My iPhone 15 Pro Max giving we water in charging port warning

If it lives 90% of the time in a fully waterproof case perhaps that's the problem. If after opening and closing the case it's possible any moisture from a humid climate could be trapped in there and condensate. If it were me living in a humid climate, I wouldn't use a waterproof case for that very reason. It's one thing to momentarily drop the phone in water then let it air dry but keeping in a sealed case is another.

pogster wrote:

If it lives 90% of the time in a fully waterproof case perhaps that's the problem. If after opening and closing the case it's possible any moisture from a humid climate could be trapped in there and condensate. If it were me living in a humid climate, I wouldn't use a waterproof case for that very reason. It's one thing to momentarily drop the phone in water then let it air dry but keeping in a sealed case is another.

I agree. Use the waterproof case when you think there is very possible, short-term risk to the iPhone such as boating, but do not keep it in there all the time.

The case is irrelevant. Why? So, if I seal humid air in the case and I take it out, isn’t it in the same humid air I sealed in the case? Apple doesn’t warranty the case. They warranty the iPhone.

Who did you talk to about service on your iPhone?

You’re welcome! Vinegar is fine for very occasional use. Vinegar is acidic and batteries are alkaline and it was a fine home remedy. Your iPhone is fine.

Happy New Year!

If vinegar restored a proper connection, the slightly acidic fluid removed surface corrosion. Surface corrosion, like moisture forms and insulating barrier, increases resistance and iPhone detected it as moisture. I can see this happening.

Moving forward, don’t use vinegar. Use something like electrical contact cleaner. Vinegar contains a high percentage of water. Use this,

https://www.walmart.com/ip/16817418?sid=c486bfb8-c000-4f65-9e2d-532691923634

It is very unlikely to void your warranty and leaves no residue. Spray solution onto a wipe or Q-tip and wipe port. Be careful of leaving any particles/lint from Q-tip.

You wrote; "I take it out every couple days to air out over night. Never seen any signs of moisture. I’ve kept almost all of my phones in the same type of case since I’m pretty much outside most of the time. First time having an issue with corrosion."

Your story has changed. Originally you said "it lives 90% of the time in a waterproof case". Taking it out of the case every couple days over night is much more than being outside of the case only 10% of the time. Apparently the person who recommended the case wasn't aware of this either. Details matter.

I also agree with Jeff where the use of vinegar is a poor choice. I'm somewhat surprised your 'repair guy' used it rather than proper electrical cleaner as found in the link.

Hopefully no permanent damage has been done. Cheers.

What store did you purchase this from?

Do you purchase Apple Care on your device?