Wiring a toggle switch to the 12V outlet?

darthroush · Post by **darthroush** » Sat Nov 27, 2010 5:09 pm

What would be the best way to wire in a toggle switch to the outlet so it would have constant power when the switch was on, and behave as normal when the switch was off? I would like second opinions before I start cutting wires.

TheRandom1 · Post by **TheRandom1** » Sat Nov 27, 2010 6:07 pm

By using a light switch?

darthroush · Post by **darthroush** » Sat Nov 27, 2010 6:16 pm

Clever.

TheRandom1 · Post by **TheRandom1** » Sat Nov 27, 2010 6:17 pm

I'm serious... I don't get what exactly the question is. You cut the wire leading to the outlet, install a light switch in the cut and go. Am I missing something?

darthroush · Post by **darthroush** » Sat Nov 27, 2010 6:26 pm

I don't want the power to come on and off with a switch; the ignition switch does that already. I want to be able to have power to the outlet whenever I would like, whether the car is on or not.

[Yes, I get the light switch jokes. Very nice.]

TheRandom1 · Post by **TheRandom1** » Sat Nov 27, 2010 6:42 pm

Oh you mean actually in the car. Why the hell would you want that?

I wasn't making any jokes actually...

Post by **occasional demons** » Sat Nov 27, 2010 7:15 pm

You need a fused power source to the switch or relay, spliced into the (+) wire.

Use the toggle to power a relay that has a normally closed contact, and a normally open. Use the normally open for the ign circuit, and the normally closed for the ign off (+) source. This way the relay coil isn't drawing power with the engine off. While it may not be much, it all adds up.

If you don't want to mess with a relay, a switch and a diode could be used, but both will need to handle the amperage you are putting through them. Otherwise they may get hot/melt things.

ZeroChad · Post by **ZeroChad** » Sat Nov 27, 2010 9:40 pm

So basically you just want to be able to bypass the ignition controlled power. Use a 3 prong switch with NO, NC, and common contacts.
Step 1. Connect the common to the positive side of your outlet.
Step 2. Connect the NC to the normal power wire.
Step 3.Connect the NO to your new fused always on ciruict.
Step 4. ???
Step 5. Profit.

You'll probably have a momentary lose of power to the outlet when you flip the switch doing it that way, but you don't need to worry about a diode. The other way you can do it is so:
Step 1. Create fused constant power line.
Step 2. Run this circuit through a 2 prong switch and splice it into the positive side of the outlet.
Step 3. Cut the normal power wire and install a diode 'upstream' of where you spliced in the new circuit.

darthroush · Post by **darthroush** » Sun Nov 28, 2010 2:42 am

TheRandom1 wrote:Oh you mean actually in the car. Why the hell would you want that?

I wasn't making any jokes actually...

So that way I can charge my phone/Ipod/whatever without having to have the cars ignition on. I can plug it in and leave it locked in the car.

Thanks for the tips guys! I was missing a piece to the puzzle; I just have to decide if I want to go with a relay or the 3 prong switch/fuse. I have no idea what a diode is or what it is for, so I will keep it more simple for me.

Should I use a fuse rated the same as the current fuse for the outlet?

Pablodragon · Post by **Pablodragon** » Sun Nov 28, 2010 1:08 pm

why not just re-wire it to be always on?

it doesn't use any battery if nothing is plugged into it...

any when the car is running, or the ignition switch is on...the alaways on plug is STILL on...

so why would you ever want to switch it back to being controlled by the ignition switch?

(the only thing I can think of is, say, you have like a GPS... but you gonna have to unplug that when you turn the car off to plug in yer Ipod to charge it anyway)

darthroush · Post by **darthroush** » Sun Nov 28, 2010 5:04 pm

I thought about it; I suppose I could. The Neon is the only car I own that doesn't have an "always on" outlet. It doesn't matter much to me either way.

Post by **occasional demons** » Sun Nov 28, 2010 5:28 pm

The diode was so the power from the non ign. source would not feed back to the switch. While it shouldn't power the ign. switch controlled stuff with the key off, I only mentioned it in case it would.

