Chosen Solution
Hello good people! So far this site has just about got my out of the woods after almost losing my Macbook. Let’s just say my cat urinated on the keyboard.. And killed it. I disconnected everything, took all the internals out and cleaned with rubbing alcohol. Let the battery stay unplugged for a few days to let die whatever bad charge was in the system. Turned it on and hurray it is alive. (Thought I’d condense this and not include the hours of frustration and ripping my hair out.) When it powered up all was well except the keyboard didn’t work at all. So I cleaned the zif connector due to possible but unseen corrosion and now the keyboard is alive. My problem is that everything I type now shows up on the Mac as some weird characters like this: ```££ I turned on the keyboard viewer to see what that Mac was interpreting and when I press a button the correct one does show up on the viewer.. Weird! I’m thinking it is due to a stuck ALT key. The weirder thing is that when I click on a letter in the viewer such as A to use the viewer to type.. The weird character is still showing up and it does not show the alt key as being pressed down. I’m stumped! Is this a software issue that can be fixed? Or hardware due to what happened? I checked the language and keyboards and such and the only thing selected is United States. Thanks for any possible help!
I think the keyboards wiring is messed up by your pets accident. You can try using an external keyboard (USB) to prove if it’s a software thing (I doubt it). I think its time to replace the upper case assembly. Follow this IFIXIT guide: MacBook Pro 13" Unibody Mid 2010 Upper Case Replacement. A used part is around $140 US. The problem you face here is the corrosive effects of the cats urine as over time it will slowly eat though the copper traces of the keyboard switch pad. I’m sure you didn’t take the whole keyboard apart here (50 some odd screws or rivets).
The acid and liquid in cat urine may still be causing damage. Not just that: There are sugars in urine that can scorch if enough heat develops, burning the electrical traces. If the USB ports are also wonky, you may have more serious logic board issues. At this point, if you’re still trying to use this damaged computer, you’re just trying to get around the problem rather than tackling it head-on. I’d suggest stripping the computer down again, and then washing all the circuit boards in anhydrous (i.e., water-free) isopropyl alcohol. It’s available from electronics stores and specifically intended for cleaning circuit boards. Not rubbing alcohol, which is 50% water. I use a Tupperware-like plastic tub to make a bath, and then dunk all the stripped boards in that bath for a day or so. I keep a soft, dry toothbrush around to gently scrub the affected areas free of all debris; you’ll want to include the peripheral sockets and the top case socket in that treatment. This guide gives some general guidelines for washing and drying before reassembly: Electronics Water Damage
