Cleaning method is generally used to solve the problem that the motherboard cannot work normally because there is too much dust on the motherboard and the dust has static electricity. You can use a brush to clean the dust on the motherboard.
In addition, there are many external boards connected to the motherboard, and the gold fingers of these boards may be oxidized, resulting in poor contact with the motherboard. This problem can be erased with an eraser. The observation method mainly uses the skills of "seeing and touching".
After turning off the power supply, check whether the components are connected correctly, whether the capacitor and resistor pins are in good contact, whether there are burns or cracks on the surface of the components, and whether the copper foil on each circuit board is burnt out. At the same time, you can touch the surface of some chips by hand to see if there is any very hot phenomenon.
2. There are several ways to repair the mobile phone motherboard.
Maintenance methods Motherboard failures are often manifested as system startup failure, no display on the screen, sometimes it can be started and sometimes it can't be started, so it is difficult to judge intuitively.
The maintenance principle of "seeing, listening, smelling and touching" is generally adopted when checking and repairing mainboard faults. Is to observe the fault phenomenon, listen to the alarm, smell the smell, and touch some parts with your hands to see if they are hot.
The following lists several common mainboard maintenance methods, each of which has its own advantages and limitations, and generally requires a combination of several methods. Cleaning method is generally used to solve the problem that the motherboard cannot work normally because there is too much dust on the motherboard and the dust has static electricity. You can use a brush to clean the dust on the motherboard.
In addition, there are many external boards connected to the motherboard, and the gold fingers of these boards may be oxidized, resulting in poor contact with the motherboard. This problem can be erased with an eraser. The observation method mainly uses the skills of "seeing and touching".
After turning off the power supply, check whether the components are connected correctly, whether the capacitor and resistor pins are in good contact, whether there are burns or cracks on the surface of the components, and whether the copper foil on each circuit board is burnt out. At the same time, you can touch the surface of some chips by hand to see if there is any very hot phenomenon.
I want to repair my mobile phone. What should I know?
In fact, all mobile phone interfaces have foolproof design, that is, if the interfaces don't correspond, they can't be plugged in, so the most basic thing is not to disassemble or lose parts. Those so-called professional maintenance are actually just taking out the parts and changing them. The most common thing is to change the motherboard whenever there is a problem, and then take it to the manufacturer who really understands the electronic system for repair. The difference between the two is profit, because the motherboard given to you is often the worst compatible motherboard.
Common faults are mainly judgment ability, but most of them are chip problems, which cannot be repaired and can only be replaced. The so-called system is just a lie. LZ found an unwanted mobile phone and took it apart to see the layout. It will reach the level of those so-called professional maintenance personnel in an afternoon, but it is not as fast as others.
4. Tell you some common sense of mobile phone maintenance.
Learn the basic structure, basic working principle and basic welding practice of mobile phones, systematically learn the working principle of various brands of mobile phones and the maintenance methods of common faults, and learn the operation methods of software such as upgrading, downloading and disassembling programming.
First, the basic knowledge
1. Understand the performance and function of basic components such as capacitors, resistors, inductors, diodes and triodes.
2. Be familiar with the principle and function of oscillation signal.
3. Master the principle and practical application of various amplification circuit diagrams.
4. Master the working principle of single chip microcomputer and its application in mobile phone.
5. Master the principle and application of integrated circuits in mobile phones.
6. Master the scientific use of various maintenance tools and instruments.
Second, mobile network knowledge
1. Understand all kinds of knowledge of mobile networks and the development of various networks.
2. Understand the relationship between network and mobile terminal.
3. Understand the use and function of various functions of mobile phones.
5. What professional knowledge do you need for mobile phone maintenance?
After determining that the mobile phone hardware is damaged, it will enter the stage of mobile phone fault finding and maintenance. General mobile phone maintenance is divided into four steps.
1, looking for fault clues
This step includes asking users about their usage, such as whether they have fallen, whether they have been flooded or not, and whether they have been repaired. Although this step seems simple, it plays a vital role in judging the cause of the fault, narrowing the scope of the fault and improving the maintenance efficiency. Some obvious injuries are invisible to novices, but experienced maintenance personnel may be able to see them at a glance, which fully demonstrates the importance of this step. When looking for fault clues, the following methods can be used.
2. Narrow the fault range
After finding the fault clue and replacing the faulty components, if the mobile phone still can't work normally and the fault appears repeatedly, we can further judge the faulty module by replacing it.
3. Maintenance of component electrodes
This step is to find and replace the faulty component, which is based on the accurate judgment of the faulty module, otherwise it is likely to cause a "headache".
4. Test the whole machine and record the maintenance log.
After troubleshooting, the function of the machine should also be tested to make it fully meet the requirements. For some software faults, it is necessary to conduct power-on debugging for a long time to see if the faults will reappear, and then hand them over to users after the faults are completely eliminated.
Keeping a maintenance log is like a doctor recording a medical record. Every time the machine is repaired, the following records should be made: what machine it is, what faults it has, and how long it has been used; How to repair it, what detours have been taken, and so on. These maintenance logs, which seem to increase the workload, are actually a good way of self-learning and upgrading, and also provide a reliable basis for repairing similar mobile phones or similar faults in the future.
6. What is the common sense of mobile phone maintenance?
If you can't install the system with software, you can do so. If you have a hardware fault, you can judge the hardware fault by listening to the computer alarm.
BIOS settings only learn how to start the computer with CD-ROM drive, USB flash drive and hard disk, save the settings and restore the default settings of the motherboard, and the rest need not be learned, which is generally of little use to amateur computer enthusiasts.
Learning computer only needs to learn a few common English. You don't need more.
Computer software failures are more than hardware failures. Hardware failures are nothing more than the memory and graphics card being used for a long time and the slots being oxidized. At this time, the problem can be solved by removing the golden finger from the eraser of the graphics card and memory.
The computer automatically shuts down and restarts, mainly because there is too much dust on the CPU fan. If it is not cleaned, it is necessary to change the big fan.
Computer card, the crash is due to a lot of computer debris, use your own system tools to clean up the debris, it is best to thoroughly disinfect, and then use security guards to optimize the system.
The computer is broken. Install the system first. If it can't be installed, it is considered that there is something wrong with the hardware.
When the computer starts with a blue screen or fails to start, it will automatically restart when it starts, and the same is true when reinstalling the system. At this time, in addition to checking whether the internal thickness is inserted tightly, clean the fan and look directly at the motherboard. Perhaps the motherboard capacitor is damaged/
The computer has been used for a long time, and the wiring of each hardware is easy to loosen. Take it off and plug it with your hands.