General TV/Monitor Problems and Solutions

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General TV/Monitor Problems and Solutions
Type
Device(s) Television/Monitors
Difficulty
Problem Solution
TV won`t power on. Standby LED blinking.
  • Mostly when the standby LED is flashing, the problem is with the power supply. Check diodes and capacitors, as they are usually the cause of this behavior.
  • Sometimes there can be a problem in the TV firmware; in this situation it is necessary to reinstall the firmware and it is desirable to replace the EEPROM
TV won't power on. Standby LED behaves as expected (on when the TV is off, then off when the TV is turned on) but the TV screen will remain off.
  • This is most likely a power supply failure. It could be a faulty capacitor. This symptom indicates the TV has enough energy for standby, but not for running (especially the display, that is responsible for most electrical consumption). A good troubleshooting step for this is to connect the TV HDMI output to an equipment that can read the EDID information, and see if any information is communicated via HDMI.
TV has sound but no image. Backlight not working.
  • Can be that one or more LEDs in backlight strip is broken, check each LED in strip (start with 2.6 V or 5.7 V PSU, or use the diode check on a multimeter) you can replace the LED that is broken or replace whole strip.
  • Can be that PSU is problem, if LED in strip is good, then is LED driver in PSU unit, depending on the manufacturer, there are kit components for LED driver in PSU unit.
  • Can be the backlight inverter. Beware of the voltage it is meant to output, which is easily above 500 V. Use proper equipment (at least rated 1000 V) when testing it.
  • Check the Y driver board next to the LCD for burnt out Buffer Scan IC chips. These can overheat, particularly on older plasma TV's, and can be replaced.
No sound
  • Check volume, sound settings, and cables.
  • Unplug television, hold down power button on television for 30 seconds, then plug back in.
  • If problem persists, check if the television has an update available or reset television to factory settings.
  • If issue keeps occurring intermittently even after restoring to factory settings, some televisions have a "quick start" mode (standby mode) option where pressing the power button doesn't turn the television off to provide a faster bootup time. Change this setting to full shutdown mode.
TV stuck at Boot Logo or Black Screen
  • Some cheap TVs like Grundig, Telefunken, Dyon, JTC and Kendo (Mainboards made by Vestel) are using a Firmware that tend to self destruction, try to find the correct Firmware for the Mainboard and flash it by using an external Programmer.