What hot wire for drop-down screen/DVD player?

[SparkyTX]

I started installing my drop-down screen and DVD player last night. I got a wiring harness put together and all the wires pulled. Tonight I will be securing the screen and splicing into the hot wire. Question is, which hot wire?

I ran a power feed from the player and screen up under the dash near the hood release handle. The first question is should I splice into a always hot wire or an ignition hot? I like the previous, but am afraid of what would happen if one of the kids didn't turn the units off. Of course, I cuold run the wire through a "master" switch up near the dash that would give me a safety "over-ride", so to speak.

What would you guys recommend, always hot with a swich? Or ignition circuit only? And which actual wire should I look at tapping?

Or... should I use a three-way switch (ON-OFF-ON) that can power the unit off of either ignition or always hot power feeds?!?

Decisions, decisions! What are y'all's thoughts? I want to wire this tonight.

[andrewfessler]

If it was me I would wire it off of either iginition hot wire, or the same wire that allows the radio to still work for 5-10 minutes after you power the truck off.

Since most of our trucks have dual batteries, they should be able to handle without a problem the DVD player and screen without running the system battery down during the time the radio still works while ignition if off. Keep in mind once the doors open, it will shut off anyways.

I know if I was to use a master swtich, i'd prolly forget about it and it would eventually never be used.

The other option would be to possibly pull the power from the overhead spot lights in the overhead console, however, I dont know what they are rated for in regards to amperage. I think that if you leave those lights on too long, the truck turns em off for u. I think its longer than 10 minutes though . .

My .02 worth.

[SparkyTX]

Is the auto-power off of the radio controlled by the onboard computer (hence the power going to the radio) or the radio itself?

That sounds like a good idea, but then again, it has its drawbacks. I am mostly considering road trips with the kids. If they are watching a movie and I stop to get gas, when I turn off the rig, the movie stops. If I wire into the radio circuit, it would still stop after I opened the door.

The rear spot light circuit may be an option. The DVD player and the screen together draw VERY low amperage. That is not expected to be an issue.

[andrewfessler]

Sounds like then you could just use the hot wire for the overhead lights without a problem. I'd prolly still put a fuse between the lights and your DVD screen just incase something happens to the unit.

The RAP power is controller by the onboard computer, because it includes the power windows as well. GM calls it the Remote Accessory Power (RAP) feature.

The other circuits, dome lights, reading lights and underhood light, will automatically shut off after 10 minutes of being on without the truck running, I believe this is also controlled by the computer, sounds like this is the best way...If you were worried about pulling to much on the circuit, you could always use a relay setup. If u need help on that, there is post elsewhere on the forum for using a relay setup with running board lights. Same concept would apply here.

[SparkyTX]

Thanks for all the thoughts; I got it wired last night.

After all the discussion, I ended up wiring to al always hot circuit through a switch. I wired a simple SPST illuminated switch from Radio Shack on the dash between the 12V power jack and the cigarette lighter. I also drew the power and ground from that same circuit. Made for nice, clean wiring. The switch is not obtrusive, but it is obvious when it is on as it is the only illuminated thing in that area.

I ditched the ideas of the circuitry that has the auto shut-off because I really didn't want it to auto shut-off. One of the big reasons I didn't want to use the ignition circuit is that I didn't want the DVD system to shut-down when I stop to pump gas on a long road trip. For the same reason, I didn't want to use the RAP circuitry. What if I pump gas, knock around stretching my legs a little, go to the potty, and get tied up in line to pay? 10 minutes could easily go by and the system would shut-off on the kids watching.

I will post some pics when everything is completed. Everything was going great until I got the 9-pin mini-DIN connector for the screen out-of-round. Then broke off one of the connectors when trying to fix it. So tonight is dedicated to soldering on a new plug! Got to have this done for the road trip tomorrow!!!

Thanks y'all!