Why the TV does not turn on, but the indicator is on or flashing


Breakdowns of television receivers, like any electronics, can be caused by various reasons, which are sometimes difficult to get to the bottom of. Devices both new and used for a long time are prone to failures. For example, when you try to turn on the TV receiver, you see the indicators flashing, you hear a clicking sound, but the TV still does not turn on and does not work. Different models of devices may have their own “symptoms”. There can actually be many reasons why the TV does not work.

Turning on the TV

Continuous indication

If the indicator is constantly on, it means that power is being supplied to the equipment. When the TV cannot be turned on with the remote control, it is worth trying to do this from the main panel on the TV. It is quite possible that The problem is in the DPU.. If the equipment is turned on, then you need to check the remote control.

Diagnosis of DPU:

  • open the compartment with batteries and check if the contacts are oxidized;
  • inspect all buttons for sticking;
  • check the integrity of the emitter;
  • clean the remote from dust and other dirt.

replacing batteries in the remote controlBatteries in DPU could be exhausted. When the LED on the emitter glows brightly enough and looks intact, it is worth bringing the remote close to the main panel and trying to turn on the TV. If this succeeds, then the batteries must be replaced with new ones.

Red indicator light

When the indicator glows red, then, most likely, the equipment is in standby mode. If the TV cannot be turned on at the same time, it is worth checking the operation of the main board. It is necessary to inspect all capacitors for swelling and, if necessary, replace them, and then make a control call of all elements with a tester. It would also be useful to check the power supply with the same multimeter.

swollen capacitors

If a short circuit occurs, or one of the burnt elements led the AT24 memory chips (Eeprom, SpiFlash), then you will need software update. When installing the software using the local interface is not possible, you will have to flash it using the programmer.

If everything is OK with the main board, but the TV cannot be turned on, you should check the power circuits on the system board. It houses voltage converters, DC-DC modules and other secondary sources. The first thing to find out is the stability of the power supply in a given voltage range. Board diagnostics is carried out using a multimeter.

board diagnostics with a multimeter

Advice! It is better to entrust such work to the specialists of the service center.

The indication changes from green to red

Having received a signal from the control panel, the processor instructs the executing elements to exit sleep mode and turn on the equipment, displaying a corresponding notification on the main panel. That is, the indicator changes color to green from red.

If the alarm LED on the control panel switches back to red, then one of the circuits is not following the command given. Here the problem may be in the inverter, which is not able to turn on the backlight, or in faulty power supply, blocking the start of the equipment.

In such cases, the processor switches to standby mode: the indicator lights up red without blinking. For example, the processors of some Sharp brand TVs, after five attempts, put the system into a complete lock. That is, the TV cannot be turned on without resetting all parameters through the service menu or completely flashing the AT24 memory. Other models perform self-diagnostics when attempting to start until the cause of the problem has been corrected.

The indicator is green, but the TV does not turn on

There could be many reasons for this. Perhaps the logical processes were broken as a result of an accidental power outage at the time of their execution. First of all, you should try to force update the software with the programmer. After flashing, the logical processes should return to normal sequence.

Next, it is necessary tocheck the functionality of the main board: ring the main elements, make sure that the voltage is sufficient and stable, and also examine the details of the backlight. If there is no image on the screen, but there is sound, then most likely the cause of the malfunction is the inverter or the LED unit responsible for supplying power.

Disassembled LCD TV

Sometimes the motherboard blocks the reception and transmission of all signals to the controllers, or sends incorrect commands, in which the matrix remains inactive. The latter may also be faulty.

Ultra-budget models are equipped with far from the most adequate TCON chips. They receive commands from the video controller and are responsible for converting signals for the LCD matrix. In some cases, a complete flashing of the chips helps, with an eye to the specifics of the main board of the TV.

Chaotically flickering indication

When the LED lights up in a chaotic manner: it blinks at different frequencies or goes out for a few seconds, and then turns on again, but in a different color, it is quite difficult to identify the cause of the malfunction. Needed here complete equipment diagnostics.

It is better to start with the power supply, and then go to the main board, checking all the elements of the circuit one by one.

You should also examine the interfaces for connecting third-party peripherals. It happens that closed contacts on one of the ports block the operation of the entire system.

TV connection interface

Indication inactive

If the indicator does not light up at all, then the problem is most likely in the power supply. It would be useful to check the performance of the TV without looking at the LEDs. It is possible that the latter simply burned out. In other cases, consider the following reasons.

