Dead screen, no pilot light

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  • burntfingers
    Senior Member
    • Jan 2011
    • 148

    #21
    Re: Dead screen, no pilot light

    Originally posted by selldoor
    Whilst it is probably the least of your problems you say "There is also 5 volts on the standby LED, but it does not turn on." could it be that the led is just burnt out?
    Can you try another led or try and light it with external power?


    ALSO

    Also you say"I have no means of getting any station or select AV." what do you mean? I can understand no stations but have you anything you can set up - a dvd player or vcr that you know is working and can attach by scart or composite cables then even without seeing the screen . Set it going then cycle through the function buttton or remote (if you have one) to see if you can hear the sound of the dvd or tape?
    Normally, I connect my colour bar generator with sound modulation to the RF aerial input or only video to RCA plug [yellow] and go from there. But I feel no heat in the sound amplifier and assume it is not processing anything.

    I can assume that there is sound, but that doesn't help resolve the main problem.
    Last edited by burntfingers; 01-10-2012, 11:35 AM. Reason: To add last sentence.

    Comment

    • burntfingers
      Senior Member
      • Jan 2011
      • 148

      #22
      Re: Dead screen, no pilot light

      Originally posted by tom66
      I didn't notice this board is using an add-on DC-DC converter. Check the output voltages on this converter, across the main caps. They should be 5V and 3.3V. Were these the voltages you were reporting when I asked you to check 5V and 3.3V?

      Those Lelon caps could be bad, too, but I think that would cause a low supply voltage, which would be obvious. Also, Lelon seem to think copying Panasonic's T-vent is fun, they can't seem to make up their mind about whether to use an X or a three-way star.
      I did check the two voltages on the caps and they read OK.
      But I was thinking: since the lamps voltage is correct and goes its normal way to their circuit, could it be something wrong there sending a feedback pulse to shut down the set?
      On a second thought I think not, because I have actually removed the plug that takes the 24 volts to the inverters and the result is still nothing.

      Comment

      • tom66
        EVs Rule
        • Apr 2011
        • 32560
        • UK

        #23
        Re: Dead screen, no pilot light

        Originally posted by burntfingers
        I did check the two voltages on the caps and they read OK.
        But I was thinking: since the lamps voltage is correct and goes its normal way to their circuit, could it be something wrong there sending a feedback pulse to shut down the set?
        On a second thought I think not, because I have actually removed the plug that takes the 24 volts to the inverters and the result is still nothing.
        Do you have a 2.2k resistor?

        Try unplugging the inverter connector then pulling up pin #5 of PL602.
        Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
        For service manual, schematic, boardview (board view), datasheet, cad - use our search.

        Comment

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