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water damaged Dell XPS 13 laptop and now wireless wifi failure
First, most laptops provide wifi through one of 2 methods: a miniPCI/miniPCIe card inserted into the computer, or as an integrated part of the motherboard.
If you have a wifi usb adapter, try using that. You should be able to get wifi working on that.
From a bit of research it seems like the dell xps 13 uses a wifi card instead of the integrated wifi chip. Open up the bottom of the computer and look around. You should have easy access to the hard drive and ram, but there might be another removable module (the wifi card) that looks like a small removable circuit board, similar to RAM modules, except a different shape/size.
You could try replacing that and seeing if that gets you anywhere, but honestly because this is water damage, and the wifi card is usually accessible on the bottom of the laptop, I think you'll find replacing the wifi card may be pointless. Motherboard damage in the right place could render a perfectly good wifi card useless if you damaged it just right.
Your best bet is to get a usb wifi adapter.
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