[JoeBecker]

Modifed: So the thread probably won't make sense, sorry.
Several other members have noted that I was making it too complicated. Here is what I am going to do now.

The camera draws very little current and the rear wipers aren't used all the time.
The monitor will be on the 12v outlet, but I hardly ever use it (I use the 120v more often).

Better?

Thanks for all the input so far guys.

 

[jepstr67]

I've been using that reversifying glass what hangs from the front window.


Looks cool Joe. Keep us posted on the progress. I have always wanted to hook one up as a trailer hitch aid.

 

[JoeBecker]

I've been using that reversifying glass what hangs from the front window.

Is that what that shiny thing is for? :doh:

 

[Randoo-N-CJ]

I've been using that reversifying glass what hangs from the front window.

OMG..that sounded just like George Dubya speak!!!

 

[jack.allwardt]

I see a couple of flaws in your schematic...why do you think you need resistors?

The +12 v that powers the relay needs to return to ground, not in series with the intended original circuit. I'm not sure you need the relay, just "tap" a ign live fuse with a "piggy-back" one, where you remove one fuse, insert the piggyback cartridge, plug the original fuse on one leg, and your new circuit on the other. See AutoZone for these fuse units--they're around $6--and also get a new fuse--a 1 amp should work just fine. Remember: a fuse is supposed to protect the WIRING not the device.


What is the voltage of the camera and monitor components? You can calculate this based on the old formula W(wattage) = I(current) * E(voltage) If you solve these equations, you'll see that both components are 12v, and in my estimation, no resistors are required.

Questions to jack@exeterlions.org

 

[festerw]

^^ I agree, you don't need any resistors. You can use a relay but for the amount of amperage it will draw you should be able to directly wire it.

If it was me tap the wire + wire going to the power outlet stick a switch on the line to the camera and call it a day

 

[jepstr67]

OMG..that sounded just like George Dubya speak!!!

I had been watching some Beverly Hillbillies last week. Jethro always call the mirror that. Him, and Cletus from the Simpsons.

 

[JoeBecker]

The +12 v that powers the relay needs to return to ground, not in series with the intended original circuit.

Oops, I thought it could be inline (cut the original circuit and reconnect to the relay). Will correct that on the drawing.

I see a couple of flaws in your schematic...why do you think you need resistors?
What is the voltage of the camera and monitor components? You can calculate this based on the old formula W(wattage) = I(current) * E(voltage) If you solve these equations, you'll see that both components are 12v, and in my estimation, no resistors are required.

The voltage required for the two components is 12V.
I thought I need resistors because of the other basic equation E (or V as I learned it)=IR (Voltage=Current*Resistance). If the monitor is to only receive 750mA then its branch circuit must have enough resistance to limit the current draw (if reistance is "small" the current is "big"). Now, if the monitor has an internal parallel circuit with sufficient resistance to limit the current then I would not need the resistors in the main branch because the monitor will not receive the full current (wouldn't be 12A because of wire resistance but would be too much for the monitor)???

This is why I needed to ask people who know, thanks.

 

[zbee]

simplest method i found was to jumper off one of the reversing light wires to a relay, simple and effecient

 

[JoeBecker]

simplest method i found was to jumper off one of the reversing light wires to a relay, simple and effecient

So you have put one in?
Can you sketch up what you did please?

 

[zbee]

hmmm...easier to describe, used anode from lamp to relay coil, cathode to body. so when reverse light energized activated relay, tapped 12 volts off charge anode off rechargeable torch in rear interior light to power cam(an alternative source is the trailer power curcuit hidden behind the grommet), monitor also ran from same curcuit, more than enuf current to power up aswell...mind you now i have the mygig setup had to rewire as mygig senses from canbus...ill take some pics at the same time i do the mygig stuff for the knowledge base

 

[DrugRunR]

problem is that he said that he wanted to use the camera as a rearview mirror all the time, not just for when he backs up.

If you haven't modified your lighter circuit you could pull your power from it
It will have more then enough for your .8 amp circuit.
Also, why are you using res's on your ground side of your devices?
Are your devices not 12V?
You are making this ALOT more harder then it needs to be.

 

[JoeBecker]

I modified the wiring diagram in the first post based on all of your suggestions.

When I got home from work I took the lift gate apart. It was pretty easy, as long as you can get over the fear that you will snap the plastic cover and trim.
Here is what I plan to do with the camera:
I am probably going to cut a hole in the plastic bar toward the passenger side (right side) to receive the camera.

I will line it up with the hole in the sheetmetal (covered by a clear piece of vinyl to keep water out) on the right side. This way I don't have to cut into the sheetmetal.

I will connect to the wiring for the wiper motor, the video signal will follow the wire bundle route back into the body, down in a cavity that leads to the driver side taillight, out through that grommet, down under the body and up to the front (don't want to have to take stuff apart between back and front in the cabin). Have not figured out where it reenters the cabin yet.

 

[JoeBecker]

melted wiring

tested camera and monitor...
the camera wiring proceeded to short out. monitor worked fine.
here are pictures...

it melted through the rubber wire cover (bottom of picture) several wires were no longer connected because the transistor (?) melted

close up of ?

red and bare copper at top were +12v and ground attached to circuit via scotch locks.
other wires all "internal", there is continuity between white and black on camera side, and outside of rca with ground wire

fixable???? anybody know how humpty dumpty goes back together?