Chosen Solution
Hey everyone, I’m new to the iPhone logic board repair scene and have bought a liquid damaged 5S which doesn’t power on, just wanted to see if I could get it to come on. I have removed the logic board which is heavily corroded, I ultrasonic cleaned it and connected it up to a DC power supply with 3.8V, it was drawing a small amount of amps, approx. 0.3amps. I found that there was continuity between live and ground on a VCC Main cap, I then used freeze spray and discovered the U3 chip headed up instantly. I removed this chip and the short on VCC Main was gone. I then connected the power supply up again and found it still had a short. I tested a couple of caps and found that live and ground cap was shorting on the U10 chip, removed the chip and the short has now gone. When I plug the power supply on and supply 3.8v it now draws 0amps. When I push the on button the amps range between 0.2 to 0 constantly. There is also a very small red light that flashes to the left of the earpiece. I am using the original parts and screen to test. Could anyone give me an insight as to what would cause this? This is just practice to see if I can get it to boot up. Could it be the PMIC at fault? Thanks
Very small red light sounds like proximity sensor is going off for some reason. I recommend checking the Front / ALS / Proximity circuit.
