Common faults in notebooks: How to solve white screen when booting

1. Sometimes when we use the computer, we will encounter the situation of booting white screen. In fact, this does not need to worry too much. The white screen of the laptop is a common fault of the notebook. The problem is that there is a solution, the next time you encounter the need to worry, then how to deal with the white screen of the notebook. Xiaobian introduces you to the reason why the laptop turns on the white screen? Steps/solutions.

With these questions, we will give a detailed answer to the meaning of the white screen of the notebook and the murderer who produces the white screen on the laptop. First of all, the white screen is our terminology in the computer repair industry. The notebook boot light can be lit. The screen is blank and there is no boot screen display, but you can hear the sound of entering the windows. Everyone should know what to do when using the laptop. Whether the white screen and the white screen are related to the graphics card, just connect the laptop and the pc monitor to the boot to see if the display is normal (usually there is an external PC monitor port behind the laptop). If the pc display and the notebook screen display are both white, the possibility of damage to the graphics card is higher. The graphics card of the notebook computer is divided into two sets of synchronous signal output, one set is supplied to the LCD screen and the other set is supplied to the display port, so whether it is connected with the graphics card is the best test method is to connect the pc display.

2, now we take the customer to repair the Lenovo Zhaoyang (legend) s300 laptop as an example, the fault is the boot white screen. According to the customer, the occasional screen will flash, and when the flashing is severe, the computer will be flashed and eliminated. I feel that it does not affect the operation, so I have been ignoring it. But one day, once again, the screen will be blank and I will only hear the sound of entering the windows. I suspect that there is a problem with the contact. There are four rubber particles covering the four corners of the laptop screen, so we must be careful when disassembling. Whether there are screws around to avoid damage to the outer casing, but also pay attention to the uniform force when removing the outer casing, do not press the hand on the screen, so as to avoid excessive force and break the screen, the consequences are more serious, the right side of the screen is placed on the right side. The high-pressure strip lamp tube interface is connected with the high-pressure strip. If the lamp tube connection port is to be disassembled, it can be started only when the sub-shut is turned off. Because the high-voltage strip is powered by the main board 15-19 volts, the high-voltage strip is passed through the high-voltage coil. The 10 volts are converted to kilovolts to illuminate the lamp, so the high voltage coil also has a label indicating: high voltage (caution: high voltage).

3, the high voltage bar is powered by the main board 15-19 volts on the high voltage bar, after the high voltage coil, the 10 volt voltage is converted into a kilovolt voltage to illuminate the lamp

Remove it from the high pressure strip and gently put the screen down and we can see the connection between the screen and the motherboard. In the lower left corner, the screen line is obviously fixed firmly. To rest assured, we still reconnect the interface once. We look at the model of the screen (torisan-tm121su-02l07) 800*600 resolution. The low-divided screen of this interface is rarely seen on the market. In 2000, most of the screens of this model were used in acer and legend. Inch tft thin and light notebook, now most of the laptop LCD screen mainstream is based on 1024 * 768 or 1400 * 1024 high score screen. There is also a connection line above the interface. This connection line is supplied from the output voltage of the screen circuit board to the resolution module of the screen. For the lack of color of the screen, it may be caused by the resolution of the output voltage of the module. The screen motherboard chip sets multiple voltages to the module through the connection line, and the module outputs a steady current voltage to the display transistor to illuminate, but for the white screen case, the resolution module current voltage is not input, so we can eliminate the connection line because the looseness produces the boot white Screen, the resolution module's role: to distinguish the steady current voltage to the transistor for the normal display color of the display. It should be mentioned that in daily life, we can often see that there are one or more bright lines in the LCD screen, and it is suspected that the screen is caused by contact problems. The cause of the bright line is caused by the breakage of the transistor, and the violent impact makes the voltage unstable and the transistor is broken. So the laptop has to go through several violent impact tests when it leaves the factory. This is also one of the tests on the LCD screen.

4, the screen cable contact us basically check and deal with, then we look at the motherboard connection position is loose, after the keyboard cover is opened, we found the connection between the LCD screen and the motherboard A chip (ds90c313mid) is used to control the voltage regulation of the screen. When the screen is protected or hibernated, the chip will control the voltage input and output to reduce the screen power consumption. (We should find that in the use of the computer, we just put the screen and the host on the screen will automatically go to sleep and when you open again After the screen will automatically light up) After all the interfaces are reconnected, we try to boot again ------- This laptop still appears to be booting white screen, the fault is still not eliminated, and finally we take a deep step Check whether the voltage input and output are normal. After opening the adhesive tape on the cover screen board, we can see that the main chip of the control screen (torisan-sla402f4d) has 168 feet on all four sides, causing the white screen murderer to be the chip. We can't pack the ticket after the test, then we use the instrument to measure it. First, we use a multimeter to measure whether there are 4 sets of 3v voltage input at the interface for the chip output, input, and then measure the small capacitance around the chip. Whether the diode has a power input, as the author expects that the input voltage at the screen interface is normal and the output of the chip is abnormal. Stream output, first encountered such a situation we have to determine the chip is damaged, so we have to get back the same types of chips in a bad LCD screen of the same model it replaced. (It should be noted here: when using a hair dryer to heat the chip, pay special attention to temperature control, because the bottom of the chip is a thin layer of liquid crystal film, so the heating process should pay attention to temperature regulation, high may be Backlighting paper causes white spots, and the chip pins are broken when the chip is not blown.

Precautions

After replacing the LCD screen, the LCD screen is loaded back into the test machine. Hearted " core & rdquo; people! The real white screen of the murderer is (torisan-sla402f4d) caused by this chip, troubleshooting.

As a common fault in laptops, I hope you can take a good look at the above reasons and solutions, because this problem is more likely to occur. It is best to leave a mind when you encounter similar problems in the future. I can solve it myself.