The TV won t turn on, and the indicator light won t light up

Start it on with remote control first,Or panel P+,P-,Try to turn it on,If both can't be turned on, then the TV needs to be repaired,If you are doing maintenance, then you should clarify the test voltage,Then it is good to determine the fault range for you,So as to reduce the maintenance time and take fewer detours,First of all, you can't turn it on,Check whether the main voltage is in standby or no output at all,CPU power supply (VCC)、Reset (clear circuit)、Clock line (crystal oscillator)、Whether the data line is normal for power measurement, Small signal power supply and line start circuit, excitation circuit, line output is the focus of inspection, etc.

It is generally caused by the delay in the CPU signal recognition circuit of the TV, and if the delay time is not long, you can leave it alone. If it takes a long time for a signal to appear, it means that the signal identification circuit of the TV is faulty. How is it a bus TV, this fault may also be related to the bus data error or the high frequency head.

The solution is:You can turn off the blue screen function of the TV first,Use the power on to receive the signal for the snowflake state to try。 If there is still a significant signal delay, you can only ask a professional to repair it.

Daily maintenance of TV series

If the TV is not used properly, it will affect the life of the TV.

1. Pay attention to the influence of geomagnetism. The phosphor screen of the large-screen color TV should be placed facing south or north, so that the direction of the earth's magnetic field is consistent with the direction of the electron beam in the picture tube, so as to prevent the geomagnetism from affecting the color purity.

2. Pay attention to ventilation and heat dissipation. When using a large-screen color TV, do not cover it with plastic sheeting, cloth covers, etc., and do not pad foam plastic at the bottom, so as not to affect the ventilation and heat dissipation of the color TV.

3. Pay attention to color and volume. The color, volume, and contrast of large-screen color TVs should be appropriate, so that not only the best effect is good, but also power saving, and it can also extend the life of the TV.

Fault 1: The TV suddenly goes black when it is turned on and the screen goes black after a period of time.

Solution:1、When the TV is turned on,The screen flashes a white light and then the screen goes black,Generally, there is a problem with the high-voltage plate of the TV,At this time, it is best to replace the high-voltage plate,If the high-voltage plate is not replaced,The above situation cannot be fundamentally solved。

2. Secondly, there may be a problem with the power strip of the TV, which will also cause the above situation to occur on the TV. This is because the output voltage of the power strip fluctuates or the power strip works for too long, and the main power supply enters a protective state. At this time, the power board can be replaced with a general high-power 24V8A power board and a 10A power board to make the output voltage of the power board more stable.

Fault 2: The whole machine does not turn on when the TV is turned on and the indicator light does not light up.

Solution: Generally, the circuit of the TV part is abnormal, the internal load is faulty, and the power supply is out of protection, which will lead to the state that the TV does not turn on and the indicator light does not flash.

1. First of all, we use the remote control to turn on the computer, if there is no response, try to press the channel "-" button of the TV, to see if it is a problem with the remote control.

2. The keys of the TV do not respond, the indicator light is on, the circuit output of the power supply board is normal when the multimeter is tested, and the main power supply has no current output, so the button board is faulty.

3. Disconnect the power supply line from the power board to the motherboard, and the power board is forced to start, if the power output of each group of circuits measured by the multimeter is normal, it indicates that the power board is faultless.

4. Select the correct TV screen cable, the blue and white signal line is five teams, and then use a multimeter to measure the screen cable.

5. Check that the screen line is correct, drive the power detection power tool to turn on the power of the TV, observe the TV screen, there is no image display at this time, the TV backlight is lit, and the TV has a gray screen.

6. Use the multimeter again to measure that the power supply of the TV electromechanical screen is normal, there is no voltage after the insurance, and the insurance can be replaced after the power failure.

7. After replacing the insurance, the TV still does not display the image, and there is still no image after upgrading the TV program, use the multimeter to measure the various test points of the logic board, if the abnormality is found, the DC chip should be replaced, the TV voltage is normal, and the screen begins to display the image.

When this machine fails, first check whether the power input circuit components are normal, such as: power supply insurance, varistor, and anti-interference circuit components.

Wait. If the above checks are normal, then measure whether the voltage output of each group of the main switching power supply circuit is positive.

Often. If the above measurement is normal, it means that the switching power supply circuit is working normally, otherwise you still have to check the switching power supply circuit.

Title. At this time, in measuring all DC-DC voltage conversion circuit chips on the motherboard, whether the voltage of each output pin to the ground is normal, if there is any abnormality, check the components around the abnormal feet of the chip.

If the indicator light of the TV does not light up, it means that the power supply circuit of the unit is faulty.

The LCD TV does not turn on, and the indicator light does not light up.

1. Replace the power adapter of the TV. 2. Detect and repair the power circuit part of the TV. 3. Press the "Input Signal" button of the TV remote control and switch to the same source as the set-top box.

4. Open the set-top box. 5. Press the "Standby" button of the remote control once to wake up the TV and return to normal. 6、Need to let a professional master disassemble the machine for inspection and maintenance,If the TV is still in the warranty period,Send it to the TV brand repair shop to warrant。

7. Turn on the remote control first, if it doesn't work, try to press the channel button of the TV again.

There are many reasons, 1. It may be that the power adapter of the TV is broken.

