- Power Supply Board/ M/B Voltage confirmation
- The input and output characteristic test of power
- Intention of test: Check input and output to find if short circuit.
Use Multimeter (VICTOR VC9801) of resistor to check No/Yes short circuit.
Number | Item | Test Point | Standard |
Power Supply | |||
1 | The resistor of AC input | AC Input Connector CON1 | No short circuit |
2 | The resistor of 24Voutput | 24Voutput of connector CON3 | No short circuit |
3 | The resistor of 12Voutput | 24Voutput of connector CON3 | No short circuit |
M/B | |||
1 | The resistor of 24Voutput | 24Voutputof connector XS801 | No short circuit |
2 | The resistor of 12Voutput | 12Voutputof connector F800 | No short circuit |
3 | The resistor of 5Voutput | 5Voutput of connector L804 | No short circuit |
4 | The resistor of 3.3Voutput | 3.3Voutput of connector N803 | No short circuit |
5 | The resistor of 2.5Voutput | 2.5Voutput of connector N808 | No short circuit |
6 | The resistor of 1.8Voutput | 1.8Voutput of connector N804 | No short circuit |
7 | A: The resistor of PANEL5V output B: The resistor of PANEL12Voutput | A: PANEL5Voutput of connector L814 B: PANEL12Voutput of connector L813 | No short circuit |
Verify the state of TV set: switch the TV ON by “Power on/off” switch, Then verify the LED color of touch button. Red is standby state and blue is working state.
Checking Supply Power: If the color of LED is green, the power supply for signal board. F801 supply 5V, N804, N803 supply 3.3V power(Test the PIN 2). N808 supply 2.5V(Test the PIN 2), D806 supply 8V, N804 supply 1.8V. All these are for main IC N001, N401, N504.Digital signal part: Turn on the power => N001 RESET and IO port initialize => N504 electrify, reset, initialize => Turn on back light lamp => Successful start And LOGO display.
- After turning on the power, if blank screen appears (no back light lamp), just press POWER button one times, if blank screen still there.
- Check if the voltage of every power supply is normal.
- Check if the crystal oscillator Z001(22.1184MHz) Z501(14.318MHz) Z400(24.576MHZ) oscillate or not, and oscillate frequency is right or not.
- Back light control signal (BKLON) of XS806 has high level (above 3V) or not, if not, check whether fault soldered or short circuit happened.
- If back light lamp is on while there is no display, check N001 and N504’s reset circuit and the output of the oscillator to confirm the CPU and SCALER are working or not. If RGB is abnormal, check N504;If RGB is working correctly and the other channel is abnormal check N504.
- Receive black or white signal under AV or PC mode, adjusting brightness and contrast to set the brightness to 5 Nit in dark area and 90 Nit in bright area.
- Adjust white balance.
- Enter factory menu, select User RGB Menu
Adjust | B-R | 0-63 | default | 32 |
B-G | 0-63 | default | 32 | |
B-B | 0-63 | default | 32 | |
C-R | 0-205 | default | 128 | |
C-G | 0-205 | default | 128 | |
C-B | 0-205 | default | 128 |
Adjusting chromaticity coordinates of black and white to fit the requirement (X=0.285, Y=0.293), or plug automatic calibration system to adjust white calibration automatically.