sounds like a misaligned or damaged lens mechanism. When they are dropped or jarred the gears get knocked around or the mechanism breaks. When the camera trys to adjust the lens it sees resistance and cannot then throws that error

google can be very helpful in finding schematics. However, the people that have them got them from some "gray area" of the internet and often don't like to talk about it or share for liability reasons. However, it does exist and can be found with some persistence. Perhaps ask the person or group you purchased the micro soldering kit from?

looks like vacuum line going to a check valve to me. VW/audi liked to use that hard plastic tubing like is attached to the other side of that gray disc. What do each end of that go on? That would tell you as much as anything.

Typically, when doing water damage, its important to note exactly where corrosion and nastiness is before running it through the ultrasonic cleaner. This will give you a starting point for when you are in this situation. When working on a water damaged device, I often find and replace the damaged components before putting it into the ultrasonic cleaner. If you clean up the damage, you don't know where to work. if something is super crusty when it comes in, make sure it tests good before getting rid of all of your directions and clues as to what is damaged.

No, there is not. Your first indicator would be a low oil pressure light. Stay on top of oil changes, repair leaks promptly, and check your oil regularly. Keep in mind oil runs through that turbo and its quite expensive and a pain in the rear to replace.

I did mine the other day. Your BEW TDI starter should only be replaced with a quality new, not remanufactured, starter. The higher compression of the engines likes to eat cheap starters. Heres a hint, local chain parts stores don't carry the starter you need. I won't plug a site to order from but buy it from the dealership or find in the tdi forums where people recommend ordering one from. Yes, they're expensive but you won't be doing it again in 9 months. Time required is about an hour, probably less if you're comfortable under the hood. I found it was easiest to mostly work from the top side under the hood and removed the battery box and air box to get better access. Be sure you know how to get the pigtail clips loose on the VW before you start, they're different than most other manufacturers. you release the clip THEN pull instead of most others are release the clip while pulling.

sounds like a parts quality problem. if you repaired it yourself, send it back to where it came from. If it was repaired by a shop, shame them endlessly then make them re-replace it. Make sure your 3d touch is working correctly.

Well, this kind of boils me. Its aggrivating that a repair shop claiming to be professionals kept a phone for 2 weeks waiting on a part they should have had multiples on hand of and then blaming water damage because they had no idea what the problem was. As for a source for a quality battery, ifixit sells batteries and they are good batteries. finding a source that sells one at a time to consumer batteries is tough that isn't selling junk (there is ONLY junk on ebay and amazon for any price and it doesn't matter what their description says about it) Their batteries aren't $12 but they're quality. I don't really think the battery is the source of your problem though. I would think that surely this half-wit shop tried putting another battery on it before giving up 2 weeks later. I don't really think the charge port/dock cable is the source either. I suspect that what is going on is one of the capacitors or resistors immediately to the right of the battery connector on the board was knocked off in repair. You...

its not uncommon for one of two things to happen, the front camera flex is a little more delicate than others and can be damaged in the repair, ifixit sells replacements for not much money, they also often do not get plugged in straight. Open the phone back up, disconnect and reconnect the camera flex again and see if that fixes it.

It may be as simple as misaligned laser at this point. Once the sled and laser are reassembled, before putting the housing back on it, try setting the sled all the way to one end or the other. If the laser thinks its in one location but actually is in another it of course won't recognize information its seeing and possibly give this error. I don't know for certain this is your issue but it would be the next thing I'd try. Good luck with it, update as you go and we will see if anyone else pops up with some insight as well. Worst case, the disk drive is replaceable as long as the board on your existing disk drive is not damaged and can be moved to the new one. Xbox and game systems can be a lot of fun to work on.