First important detail was the customer had a really cheap aftermarket power adapter and questionable USB-C cable, machine gets no power and doesn’t charge, USB-C amp meter confirms this, tested with another power adapter, faults the same but my test USB-C adapter gets stuck on 15v instead of negotiating like 19v-20v from the charger that it shouldt. The customers adapter gets stuck on 4 or 5v with no current at all, open the machine and the CD3215 is getting red hot because it has an internal short, USB-C port on side of laptop has no damaged.
replacement chip arrived, replaced it, CD3215 no longer gets red hot but both power adapters still fault the same on their own and no power at all if I try with the USB-C amp meter, I wasted a lot of time assuming there must be something else wrong with the board or the first replacement CD3215 was not shorted like the original but maybe faulty in another way.
Turns out the laptop was fixed but it was the only thing that was working, my test USB-C power adapter was faulty, also the customers dodgy USB-C power adapter faulty, customers USB-C cable straight up looked cursed so I didn’t even entertain using it, and my USB-C amp meter was completely non-functional. CD3215 is a common chip to fail and is used on multiple apple models.
Be super careful with USB-C, use good quality power adapters and cables and hopefully avoid fun situations like this, also when assessing something have a good look at the USB-C ports under a microscope and shine some light down into the socket so you can see if there are any bent or damaged or missing pins.
Also with replacing the chip it’s well worth covering everything around the chip with high temp kapton tape or teflon tape or aluminium foil or all three and just have the chip itself exposed for removal, it is really easy to blow one of those little resistors out of place when removing the chip or bump them when removing the excess solder from the pads on the board so just be really really careful.
so in summary USE GOOD USB-C POWER ADAPTERS AND CABLES I don’t have a recommendation for cables at the moment because low quality but over priced cables on ebay and amazon etc. and on sale at fuel stations is a real problem. But as for power adapters I would recommend Targus USB-C power adapters, the 45W one I got works well, compatible with any real USB-C powered device regardless of brand, samsung, apple etc. you’ll pay between $70-$100 for one but they are a decent quality product and when you consider the $20-$30 dirty cheap adapters might damage anything plugged into them it’s really really well worth spending the extra on good power supplies.
https://au.targus.com/collections/power-adapters/products/45w-usb-c-power-adapter
Note about CD3215C00: The datasheet for this chip is not available and a faulty chip won’t always be obviously shorted to ground and getting really hot, for more advanced troubleshooting when you think you might have a CD3215 that is quietly faulty then the information in the community wiki that old man Rossmanns Repair started is probably your best bet, there is some information about cross compatibility or lack of cross compatibility with different boards that use different versions of the CD3215’s https://logi.wiki/index.php/CD3215_Bootup_Sequence