I bought my wife a roof mount dvd player for her Tahoe. We had a cheesy portable player strapped to the head rest for our little guy. So i got a BOSS BV 11.2mc unit.
I got it all installed this morning having to fab up some stuff in the roof run the wiring etc. I found an open pin in the fuse box inside that had 12v only at key on. So i used that as my power supply.

So moment of truth, i hit the power button and it comes on ! Awesome, so all proud i drive up to the house from my shop to show the wife. She's pumped up like an inner tube !!!
So we pop a dvd in and the unit shuts off. Flipped it back on and it shut back off after 10sec. This happened numorus times before finally kicking on and staying on for 15 min or so. Really weird. So i checked all my connections and all were good.
Rode in to town and about 15 or 20 min in to our drive the player cut off and would not turn back on. Litterally like a mind of its own. So at this point I'm thinking its a faulty unit.

I get back home and start trouble shooting so when i call the manufacturer i can cover my *** when they say bad ground, or not on a good circuit etc.

Pull out the multi-meter, drop the unit enough using long bolts so it will hang enough to access the wires. I probed the hot and ground connectors at the unit KOEO. 12.3v. So i turned the unit on and it played flawless. This telling me I'm getting voltage and by probing the ground my ground is good.
So i was wondering if the pin i used for power supply at the fuse box lost power once the vehicle started, as if i got a circuit that was on a timed relay. So KOER i was getting the same voltage and the unit remained on. So with the engine running and getting 12v everything was good. I sat watching a movie engine running and watching my volt meter at the same time.
After 10 or so min the dvd player shut off ! i looked at my voltage and had 14.3v going to the dvd player. So i grabbed another meter out of my truck and checked the battery and alt and it was the same. I tried turning the unit on several times while at 14v and it would kick on for a few sec then kick back off. After 5 + min the voltage dropped to 13.2 and i decided to turn it back on. Once i hit the power button the voltage dropped to 11.9 and the unit remained on and playing until another spike in voltage.

With all that said I'm guessing her alternator sees a drop in voltage around 11.5v then kicks on and charges at 14v. The unit must have built in protection if it sees more than 13v. Kinda crummy since most charge at over 13v.
I tried looking for several other locations to tap into when the voltage was at 14v and everything i probed red the same as what the dvd player was getting. I was going to check the factory head unit supply but the skeeters were getting bad and did not want to get into ripping the dash apart.

If i cannot find a circuit or anything to tap into that stays below 13v should i get a 12v regulator and wire that in ?
Im still going to call the manufacturer and tell them the issue and see if they have any advice.

 

I would contact the manufacturer with what you describe. There should already be a diode which limits voltage on the circuit board.

Another thing, I don't tap Fuses. Find the wire you want to use (use a Wiring Diagram), make certain it is not on a circuit such as the PCM, IDM, Fuel Pump... anything that would otherwise damage your truck or damage the Unit. Cut, solder, Protect (fuse), and Weather Seal. You shouldn't have any issues until the GEM attempts to sleep (voltage wise - Key Off).

Another check, when it is ON use a DVOM to measure across the (+) on the device to a KNOWN GOOD GROUND. Whatever the difference is between that and voltage measured at the Battery is what the unit uses. The unit probably only uses 7 - 9 vdc to operate.

 

It sounds like the voltage regulator is the way to go, but what a raw deal for a vehicle unit that doesn't handle alternator voltage.

 

Sounds like there might be a safety in the DVD that may need to be grounded. Kinda like a backup camera. Check your owners manual.

 

It is possible that the unit is defective, has a poorly engineered power supply or a poorly made power supply. There should be a regulator in the power supply so that the unit only sees a constant voltage, regardless of the supply volts, within a given range.

 

I did not really tap a fuse.
The chevy tahoe has a 3 fuse boxes , 1 under the hood, 1 when you open up the drivers door and one down by the brake pedal. I read on a few tahoe forums " guys you don't know how lucky we are for FTE " and everything i read said to hook up to an open pin in the panel by the break pedal. Bottom left #3 pin. There are male exposed pins sticking out which i used a female connector to slide over it.
Everything else you mentioned is far above my pay grade lol. But i will research it and see what i can come up with.

 

Rich,
Really your not kidding ! Her car spikes 14.3 then charges around 13.6 and 13.9. I too am thinking that the regulator is the way to go. Im calling the Manufacturer tomorrow with the issue. If they cannot give me help thats my solution

 

Deluxe06 you mentioned checking the owners manuel for grounding like on a backup camera.

Well for you and the others check out the super detailed manuel they sent. Here is a link to the on line version, this is word for word what came with the unit. https://www.google.com/url?sa=t&rct=...qyi7npvVeTeflg