2. The power supply circuit of the TV is abnormal.

4. The set-top box is not turned on, resulting in no image and sound output on the TV.

5. It may be that the TV is in standby, so it can't be turned on, for example, you mistakenly pressed the "standby" button of the TV remote control, so that the TV is in standby.

6. The backlight board of the TV screen is broken or other special circumstances, or it may be that the screen drive circuit inside the TV is faulty due to virtual soldering, or the switch part of the control high-voltage board switch circuit on the AD board in the TV is burned out.

7. It may be that the TV remote control is out of order or the power is insufficient.

The solution to the TV not turning on the power light is as follows:

1. Check the TV power supply if the contact is poor or there is no power.

If the power light of the TV is not lit and the TV cannot be turned on,The first thing to consider at this time is the power supply of the TV,For example, the power supply is not in good contact,Or there is no electricity at all,At this time, the TV cannot be turned on anyway。 We can plug it in again, or we can use the charger to check if the socket has power, and then draw conclusions.

2. The remote control of the TV is out of power or malfunctioning.

The second factor is to look at the problem of the remote control, for example, whether the TV remote control is out of power, if there is no power, the battery must be replaced in time, and the fault needs to be repaired. The detection method is very simple,The remote control can't turn on the TV,There is a button under the TV,You don't need a remote control to turn it on,So you can judge whether it's a problem with the remote control。

3. If the internal parts of the TV are faulty, you need to find after-sales maintenance.

If the above two methods have been tried,Still can't solve the problem,Then even if the internal parts of the TV fail,There are many factors that cause the TV to not turn on,For example, fuse、Rectifier bridge、Filter capacitor、Power switch tube、Power management、Rectifier output diode、Failure of filter capacitors and other components,It will cause abnormal TV startup。 At this time, you can directly find after-sales service.

Fault 1: The TV suddenly goes black when it is turned on.

After a while, the screen goes black.

Workaround:1When you turn on the TV, a white light flashes and the screen goes black. Generally, there is a problem with the high-voltage cable board of the TV. At this time, it is best to replace the high-pressure plate. The above situation cannot be fundamentally solved without replacing the high-pressure plate.

2.Secondly, it may be that there is a problem with the power strip of the TV, which will also cause the TV to appear in the above-mentioned situation. This is because the output voltage of the power strip fluctuates or the power strip works for too long, and the main power supply enters the protection state.

At this time, the power board can be replaced with a general high-power 24V8A power board and a 10A power board to make the output voltage of the power board more stable.

Fault 2: When the TV is turned on, the whole machine does not turn on, and the indicator light does not light up.

Solution: Under normal circumstances, some TV circuits are abnormal, internal load failures, and power supply is out of protection, which will lead to the state that the TV's no-boot indicator does not flash.

2.The TV button is unresponsive, and the indicator light is on. with a multimeter.

When testing the circuit output of the power board, it is normal. If the main power supply does not have a current output, the button panel will be discharged if it fails.

3.Disconnect the power strip from the power strip to the motherboard and force the power strip to start. If the power output of each group of circuits measured with a multimeter is normal, then the power strip is not faulty.

4.Select the correct TV screen cable, five blue and white signal cables, and then measure the screen cable with a multimeter.

5.Check whether the screen cable is correct, drive the power detection tool to turn on the TV, and observe the TV screen keys. At this time, there is no image display, the TV background light is on, and the TV displays a gray screen.

6.Use a multimeter to measure the power supply of the TV electromechanical screen again, and there is no voltage after the insurance. The insurance is open after a power outage, so the insurance can be replaced.

7.After changing the insurance, the TV still has no image, and after upgrading the TV program, measure the logic board with a multimeter.

of the various test points. If there is any abnormality, the DC chip should be replaced, the TV voltage is normal, and the screen starts to display.

It could be the power cord and power strip of the TV.

It's not plugged in, or the remote control doesn't match the model of the TV. Or it is a sign that the motherboard inside the TV is burned out, and there is also a sign that the internal circuit of the TV is not stable. The switch button of the TV and the motherboard inside the TV are not connected stably.

Suggested treatment: 1. The power cord and plug-in board of the TV are not properly connected. In this case,Check whether the plug of the TV is connected to the plug-in board,If not, just connect it,If the remote control and the TV model do not match,This requires you to buy a separate model to match。

2、The motherboard inside the TV is burned out,It may be caused when the TV is used for too long,In this case, it is recommended that the TV is turned off and the TV is disassembled to see if the motherboard inside is burned out。 If it's just because it's too hot, the TV can't be turned on, just let it cool down, if it's a problem with the circuit, it is recommended to consult a professional. 3、There is a problem with the light on the TV that can't be lit,It is recommended to disassemble it to see if there are loose screws inside,If the screws are loose, you can tighten it yourself。

It may be caused by the following orange oak causes:

1.The TV is not plugged into the power cord or the power cord socket is loose.

2.The TV's power switch is not turned on.

3.The TV's power cord or plug is damaged.

4.The TV's power strip is faulty.

5.The TV's motherboard is faulty.

Workaround:1Verify that the TV is plugged in and that the socket is tight.

2.Press the power on the TV.

3.Replace the cord or plug.

4.Contact a professional repairer to inspect the power strip.

5.Contact a professional repairer to inspect the motherboard.