iPhone 7 plus no power repair of trinity IC

We received an iphone 7 plus recently for no power. Our customer told us that when they connected a new battery the motherboard would smoke.

When we received the device we plugged it into our power supply and just as the client said we saw smoke coming from M2800 the trinity IC, often called the touch ic but it is actually just a cluster of coils for several different lines built into one IC. we also saw a 5 amp short on the main power line.

 

First off we removed the trinity IC, which is an ic that contains several coils, to find out which line was shorted. We found the short on the speaker amp line, so then we knew where to look! We flipped the board over to look around the speaker amp circuits and found a burnt out capacitor in the C3404 position.

 

We removed this capacitor and the short was resolved. Next we replaced the trinity IC with a new one and plugged the phone into our power supply. The short was gone so we prompted the phone to boot, the phone appeared to turn on and function normally so we unplugged it and fitted a new capacitor. We then cleaned the logic board and reassembled the device and charged it up for full testing. The device seemed to function perfectly so we returned to the customer who was very happy to have their device back fully working.

 

We have seen similar issues with shorts causing the trinity IC to fail but this was a first on this particular line, this is why we love board level repairs, each one is slightly different and you have to think on your toes!

iPhone 6S no power water damage repair

We had an iphone 6s in from a new customer that was reported for not turning on.

We plugged it in to charge through our usb ammeter but had no response at all from our charger.

When we first opened the device we could clearly see that it had had the shields removed and had been cleaned for water damage already. We next checked it plugged into the dc power supply. The phone turned on fine and seemed to have basic functionality.

We removed the board from the phone and found that the device had already been worked on previously, the tigris usb IC and the small audio IC had both been removed, we assume that these were damaged and possibly causing a short originally and that’s why they had been removed. We cleaned the areas and fitted new IC’s to test the phone. We tested for shorts and found none so we plugged a battery and charging port in to see if the phone would now charge. When plugged into the ammeter it appeared to charge up fine so we decided to reassemble the device.

Once reassembled we tested the phone, the battery charged fine, all audio was there, on headphones and both speakers. We where unable to find any further faults so we packaged it up and sent it back to our customer.