12 Volt Key On Power Source

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Mad Max

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I wanted to mount a Garmin GPS (on the dash) and Valentine One radar detector (above rear view mirror) without wires showing or cutting/splicing into the factory wiring. I didn't want solid power, because I didn't want to have to remember to power off anything. I looked for the most convenient location to find key on power, and I also wanted an out of the way place to mount the 12v power socket.

So here we go...


I located 12v key on power near the glove box...
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Closer look...
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I traced the yellow/green-stripe wire a few inches up to a gray connector. I then took the solid yellow wire for the new 12v socket, pushed it into the connection of the yellow/green-stripe wire, and spooned both wires with a ziptie.
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Grounded to an existing bolt. Ziptied the new 12v power socket to the dash support.
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I'm putting the GPS on the dash, so I removed the tray in order to route the GPS wire under the dash. It's simple to drop your wire down into the dash after the tray is removed. When the wire is dropped down from the dash, you can reach up towards the center of the dash from the glove box opening and grab the wire.
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Valentine One above the rear-view mirror...
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Garmin GPS on the dash...
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I have a 3-into-1 "Y-adapter" plugged into the new 12v socket, so I can plug up 3 devices under there. If I need to unplug my GPS or Valentine One, or plug in a 3rd device, all I have to do is remove the passenger side dash panel (as if you were accessing your AUX wiring) and the new 12v socket and "Y-adapter" are reachable from there.

And yes I know...I currently the fuse splice connected with a wirenut. That was for ease of identifying connections for the photos. I will solder and heat shrink the connection later this evening.
 
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gwpfan

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Nice write up.

I've often wondered, but does the radar detector's view get blocked at all with the window graphics? Just thinking that would suck to have your range of that decreased drastically.
 

The Macf

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Nice write up.



I've often wondered, but does the radar detector's view get blocked at all with the window graphics? Just thinking that would suck to have your range of that decreased drastically.


I was also wondering this. Great write up to.


I need to install those headers still...
 

Tmesic

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Just out of curiousity whats the problem with a wire nut ? They use them in homes and they do the job, it is not visible, so is there an issue using them in an automotive application or is just unconventional ? Tim
 

The Car Stereo Company

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Just out of curiousity whats the problem with a wire nut ? They use them in homes and they do the job, it is not visible, so is there an issue using them in an automotive application or is just unconventional ? Tim
think of it this way, you dont take your house offroading. vibration can cause those things to fall off. that would leave you with a bare connection. but the main reason is these things were designed to be used with solid core wire. in the automotive world, we use stranded wire. twist those wire nuts enough, and you will have a lot of strands laying on the ground and a connection that is held on by a couple threads of wire. plus they ar big, bulky, and ugly.
 

mikehoncho88

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Nice write up! I set mine up almost the same. I used the same mount as you did, but I screwed it directly to the dash tray. And I ran my power lead to up fitter 3. May change that later but for now it's nice to be able to flip a switch to turn it off if I'm not using it.


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gwpfan

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think of it this way, you dont take your house offroading. vibration can cause those things to fall off. that would leave you with a bare connection. but the main reason is these things were designed to be used with solid core wire. in the automotive world, we use stranded wire. twist those wire nuts enough, and you will have a lot of strands laying on the ground and a connection that is held on by a couple threads of wire. plus they ar big, bulky, and ugly.

I agree overall, wire nuts shouldn't be used where a lot of vibration can occur. Add tape :ROFLJest: Tape will help, but it wont' solve it - solder preferred then second is crimp (where you crimp each end), third is the automotive crimp (that cuts into the insulation and is supposed to only touch the wire with the crimp) and last is wire nuts. It's amazing how driving around and screwed connections will come loose.

As to solid vs. stranded I've used a ton of wire nuts on stranded connections for motors and other such 'stationary' connections. On finer gage wire just don't He-Man the connections when you twist, make it snug and I'll even twist it enough to allow the wires to start twisting together to help. Also make sure you used the correct size wire nut. Nothing worse than a grossly oversized wire nut or undersized. By far best is solder, assuming one does a decent job soldering and leaves slack around the solder connection. To the OP nice write up but honestly your Red Wire nut is oversized, should be a Beige or Orange with tape at min. Granted it is likely your temporary connection... :D
 

goathearder

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The cigarette lighter adapter is an interesting choice, I've never thought about that before. I usually run a bus bar like this for 12v Key on Distribution:

Common 100A Mini BusBar - 5 Gang with Cover - Blue Sea Systems

Run a 8 ga wire from the battery to a relay, energize the relay with a 12v and then run another 8 ga from the relay to the bus bar. That gives you a place to hook up multiple 12v without having to splice lots of factory wires and since you are supplying power direct from the batt, you don't have to worry too much about pulling too many amps from a small 12 v key on wire.
 
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