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How to Find and Repair Cell Phone Faults?

Cellphones are essential around us now, so the possibility of faults causing are also increasing. There are plenty of factors for cell phone faults. Do you feel frustrating and have no idea how to solve it?  I  will share 6 method to help you find cell phone faults, and the ways for how to solve these problems.



• Multimeter Measuring

Multimeter measuring is an universal method, it mainly measure the current, voltage, resistance or capacitance of smartphone parts, then compare the actual values with standard values. Thus you can locate the possible scale for faulty components. of course you need to measure the specific components by multimeter again to ensure the final fault point.



• Oscilloscope Measuring

It is one of the most important method, technician mainly observe the signal wareform for circuit board, which will be compared with standard wareform by oscilloscope to analyse and judge the faulty parts. 



• Spectrum Measuring

Spectrum analyzer is the most scientific and accurate method for smartphone RF circuit parts, it mainly observe relative signal spectrum by the analyzer and then compare with standard information.
For instance, if you want to test the RX  signal of RF circuit parts, it's very convenient to distinguish if it work well by analyzing signal spectrum on display. 


• Software Repair

Software repair is smartphone maintenance method for faulty software, it should work with computer or programmer to restore software data in smartphones.

So far popular software repair method are including phone non-disassembling and disassembling repair.

The first one is connecting smartphone USB port to computer by engineering cable, writing the software data saved in computers into relative modules of smartphone. It is very easy to operate.



The second one is by disassemling faulty module from circuit board while putting it in programmer, then connect computer with programmer, re-write data on computer and put the module back to smartphone. This method is a little bit difficult to operate, technician should be professional for soldering operation.







And there are 2 easiest ways to find out the faults on cell phones.


• Eyes Observing

It is the easiest and fastest way to judge smartphone fault. Repairman can observe directly on housing and circuit board to find some faults. 

First, try to observe on outer smartphone, for instance cracked screen, damaged body, port etc. Mainly check carefully whether the outer construction is good as normal one, whether the front frame matches back frame perfectly, whether it's soiled on touch screen, etc. 

Second, if there are no obvious faults outside, you can move to the next step to observe the inner parts of smartphones. You can start from 3 parts including PCB, connecting lead and electronic components. Judge from some phenomenon such as whether there is a fracture in the screen line, whether there are burning components, false welding on motherboard, etc.



• Nose Smelling


It is another method by distinguish whether there is burning or unpleasant smell, which will help you find fault trace rapidly. If inner components or parts are burned because of a short circuit, a kind of terrible burning smell, repairmen may judge the possible cause by this method.

Many repairmen often ignore the process in actual operation. Anyway, you'b better to have a try, it may help you to find some traces.


Good luck to your cell phone maintenance, hope our information will help you! 


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