OK, here goes....had dealer install "Factory" Invision Dual Headrest DVD players when we purchased GMC Yukon new in 2008. Had years of trouble-free service. Then my daughter broke one of the buttons and I managed to glue it a time or two until that no longer worked. That was the "A" unit. Then the screen was almost pulled down on the B unit, so with both giving problems I ordered a set from a guy on Ebay. His "A" unit has worked flawlessly. I am on my third "B" unit, however. I am beginning to wonder if the problem isn't with the wiring inside the seat. My saving grace is that both units I've sent back to him have shown the same issues I had when he tried them out, which appears to be more of a "unit" problem than wiring to the unit.

The symptom now, with this third player is that I can connect the two plugs that go into the unit with my Yukon running, and it powers up and will turn on and work flawlessly. I can power it on and off, no problem. But if I turn the vehicle off and then restart it, the Power button lights up but the unit will not turn on. I can disconnect the unit, re-connect it, and it will power up and work again.

Needless to say, I can't very well re-install the unit every time I start the vehicle. I'm not sure how these things are installed...I'm guessing a central "box" or "brain" and wiring harnesses to each unit from there. Does anyone have a good guess or recognize what I'm describing? This is maddening! The dealership admits they are not a car electronics store and have limited troubleshooting ability. The local car stereo shops dismissed me, told me to try my "A" unit in the "B" unit slot and if it worked then I should know the problem is the 'B" unit and not the wiring. When I asked for a screwdriver to try that I was told "no loaning of tools" and that their labor rate was $60/hour....both of which seem fine, but not when said in the same breath.

Hints? Suggestions? Remedies?