Samsung LN40C650 “failing” with black vertical stripes (SOLVED)

Correct Diagnosis

  • Faulty seating on HDMI1 affects video arriving from HDMI4.

See Configuration and Specification below.


  • Reseat HDMI1 (independent input from TiVo).
  • See the signal from HDMI4 (the Xbox) clear up.


  • HDMI1, HDMI2, HDMI3 are all “horizontal”.
  • Connections into these sockets have a tendancy to “droop” and place pressure on the female side of the connector.
  • Unless the inbound connector and wire is supported, the force of gravity, over time, will cause these connections to become loose and failure prone.
  • HDMI4 is “vertical” and will have less of this effect.


These are barely acceptable when they are black.  When they become white, the display is unwatchable.


  • The behavior commenced after The Focus Group rerouted some video inputs and then replace them “as they were before.” See History below.
  • The behavior occurs independent of any video input signal; with no input video signal.
  • It occurs even in “Self Diagnosis” mode where the TV exhibits its own internally-supplied image.
  • There has been no internal intervention (never opened up the back).
  • The device has been mounted on a wall and cannot be jostled or insulted. But see History below.

Did you reboot?

Well, first of all, the display devices don’t run Windows, they run Linux. Rebooting isn’t generally remediatory for anything. But of course, I did a hard powercycle and replugged the power cables.


  • The behavior occurs without a video signal => it’s not an HDMI decode issue.
  • Tough to believe that internal cables became spontaneously unseated.


  • Recently, The Focus Group decided to experiment with daisy chaining the video signal as Comast->TiVo->XBox->Samsung to give XBox One the pride of place
  • That’s the product vision/promise/aspiration for the XBox One: “The One Box for the living room” (think: as with the Windows monopoly; one ring to rule them all).
  • Of course this failed.
    • XBox One can’t control the DVR features of the TiVo.
    • XBox One can barely redisplay the live TV;
      It can redisplay a signal only if it’s previously decoded with the CableCARD that’s in the TiVo.
    • XBox One can’t play recorded programs or direct the TiVo to run its applications.
  • Thus, the XBox One, again, stands alone feeding HDMI to the Master Display. It is the Master Display that rules them all; as that is what provides ultimate the value.


What are the chances that during this plugging, unplugging, replugging of HDMI cables, that some aspect of the HDMI male/female seating in HDMI1 through HDMI3 became loose enough?


  • Run (ahem) daily 8+ hours with sporadic intermissions.
  • Purchased 2013-08-01 (TV is 3.5 years old)



Samsung Series 6, Model L40C650; User Manual; 60 pages (10MB, huge)

But what did “the net” say?  Anything helpful? [tl;dr => Not really]

Consensus Diagnosis

  • The LCD is failing => it is not fixable, throw out the unit.
  • The LCD builds of that era were low quality and/or had low lifespan anyway.
  • Samsung makes “cheap TVs” and this is the best that can be hoped for, or something like that.


  • Rly? => TVs should last “a decade” or so; that’s a problem that the TV vendors are actively trying to deal with … that people buy cars more often than they buy a new TV.
  • ahem => Isn’t it the case that the “cheapie TV makers” just buy their parts from Samsung’s remainders, not the other way around?

Alternate Diagnosis

From random prattle on the forums; it’s fixable, but …

  • It’s some fuse, caused by a “voltage surge.”
  • It’s some (internal) “tab” connecting to the LCD.
  • It’s some (internal) ribbon cable that as come loose.
  • It’s a “T-Con” board (every poster spells & abbreviates this part name differently).
  • It’s a firmware issue.
  • It’s an HDMI decode issue => replug the cables, powercycle (these were perilously close to correct)


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