There is unknown error (56) on iPhone 6, what can we do?

We can often hear Aplle users say that they will have an error code when they brush their iPhones.  Different unknown error codes are caused by different reasons. Today, Vip Pro Shop Team will tell you what to do when there is unknown error (56) on your iPhone 6.

Unknown Error (56) is the new error code after 6, 6P was released. The two common problems are as follows:

(1) The SIM card should be pulled out before using the telecom number to flash, and then insert the SIM card after the flash is successful.

(2) Camera failure. After iPhone 6, for the mobile phone restore process, when entering into the system firmware, it will be a series of verification, the camera is one of them. In the process, if the camera circuit problems or camera circuit problems there, it will cause error 56.

First pull card slot, no card, eliminate the first kind of fault. Connect special machine to flash iPhone 6, it reports error 56.

Now disassemble the phone and remove the camera to flash, the fault is still existing. (Note: when disassembling and flashing, it's not really necessary to connect  the screen, but the fingerprint(home button) flex cable must be connected up, or it will report error 53 before error 56.) Take off the screen and measure the power supply several times. As shown in picture 7-12-1.

Measuring the 4 voltage below interface, the 1.8V, 1.2V, 1.8V three group shows voltage before camera circuit enter to open camera, 2.85V is only shown when open the camera or flash with camera verification, so long as we measured 1.2V and 1.8V, and the measurement is normal on the iPhone 6.

Next, let's test camera working conditions, in fact,it is to test value. And the measurement needs to directly test the interface, so as to accurately judge. However, besides the pin as shown in the picture 7-12-2, all other pins have resistance: data cable is 400-500, powersupply resistance is 300-400, data cable and power supply cable will never be shown as infinite or short circuit condition.

The fault is found after measuring with power failure,  there is one wire on MIPI bus is tested as infinity, normal resistance and infinite resistance as shown in figure 7-12-3.

MIPI bus (an image transmission bus. Today's smart phone MIPI is the transmission image between CPU and display, or between CPU and camera.  It's very common for 5 differential signal wires 10 wires, 7 groups of differential signal wires and 8 wires, 2 groups of nutrient signal wires 4 wires, while the iPhone 6 camera use 5 groups). 10 wires value should be around 450, the resistance deviation of 10 wires should not exceed 10. And for this phone 90_RCAM_TO_AP_MIPI_DATA1_CONN_P value is infinite, there are only two possibilities: (1) L2338 sense open or false welding so that CPU cannot recognize camera; (2) CPU false weling. This is the MIPI bus in the iPhone 6 camera circuit, which comes from the product J2321 and sends it to the CPU though 5 rows of sense, as shown in picture 7-12-4 and 7-12-5.

Directly measure the sense with multimeter, if it is still infinite words that must be CPU false welding. If the inductance is infinite at both ends, the CPU is open. Take the CPU apart from motherboard first, as shown in figure 7-12-6.

After installation, test the iPhone, all is normal. Then flash it, unknown error code no longer appears!