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When a Plasma TV is plugged in, there is a few indications of normal operation.
- There is a 'click' from the relays RL402 & RL403, when they are activated.
- The LED in the optical jack inside the 'DT' board turns ON for ~ 4 seconds.
- Immediately after that, one of the Tuner LEDs {Right} turns ON; solid Red, for ~ 20 seconds.
- The LED in the optical jack inside the 'DT' board turns ON again for ~ 1 second, and both LEDs; the tuner and the optical jack; turn OFF.
- Then an other click will be there from the relays RL402 & RL403 indicating that they are no-longer engaged. At this time, tuner and optical jack LED turn OFF.
CAUSES FOR SHUT DOWN.
- A short circuit on any of the voltage lines.
- An over-voltage condition.
- Abnormality in the Control Drive Pulse circut {SC, SU, SD & SS board}.
- Missing source voltage to the PA board. STB14V from the 'P' board.
- missing output voltage from the 'PA' board to the 'DG' board.
- Missing 15V of VSUS on either the SS or SC boards while the control drive pulses from D board are being provided.
'PA' VOLTAGE OUTPUT {BLOCK DIAGRAM]
- If any of the SUB or MAIN voltages that are high-lighted on the 'DG' board is missing, the unit goes to shut down. The power LED blinks TEN times.
- If any of the voltages created on the 'PA' board is excessive or shorted, the unit goes to shut down. The Power LED blinks 10 times.
SHUT DOWN DUE TO OVER VOLTAGE OR SHORT CIRCUIT.
- The base of [Q5642] being low indicates a short circuit in the { Main 1.8V, Main 9V or Main 5V output of the 'PA' board.
- The base of [Q5641] being low, indiates a short circuit on over-voltage condition in the NR14V, Main 1.8V, Main 3.3V, Sub 9V or Sub 5V of the 'PA' baord.
PA SOS detect circuit
P-A Board_loss of Sub-voltage.
PA Board _ Over Voltage Protection.
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