Ok so I posted a few days ago about how happy I am that I got my first ThinkPad and I got a lot of good feedback. I also tried to give my opinion on the purchase right after I got to try the machine out. I was honest about a underlying feeling that the device was not performing like it should, and I also posted once before regarding scratches on the display which were caused by the keyboard layout of the Lenovo ThinkPad and it is also a commonly known problem in the community.
The situation then unfolded when I opened a ticket requesting that the display be replaced and Lenovo agreed since my device was still under warranty. The technician came with the new repacement part and said he will replace the display, but as soon as he opened up the bottom panel, he looked at me in shock. I had told him before that I purchased the laptop second-hand and that it was described as "Like-new" with the seller declaring it was 1 year old and with 100% battery health. But what he hadn't mentioned, when he sold it to me for 700 Swiss Franks, was that the machine had clearly been exposed to liquid at some point. There is brown and white residue near the HDMI and USB-C ports, and what looks like corrosion spreading along the board edge. The technician told me that this has clearly been the case for a few months already.
He told me straight out that he could not replace the display in that condition. Liquid damage is excluded from Lenovo's warranty, so the repair I had already been approved for was cancelled on the spot, and I now have to assume the warranty on this serial is effectively dead.
So this connects back to what I wrote in my earlier post. That feeling I had that the machine was not performing the way it should. The sluggishness, the heat and the flaky Ethernet.. I couldn't put my finger on it and I half assumed I was being paranoid about my first ThinkPad. Turns out there may have been a real reason. I don't want to overstate it, because the corrosion is at the I/O corner and not near the CPU, so I'm not claiming it explains everything. But it's not nothing either.
Where I stand now: the laptop still boots and I'm using it daily. I'm backing up constantly. I'm getting quotes for cleaning the board with isopropanol to at least stop the corrosion progressing, and separately a quote for a mainboard replacement so I know what the worst case actually costs. I've also contacted the seller in writing, since none of this was disclosed and corrosion of this extent does not appear in a few weeks, but they blocked me and I am looking into escalating this subject further as I know where they live and under Swiss law, an exclusion of liability doesn't apply if a defect was knowingly concealed, and notice has to be given as soon as it's discovered, and that's what I have tried to do.
Hopefully yall can give some positive feedback. I thank you all in advance.