Minho

Alright, seeing as how I am always answering questions here, I thought I'd reverse the roles here for a bit of fun. I have an...

Hello Mac Experts (@mayer, @danj , @reecee and others) I have an iMac 27", Late 2012 that is not booting properly. It is usua...

This iPad has a dead zone on the left edge of the digitizer, about 5 mm from the edge. I proceeded to do a standard digitizer...

Hello Mac Guru's (talking to you @mayer, @danj, @reecee)! I have another MacBook Air A1466, this one an early 2015. The SSD a...

Hi everyone. This is a follow-up to my MacBook Air 13” (2014) – Water Damage, will not power on. Thanks to everyone who repli...

Hi everyone. I have a water damaged (tea) MacBook Air that was dead as a doorknob. No light on the MagSafe, no fan or anythin...

If a new battery and charge port still don't resolve the issue, then you either have faulty replacement parts (possible) or a logic board issue. There is an IC (commonly referred to as Tristar) responsible for communicating with the charging device and uncertified chargers can damage it. Unplug the battery and connect a known-good (preferably Apple original or MFi) charger to the phone. A properly working phone will show an Apple logo and boot loop. If the Tristar IC is bad then the phone will not do anything.

It’s unfortunate that you don’t remember or understood what the shop told you because it was certainly important. If you feel like you are being bamboozled, ask them to explain it again…it’s usually important. Yes, you can replace the charge port but based on the history of the device and the symptoms it exhibits, I would suspect something may be wrong with the charge circuit on the logic board. Of course, the first step in diagnosing this correctly is to try a replacement charge port. If you do it yourself, you will have to buy the part upfront. Another option is to find a reputable shop that does micro-soldering as they will be able to dig a little deeper.

The battery is certainly at the end of it’s useful life. 80% is more or less the cutoff point between a normal battery and a degraded battery. On iPhones, they continue to work well down to about 70% and anything below that can go either way; working but just for less time or in some cases, start doing that “shutdown” on full charge thing.

Apple does have a tendency to route traces around screw holes…but not in this particular instance. That said, there are a lot of very fine traces in close proximity to the screw hole so if any one of those is compromised, then you will have issues with your logic board. Each colour represents a different internal layer of the PCB. You will not be able to see these with your naked eye when looking “from the side”, only when looking at traces from a top perspective. I would take a closer look with a microscope to see if any the adjacent traces are visible, otherwise, you will probably not be able to repair this logic board.

With water damage, you have to decontaminate the logic board before doing anything else, otherwise there will be latent issues down the road. Not every water-damaged phone is recoverable and depending on the kind of liquid (salty, dirty, filthy), sometimes the success rate is quite low. That said, IMHO, it's always worth a try otherwise we are just piling up the e-waste. The proper way treat a wet phone is to do the following: (1) Open your phone and remove the logic board (follow this guide) (2) Inspect the logic board, especially around the connectors and look for corrosion. (3) Inspect both sides of the board. Unfortunately, most of the board is covered in shields. That's usually where the damage is occurring. (4) Put your board in a container with >90% isopropyl alcohol and let it sit for a while. (5) Use a soft brush, like a toothbrush and lightly brush away any corrosion you see. (6) Rinse in alcohol and repeat. (7) Let it air dry for a day. (8) Re-assemble and hope for the best. A professional repair s...

If you brought your phone to the Apple Store, I would return there and have them fix it under warranty. Keep in mind that they may just elect to give you a replacement device so make a backup before you go.

Do a thorough visual inspection, preferably with magnification, of the area surrounding the battery connector. There are several tiny SMD components just above the connector. Of particular importance is FL2400, hghlighted in red. If it is missing (which can happen when you pry the connector off), then the battery state does not get communicated to the CPU and this can also cause charging issues and fluctuating readings. This can be repaired via a micro-soldering repair.

It sounds like the charing circuit may have been damaged because the phone works when you have a fully charged battery installed. Was the charger you owned or replaced it with an Apple original? Low quality chargers can damage the charge circuit. You could try a new charge port but IMO you have a logic board issue. This can be repaired but you will need to find a shop that does micro-soldering repairs.

The iPhone 7/8 series have a very inconvenient bend on the Home Button flex. It’s really easy to tear the flex, either near the logic board connector or at the 90 degree bend before it sneaks underneath the LCD heat shield. You have to be careful when you lift the screen off the first time but also anytime the flexes are connected and you have the device open. You will need to carefully inspect the flex to see if there is any damage. Magnification here will help.  Look for tears to the flex or any physical signs of damage. You should also check the connector to insure none of the pins are damage or that there isn’t any debris.

You definitely need to get Q3201 installed properly. There is no schematic for the iPhone 8 available but the iPhone 8 Plus works fine for most of the “compute” sections of the phone. The battery SWI/HDQ communication configuration is the same electrically speaking between both devices so you just need to apply the wiring logic from the 8P to the 8 (via ZXW).