  1. Faulty outlet. You can check it by calling, or by connecting any household appliance, for example, a hairdryer or a table lamp.
  2. Burnt Wiring/Extension. If the smell of burnt wires is not felt, then we check the cord for physical damage — breaks and breaks. It is worth trying to replace the carrier / extension cord.
  3. The «Network» button on the TV is inactive. The key is used to switch the TV to standby mode: the indicator lights up in red. It may have been accidentally pressed to the off position.
  4. Wrong mode. The TV can operate in several modes. If the broadcast takes place, for example, via AV, and the PC is on, then the TV may turn off due to the lack of a signal.
  5. Blown fuse. For older TVs, the problem is especially relevant. Fuses are usually located on the rear of the equipment. The burnt part gives itself out as a broken wire inside a glass bulb. We replace it with a similar one and try to turn on the TV.
fuses on tv

Fuses in the TV

TV beeps

There are times when the TV beeps when turned on. When the whistle appears for a short time after turning on, this indicates a faulty PSU (power supply). Capacitors that have lost their capacitance can cause such a sound. After some time of operation, the sound may become constant, which is a sign of an imminent PSU failure.

If the LG TV does not turn on and at the same time starts to squeak, then a more serious repair of the unit will be required. Such a nuisance can also be visited by BBK, Sharp, Bravia, and Toshiba TVs. Whistling can then be caused by a load in the secondary circuits due to:

  • burnt line transistor;
  • closed capacitors;
  • a failed line chip.

When kinescope apparatus, for example, TV Vityaz or Rubin, often squeaks TDKS due to a cracked case. This can happen during long-term operation of the unit. The sound is caused by the flow of a high-voltage discharge onto neighboring elements. If it is problematic to replace TDKS, then you can try to fill the problem area with epoxy-based glue.

On a TV, the Horizont can make a kinescope whistle with a poorly fitting suction cup, due to dust accumulated under it.


Transistor Sharp 54CS-03S

TV does not turn on for a long time

Your Philips TV may not turn on the first time after some time of use. It takes 3-4 minutes to turn on the TV, and attempts can be from 10 or more. At the same time, as soon as the image begins to appear on the screen, it makes a click and turns off. Such symptoms are also inherent in Sharp, Thomson, Rubin and Daewoo devices. When the TV clicks and does not turn on, this indicates faulty power supply capacitors. After turning on the power, due to insufficient electrolyte capacity, the Philips PSU goes into protection.

The device is blocked after switching on

The blocking pattern can often be observed on a Toshiba TV, and it does not matter if it is an LCD TV or a plasma TV. This happens as follows: after 3-4 seconds, the switched on unit goes into shutdown and is blocked, and a circle starts to burn in the upper left corner, and the TV does not show. To solve the problem of why the TV does not turn on, you must first measure the voltage on the system board. If the indicators are normal, it remains only to do software flashing.

TV receiver freezes

Turning on the TV receiver, you see the display of the SmartTV splash screen on the screen, while the indicator blinks 5-6 times and the device “freezes”. After that, the Samsung TV does not turn on either from the remote or from the panel. There is a response only when you press the shutdown button on the remote control (the red indicator flashes), but the telly does not think to turn off at the same time. What to do? Then the only thing that can be done is de-energize the unit.

Sometimes it does not show the TV due to a failure in the software shell — it will need to be flashed in a service center. In rare cases, such symptoms can be observed when the CPU, or rather its memory module, malfunctions.

The unit randomly turns off or on

Such strange behavior has been seen with Rubin TVs. The device may spontaneously stop working after a certain period of time. Or vice versa, the TV turns on without anyone’s participation. The reason for the shutdown of the device may be faulty power board. Also, failure of the control board cannot be ruled out. Spontaneous inclusion of the Rubin television receiver can be:

  • with a faulty power board;
  • when closing the contacts under the keys on the remote control;
  • closing the buttons on the TV panel.

Sharp televisions also notice spontaneous switching on, after which it turns off, and the indicator starts flashing red. The failure is the same — the power supply or the power board.

Most of these problems, other than repairing or replacing the remote control, and checking the power cord, should be repaired by qualified personnel. To do this, they have the necessary knowledge, tools and diagnostic equipment. You can learn more about other TV problems that can be repaired by yourself in our TV repair article.


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