I thought about ZeroChad's common/two outs too, but again, I didn't know what you were powering. If just charging/running an ipod/cell, the switch should be adequate. But say a 12v air compressor, or power inverter, might melt a switch.

What I did for my Zune/GPS was do a 5 volt power supply, and dual USB outlets. I put the switch in the console storage to turn the 5v supply on/off. I store the USB cable(s) in the console storage when not in use.

This is where I mounted the USB outlets, but they could be mounted inside the console storage for security, if you were to leave something in the car to charge.

I also have a remote IR receiver in there for my Zune Dock, so I can just use the remote while driving, instead of trying to mess with the MP3.

Most cell phones use less than 1 amp to charge, so it isn't going to kill your battery doing it this way. My daughter has left her cell in the car to charge all day, and it hasn't even made a dent in cranking power. I can't say that about the plug in cell chargers. I have had to jump a few ppl at work, that forgot to unplug them at lunchtime. Not sure what those things draw, but damn.

darthroush · Post by **darthroush** » Sun Nov 28, 2010 6:18 pm

I've left a cell phone plugged in, in my Mustang for a couple of days and cranking was not affected at all. I wanted be able to leave it "normal" as it came on the car in case I decided to use a power inverter or something, in which the car should be running anyways.

darthroush · Post by **darthroush** » Thu Jan 06, 2011 6:37 pm

I bought an add-a-circuit (I'm just going to cut the wire and hook it directly to an always on source) , but the packaging says it is only good for 10A? Couldn't I just put a 20A fuse in it? The add-a-circuit has 16AWG wire, which is good for 20A up to 10', isn't it?

Post by **occasional demons** » Fri Jan 07, 2011 9:51 am

You could solder a wire to a 20 amp fuse, and slide it in like so, using an empty slot,

or source a fuse box and pull the wires from it to run an oem looking set up.

Pics from viewtopic.php?t=50819

I think the 10 amp limit is more for the oem fuse box, because you are loading the circuit with two fuses/loads.

darthroush · Post by **darthroush** » Fri Jan 07, 2011 3:03 pm

Hmm. I guess I'll take the AAC back (good point about the 10A limit). Sounds easy enough though; I've got the little clips that allow you to just slide a connector onto the fuse.

Mopar00Neon · Post by **Mopar00Neon** » Sun Jan 30, 2011 2:11 pm

I ran a fused lead directly from the battery, to a distribution block behind the useless cubby hole in the dash, (also did a ground dist. block), and wired in switches and LEDs. I wont get into all of my wiring, as there are some relays and varrious other things going on back there.

The switches obviously have power all the time, as they are connected directly to the battery. These switches power my export rear fog lights, trunk lighting, interior lighting, exterior lighting, and another power source for phone chargers/iPods/laptops/USB/etc. (thats the one with some extras going on in the wiring). The OEM plug is left alone, and I really never use it. I get too annoyed with it being off when the car is off.

I have left phones/iPods charging for up to days at a time on the one switch (the one in the on position in the pic).. along with the LED indicator above the switch, and have never had a problem with starting or draining the battery. Ive even used a small power inverter to run a laptop for about an hour or so, and the car still started right up.

darthroush · Post by **darthroush** » Tue Apr 19, 2011 11:16 pm

I finally did this, and another electrical "project" today.

For the 12V outlet, I picked up an in-line fuse holder and connected it to the extra 12G wire coming off of my positive battery cable; 20A fuse just like normal. From there, I ran 12G to the outlet and connected it in place. I cut the factory wire back in case it needs to be changed back later. Works beautifully.

My other project was to "soft-hardwire" my GPS. I didn't just buy a hardwire kit as I've got a traffic receiving power cord. I bought the add-a-fuse mini and added it to a 12V switched fuse. The add-a-fuse got a 5A fuse. A new 12V outlet was wired to that inside the fuse panel access area, so the outlet and my GPS power cable are both out of sight. I ran the excess power cable under the dash pad (which as far as I can tell already, has greatly improved it's reception capability vs. hanging down onto the floorboard) and ran the connector up through the opening by the window for the VIN plate.