the contacts are clean & healthy.
Bad Logic Board. Sometimes people connect cheap devices and these can damage the USB & power controller on the Logic Board. Each port has their own chips. However, due to how Apple wired these circuits, sometimes if one port is damaged, it will affect the other ports as well. Liquid damage to the Logic Board is another possibility since there is nothing preventing liquid spilt/splashed on the keyboard from seeping through & onto the Logic Board.
In my previous post I mentioned I suspect a hardware issue with all of these Apple USB-C Intel Logic Boards. In fact many times just performing an SMC Reset will stop the laptop from powering on. I've had to connect & disconnect the power adapter to try to trigger an auto power on, while other times I had to disconnect the battery in order to reset the system to allow it to power on again. However, I've never seen a laptop with chronic power on issues, just intermittent ones.
The battery on these Intel USB-C model laptops have two connections to the Logic Board. One is a large screw and another is a flex cable. The flex cable slides into a connector on the Logic Board with a very fragile locking lever to hold the cable in place. Some models have another connector on the battery board as well. It is possible that one of these connections could have caused the flex cable to get out of position. This latching lever is extremely delicate and very easily damaged even when being careful. Many times just closing the latching lever can cause it to twist & slide off the connector....reinstalling it is nearly impossible if the lever comes apart from the connector.
