Hi.
I received this iPhone 6s from a customer with chlorine water damage. The damage was fairly severe. The phone initially had a partial short on vcc main and would not power on.
When I hooked it up to the DCPS it drew very low amps without being prompted to boot. I removed shields and cleaned with an ultrasonic cleaner. I then touched up a lot of components that had corrosion. I replaced the few components that I found to be missing.
After cleaning and touching up, the board completely booted and the screen lit up and showed the apple logo. After a few seconds the screen went dark. I looked at the screen under light and found that the phone still had image and completely booted to the passcode screen. At that point I realized the board was getting quite hot and found that the phone now had a full short on VCC main but would still boot all the way to the passcode screen and had no backlight.
I eventually found the short to be in or under U4020. After removing U4020 I connected the board to iTunes and I downloaded data for the customer.
I then replaced U4020 IC with replacement from donor board and I was expecting a functioning phone with backlight but after replacing the IC the phone did not boot.
It now starts as if it will boot and current goes to about .6 to .7 amps but then drops back close to zero and continues that cycle but does not boot.
Can anyone help? I am really just learning motherboard repair and I am somewhat stuck. i have begun to check readings between known good board and this damaged board and I have found some significant inconsistencies but I don't know how to interepret them or where to go next. All of the inconsisitent readings seem to involve a circuit that is tied into U4020. Did I likely damage the IC at some point??? I had to remove the underfill stuck to U4020 and I was very careful and took a very long time but I had a hard time with it.
Thank you in advance! I promise to give back to this board one day once I have the knowledge and requisite experience! It has already helped me so much!
I received this iPhone 6s from a customer with chlorine water damage. The damage was fairly severe. The phone initially had a partial short on vcc main and would not power on.
When I hooked it up to the DCPS it drew very low amps without being prompted to boot. I removed shields and cleaned with an ultrasonic cleaner. I then touched up a lot of components that had corrosion. I replaced the few components that I found to be missing.
After cleaning and touching up, the board completely booted and the screen lit up and showed the apple logo. After a few seconds the screen went dark. I looked at the screen under light and found that the phone still had image and completely booted to the passcode screen. At that point I realized the board was getting quite hot and found that the phone now had a full short on VCC main but would still boot all the way to the passcode screen and had no backlight.
I eventually found the short to be in or under U4020. After removing U4020 I connected the board to iTunes and I downloaded data for the customer.
I then replaced U4020 IC with replacement from donor board and I was expecting a functioning phone with backlight but after replacing the IC the phone did not boot.
It now starts as if it will boot and current goes to about .6 to .7 amps but then drops back close to zero and continues that cycle but does not boot.
Can anyone help? I am really just learning motherboard repair and I am somewhat stuck. i have begun to check readings between known good board and this damaged board and I have found some significant inconsistencies but I don't know how to interepret them or where to go next. All of the inconsisitent readings seem to involve a circuit that is tied into U4020. Did I likely damage the IC at some point??? I had to remove the underfill stuck to U4020 and I was very careful and took a very long time but I had a hard time with it.
Thank you in advance! I promise to give back to this board one day once I have the knowledge and requisite experience! It has already helped me so much!
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