Skip to main content

iPhone 6S doesn’t respond to boot—How to fix?


After pressing the iPhone power button, the iPhone 6S doesn't respond to boot, the iPhone screen keeps black.  Before the iPhone 6S got this problem, it works fine, after we charge it, the problem arises.  After plugging the iPhone lightning cable to charge it, the iPhone charging icon appears abnormally, after few seconds, the iPhone turns black.  How to fix this problem? 


Based on our repair experience, we suspected that it's the problem of the iPhone charge part. Open the WUXINJI Dongle to check iPhone 6S schematic diagram, we know that there are  three components are directly related to the charge part, they were Q2300, U2300 and U4500. Now we start to repair.

Disassemble the iPhone 6S, take out the iPhone motherboard. Measure the iPhone motherboard with DPS DC power supply, the boot current jumps from 200mA, it's abnormal, because the normal current should be around 40mA, it's short-circuited.

This phenomenon is mostly caused by the short circuit of the iPhone main power LDO power supply. 

After checking iPhone schematic diagram, we know that the PP3V0_TRISTAR and PP3V3_ACC this two are supplied by all LDO power supply, so the most likely damage is the USB U4500 IC. 

Use QUICK 861DW hot air rework station and tweezers to remove the USB IC, and then measure it again with DC power supply, the  boot current is about 40mA, then replace the iPhone USB charge IC. After replacement, measure the iPhone again, the current is normal. 


Install the iPhone 6S, now the iPhone has response when press the power button, and it entered the IOS successfully.  Charge the iPhone with iPhone lightning cable, it works properly. 



Comments

Post a Comment

Popular posts from this blog

Complete Guide to Replacing Your iPhone Battery at Home

  Has your iPhone battery started showing the dreaded signs of age, like frequent charging, rapid draining, or even an untimely shutdown? Are you considering a battery replacement but feeling deterred by the potential cost or hassle of a trip to the Apple Store? Don't worry; with the right guidance, you can replace your iPhone battery at home quickly and safely, sparing your wallet and ensuring a future of longer charge cycles for your beloved device. Whether you have the latest model or an older version, we'll walk you through the process step by step. But before we get into the nitty-gritty, here's why a battery replacement might be in your best interest. Why You Should Replace Your iPhone Battery The lithium-ion batteries in our smartphones are not immortal. They degrade over time due to a variety of factors, such as age, temperature, and the number of charge cycles. Replacing an old battery can provide several benefits: Improved Performance: A new battery can result ...
Post a Comment
Read more

User Manual: JC V1 Programmer to fix iPhone light sensor/vibrator

As we know, the light sensor and vibrator is very important for iPhone screen. If you want to replace the iPhone screen, you also need to transfer the original screen data to the new iPhone screen(iPhone 8 to iPhone Xs Max),so you can make sure the new iPhone screen will work fine. Here is a  JC V1 programmer  to fix iPhone light sensor and vibrator problem (for iPhone 7- iPhone Xs Max), it also can repair iPhone baseband eeprom IC or iPhone logic eeprom IC problem. The JC V1 Programmer comes with 24-inch HD display screen, three-color LED indicator light, two small connecting seats (for connecting function panel) , two buttons and one function panel (including light sensor/touch connector, baseband function connector, vibration connector) It support 2 languages (Chinese/English) and three lines of code (read/write/burn/save), the function panel can be changed, the software can automatically update What’s the functions? - Repair iPhone Light sensor/ true ...
1 comment
Read more

Here: JC P11 iPhone Nand Test Fixture Specification Details

JC P11 iPhone Nand test fixture is on sale now, some users still confused for it, what's credit points for JC P11? Why it's cheap? As we know, JC P11 BGA110 programmer is the latest programmer for iPhone   iPhone XS Max,XS, X, 8P, 8  and iPhone 11 Pro max/pro/11, which is made by JCID factory.  Here are some  specification details for JC P11 programmer . 1. Main Functions. - Support to modify and write BGA110 NAND SYSCFG data (NAND Flash underlying data, such as SN/BT/WIFI and others); Unbind WIFI. - It doesn't require restoring the firmware for brand-new Nand flash, the SYSCFG data can be written directly. - Repair the Error 35 during firmware restoring for BGA110 NAND - Repair the DATA Error for BGA110 NAND - Support iPhone 8/8P/X/XS/XS Max currently, free software upgrade to support 11-11Pro Max in the future - Initiate the network charging mode, can purchase the points according to the demand, which greatly saves the equipmen...
Post a Comment
Read more