- Check the various cable connections first.
- Check to see if there is a burnt or damaged cable.
- Check to see if there is a disconnected or loose cable connection.
- Check to see if the cables are connected according to the connection diagram.
- Check the power input to the Main Board.
- Check the voltage in and out between the SMPS ↔Main Board, between the SMPS ↔X, Y Main Board, and between the Logic Boards.
CHECK POINTS BY ERROR MODE
SYMPTOM
- The LEDs on the front panel do not work when connecting the power cord.
- The SMPS relay does not work when connecting the power cord.
- The unit appears to be dead.
The SMPS relay or the LEDs on the front panel does not work
when connecting the power cord if the cables are improperly connected or the
Main Board or SMPS is not functioning. In this case, check the following:
- Check the internal cable connection.
- Check the fuses.
- Check the output voltages of the SMPS.
- Replace the Main Board.
TROUBLESHOOTING PROCEDURES {Click on pictures to Enlarge}
THE UNIT IS REPEATEDLY TURNING ON AND OFF
SYMPTOM
The SMPS relay is repeatedly turning on and off.
MAJOR CHECK LIST
- In general, the SMPS relay repeatedly turns on and off by the protection function due to a defect on a board connected to the SMPS.
- Disconnect all cables from the SMPS, operate the SMPS alone and check if the SMPS works properly and if each voltage output is correct.
- If the symptom continues even when SMPS is operated alone, replace the SMPS.
- If the symptom is not observed when operating the SMPS alone, find any defective assemblies by connecting the cables one by one.
Caution
WHEN SEPARATING AND CONNECTING THE CABLES SUCH AS CN810,
CN809, CN808, CN807 OF THE MAIN SMPS, CN4701 OF THE X MAIN BOARD, AND CN5707 OF
THE Y MAIN BOARD, A SPARK MAY BE GENERATED BY THE ELECTRIC CHARGE OF THE HIGH
CAPACITY CAPACITOR. THEREFORE, WAIT SOME TIME AFTER DISCONNECTING THE POWER
CORD FROM THE UNIT.
AUDIO OK, BUT NO PICTURE
SYMPTOM
- Audio is normal but no picture is displayed on the screen.
- This may happen when the Main Board is functioning but the X, Y Main Board, Logic Board, or Y Buffer Boards are not.
- The output voltage of the Main SMPS.
- This may happen when the LVDS cable connecting the Main Board and the Logic Board is disconnected.
TROUBLESHOOTING PROCEDURE
Caution
WHEN SEPARATING AND CONNECTING THE CABLES SUCH AS
CN810, CN809, CN808, CN807 OF THE MAIN SMPS, CN4701 OF THE X MAIN BOARD, AND
CN5707 OF THE Y MAIN BOARD, A SPARK MAY BE GENERATED BY THE ELECTRIC CHARGE OF
THE HIGH CAPACITY CAPACITOR. THEREFORE, WAIT SOME TIME AFTER DISCONNECTING THE
POWER CORD FROM THE UNIT
SYMPTOM
- Video is normal but there is no sound.
- When the speaker connectors are disconnected or damaged.
- When the sound processing part of the Main Board is not functioning.
- Speaker defect.
TROUBLESHOOTING PROCEDURE
NO VIDEO
SYMPTOM
- A normal/cable network analog broadcast screen is blank or abnormal but OSD is OK.
- Check the antenna connection settings (Air: NTSC / ATSC, Cable: NTSC)
- Check the CVBS cable connection.
- Check the power input of the Main board.
TROUBLESHOOTING
DRIVE BOARD TROUBLESHOOTING TABLE
SMPS TROUBLESHOOTING TREE
CLICK ON THE PICTURES TO ZOOM IN
