Real solution for iPhone 6 Plus LCD screen no display after boot
The iPhone 6 plus LCD screen no display when booting, and is shows short circuit connection. The device was dropped as the screen is broken.
Disassemble the device and the power short-circuit current is more than 700 mA, observe the motherboard under the microscope. As shown in picture 7–6–1 and 7–6–2.
Backlight IC is placed directly on the top, we also find that the screw column is broken, there must be a broken line. After the measurement of power supply, it shows PP1.8V, PP1.8_SDRAM are short circuit. 1.8V power supply connected to the original components as shown in picture 7–6–3.
Decisively take off the black touch welding on the 5 large chips and some capacitors, 1.8V short-circuit is excluded. Check the PP1.8_SDRAM power supply, and the original components are shown in picture 7–6–4 and 7–6–5.
There are 6 chips in this power supply, a little bit of trouble to take them off, so direct burning the device. When the current is adjusted higer slowly, it is found that the power IC is heated and the short circuit fault is removed after taking off. Switch on the power IC and boot, the current 0mA — 60mA jump back and forth, this situation is mostly CPU did not identify the upper layer caused by, is the upper blowing empty?
The screws column is damaged, blow the screws, the 6P right screw has a 12C bus wires, and if the 12C is short-circuit, it will cause the upper layer cannot be identified. Scraping the screw column and finding a broken one, so we solder with jumper wire. As shown in picture 7–6–6.
After the wire is repaired, the current jumps normally. Replace the chip directly, soldering jumper on black touch M1 pin. As shown in picture 7–6–7.
Handle them all, the iPhone 6 plus can be turned on normally. As shown in picture 7–6–8.