Troubleshoot: there is no service on iPhone 6

Customers sent us an iPhone 6 to repair; the faulty is that there is no service on iPhone 6. It's been repaired, but it's not fixed.
After we received the iPhone 6, we started checking the iPhone. We can't find the operator in manual condition. As shown in picture 8-3-1.

 Disassemble the iPhone 6 by phone opening tool, take out the motherboard, we can found that the colleague has been repaired RF parts, now we need to fix it step by step.

Let's start with the easiest. Soldering jump wire on U1、V1 pin, still no service. Because the colleague repaired too many chips, as long as the chip on the RFFE bus has problems, it will affect this. Remove all chips except 2G power amplifier on RFFE bus, the iPhone still no service. Then we replace the antenna switch and RF IC, the problem still the same. It seems that colleagues have amplified the problem.

Now we use multimeter to measure the power supply on RF IC U_WTR_RF, we found that the resistance at both ends of the R38808_RF resistor on VDD_XO_2V power supply is incorrect, one side it 438, the other side is 564. U_WTR_RF and R38808_RF in the circuit diagram position as shown in 8-3-2 and 8-3-3.

When we use multimeter Lead Probe to press it, it's back to normal, so we can judge that the resistance is virtual welding. Now we find the problem, so we solder it with soldering station. After finish it, we assemble the iPhone and test it, the signal was back.
Finally, we put the removed RF IC back in iPhone motherboard. The repairs end here!

 

iPhone screen is unfortunately broken, what can we do?

The iPhone display screen problem is a common problem for iPhone, and there are many peoples have this trouble. However, as the saying goes, danger is next neighour to security. If you are facing this problem, then congratulation, you are in the right place, this article will provide some suggestions to your to fix it, and you will learn more things about iPhone repair from Vip Pro Shop Team.

1. Check your iPhone warranty period. If it's still under warranty, the APPLE repair center is the best choice. You can send it to the local APPLE repair store, and tell them what the problem is, they will help you to fix it. Because it's still under warranty, it won't cost much.

2. Professional repair Shop. If your iPhone is not under warranty, you will cost much when you want send it to APPLE repair store. In this case, you can choose the professional repair shop, which with the good credit. It also can fix your iPhone screen, and it's price will be cheaper than that of Apple. But, you need to choose the phone repair shop carefully; otherwise, they might damage your phone.


3. DIY fix it by yourself. If you have some knowledge of phone repair, it's easy to replace the display screen of the iPhone. This is also an option worth considering; Its cost is very low. In this case, you need to prepare all the repair tools you needed, the LCD display screen, phone screwdrivers, tweezers, sucker and so on. All of this phone repair tools you can find it in Vipprogrammer, which is the high-quality phone repair tool shop. Otherwise, you can find many video of replace screen on YouTube. Just remember this, when you are in operation, you must be more careful.

Whichever you choose, it's all about fixing your phone screen. When you fix it, please remember to use it carefully. And i hope this article will help you to solve this problem.

You can consider the above suggestions, and if you have better advice, please share with us.

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!

Real solution for iPhone 6 reports iTunes error 9 56

 According our experience, after the iPhone drop into ground, and then it reports iTunes error 9 and 56 when we root it.  Most of this case is caused by disconnection from CPU to logic IC and NFC IC.  The main CPU chip and PCB board  has the bad connect after iPhone dropped, so the iPhone will shows situation of not boot or iTunes error code .

The iPhone 6 reports iTunes error 9,  disassemble the iPhone by repair toolkit, and check the line from logic epprom IC to CPU, there is a test point with false soldering.  Soldering jump wire directly from CPU to logic epprom IC. As shown in picture 1.

 

Scraping the CPU off slowly and find the signal point to solder jump wire. As shown in picture 2.

Soldering jumper on the position where the chip are connected, and the iPhone can be directly switched into the system after the connection is made up. After the customer go back for a few days, the device reported error 56 again, error 56 is caused by the broken wire from NFC to CPU or damaged NFC chip, firstly we remove the NFC chip. As shown in picture 3.

NFC chip is diconnected and most of solder points are dropped, it's all blank for the places without wire end, so soldering the useful two points with solder iron. As shown in picture 4.

Reload the chip, and then root it again, the iPhone 6 can work normally.

iPhone 5S can’t receive calls, the real solution is here!

No matter what electronic products are repaired, the first step is to understand the structure of the machine, and then differentiate the faults. For example, Apple iPhone is divided into two main parts:

1. AR part is the boot part.

2. BB part is baseband part, which belongs to the phone call part.

Now the fault of this iPhone 5s is it can boot, just sometimes it can call out, but can't receive calls. We can determine the fault is in the baseband section and then start measuring.

1. Enter *#06#, we can see IMEI number, which means the baseband has no problems.

2. The problem of reception and launch is generally RF power supply.

3. We can detect the SIM card, which means receive part is normal, now we need to test the launch part.

4. Open the schematic diagram, and then find the RF power supply IC U11_RF. As shown in

picture 7-7-1 and 7-7-2.

Find this chip on iPhone 5s motherboard, as shown in picture 7-7-3.

Measure the power supply and output of the chip with multimeter. Fist we measure the PP_BATT_VCC_CONN on C1215 capacitance, it has a voltage. But PP_PA has no output voltage, so we suspect the RF chip is damaged.

This chip can be replaced or directly connected (solder the jump wire between two pins under the stereo microscope). As shown in picture 7-7-5 and 7-7-6.

After soldering jumpwire, assemble the iPhone 5s and test it, everything is normal.