VU Plus red led C819 and C820 short cut

Discussion in 'VuPlus Duo Hardware troubles and Repair support.' started by pnung, Oct 4, 2018.

  1. pnung

    pnung New Member

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    Hi!
    I have red led problem on my VU+ DUO genuin BOX.
    U801, C807, C814 and C850 are replaced. Voltages on F803, F812 and F813 are OK.

    My problem is a short cut to ground on C819 and C820 (poth pins of C819 and C820 are connected to GND when tested with multimeter).

    Actual I desolderd R811, U802, C819 and C820 but still both pins of C819 and both pins of C820 are connected to GND.
    Cant find C817 on your "VU+ Duo P801/5v2 informatuion" but C817 also both pins are connected to ground. JTAG Connection switch to green "connected", but can not access memory.

    Any idea what I could test?
     
  2. Johnny B.

    Johnny B. Technical Support Staff Member Moderator

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    C819 and C820
    Best way to see from which side the issue accourse is to remove the F804.
    Suppose that the C819 positive side still has a short to ground, but C820 not, then the U802 side is not the cause, the problem is from the other parts side.

    Suppose that the C819 positive side is fine, but C820 not, then it is a issue from the U802.
     
  3. pnung

    pnung New Member

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    I removed f804: now only c819 both pins are connected to gnd.
    U802 side is ok. But what can cause this gnd Problem in 819 side ?

    Kind regards.
     
  4. Johnny B.

    Johnny B. Technical Support Staff Member Moderator

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    Just as other receivers with a broadcom cpu, It's used for a voltage to the cpu.
    Still it does not have to be cause to it, it may also be a part which is connected to this circuit.

    The only thing is, I have never tried to find it out, thus I have no further information where/how this circuit goes.