Cont:
- If no evidence found:
- Does Vs & Va voltages stay up.
- If yes, Panel is defective.
- If No, in this case neither PWB can be confirmed as fault. Suspect Y-SUSTAIN PWB.
- Disconnect the SDR Upper or Lower or Both from the Y-SUSTAIN PWB, and test Vs/Va voltages. They must come On and stay up with these PWBs removed from the Y-SUSTAIN PWB.
IF THERE IS NO Vs/Va
- There must be a dead load on the line, or no Vsago/Vcego commands from teh Logic PWB CN68.
- Check the Va and Vs run-on commands.
- The SBY 5V from CN63 pin-1, must be present before Vsago/Vcego lines can function. AS the Power button is pressed, [Vcc5.1V] should come when Vcego/Vsago. Commands go high.
TESTING THE Vs & Va TURN ON COMMANDS
- Press the Master Power Switch on the bottom, to remove AC.
- Wait unitl a relay click is heard.
- Unplug CN68 connector, and re-plug it back. If this is not done, Turn On command Vcego / Vasgo at pins 7&8 of CN 68 will not happen.
- Connect a DC voltmeter to the CN68 connector Vcego / Vsago.
- Press the vacation switch to apply AC power, and wait for about 30 seconds for initilization.
- If Normal: After several seconds, Vcego / Vsago voltages should reach to 3.3v.
- If a troubele is sensed, these pins will climb and then quickly drop the voltage to less than 0.03.
AFTER A TROUBLE SENSE
- Pull the CN64 connector.
- If the condition changes as described above, there is a load on Va/Vs lines.
- If the condition does not change, the the problem is with Logic PWB. Carefully examine the connector from CN68 to the Logic PWB CN6
- Look for any visible damage to this cable.
- Confirm SBY +5V from pin-1 of CN63. There are no diagnostic LED on the Digi-Main PWB.
SOME POINTS TO NOTE WITH DW-3 POWER SUPPLY
- Generates standby 5V any time AC is applied to the power supply PWB. No matter whether the set is turned On or Off.
- Digi-main PWB generates Power-1 and Power-2 commands on the CN63 connector when the set is in quick start, even when the set is Off and when the set is turned On.
- Generates all voltages of CNPPS connector, when the set is in quick start, because of Power-1 and Power-2 are high. # The TV turns on quickly. ## No data communication have to be re-initiated at turn on. ### The Sub-Digital PWB digital tuner can be on.
- Power-1 and Power-2 CN63 connector do not turn on Vs & Va or Vcc 5.1V, it only turns on the CNPPS voltages.
- Power-1 and power-2 CN68 connector comes from the Digi-Main PWB PPM1 connector.
- Vsago&Vsego CN 68 connector comes from the Logic PWB CN6 connector.
- The CN68 connector should be unplugged and then re-inserted to reset the power supply, if Vs of Va did not come up for any reason. If this is not done, Vcego / Vsago will never attempt to turn on Va/Vs again. If AC is removed, this will reset the power supply. It will take over five minutes time.
- Power supply can be forced On to test all power supplies.
- Vcc 5.1V at CN64 pin-3 and CN68 pin-1 is generated at the power supply and is output voltage from the power supply, and not an input.
- In Series-1 models, CNPPS pins7,13,14,15 all are tied together.
- In Series-2 models, CNPSS pins 13,14,15 are tied together.
- Vcc 5.1V, CN63 Pin-3 and CN68 pin-9 are tied together.
- Power-3 is not used [CN63 connector]
- The relays, RL001 & RL002 turn on any time AC is applied to power supply PWB; if quick start is Off, both relays turns off after a two minutes when AC is first applied. If quick start is on, both relays stay on. When the set is turned on, both relays turn on.
End
