Hey guys,
I just got a radar detector for xmas and its the kind that connects straight to a cig outlet. Now I can wire it behind the dash and all, but I don't like it taking up that spot. So, is there a way that I can clip off the cig plug and splice that wire into another 12v wire? If so, which wire do I tap it in to? Also, can I use a t-tap to make life easy? (not sure where to pick one of those up). Lastly, I want the detector to turn on with the car and turn off with the car, so that's the wire I want to tap into. Is this possible? Thanks

 

Yes you can do that. Here are the steps.

Cut off cig plug, but leave a couple inshes of wire hanging from it. The wire will either be 2 conductors side by side like speaker wire, or it will be one conductor inside another like a composite cable.

Either way, you will need to figure out which one is positve and which one is negative. If you get it backwards, it will most likely fry the radar detector.

Use a multimeter to test continuity on the piece you cut off. The wire that is connected to the center pin is the wire that will connect to your +12v. The wire that connects to the outside of the cig lighter is the ground.

Once you know which wire is which, wiring it up is simple. The ground can be connected just about anywhere. I would look for a stock bolt that goes through the sheet metal behind the dash and connect it there. A small ring terminal like this would be ideal.



For the positive wire, you could use a simple fuse tap to tap it into the fuse box. It looks like this:



You can get that at any auto parts store for about $5.

To install it, find a fuse that controls a circuit that is only on when the car is on and pull the fuse out. Put that fuse in the rear hole of the fuse tap, and a new fuse of 1 - 2 amp rating into the front hole that has the red wire coming out of it.

Connect the wire hanging off of the fuse tap to the +12v wire on the radar detector.

Insert the tap into the hole in the fuse box left by the fuse you pulled out and you are done.

 

Well alright, that doesn't sound so bad. I'll have to try it out. Wiring is not my strong suit, so hopefully i won't fry the unit! I try to simplify things as much as possible, so i'm gonna print out that post and follow step by step. Thanks for the help

 

Alright, i'm having trouble finding a fuse to tap into. Any idea which fuse would be a good one to tap into? I don't have much of the fancy equipment to help me out here.

 

I don't have a TC so I'm not sure how the fuses are labeled. I would look for something like ACC, CIG, HVAC, HTR, DFRST, etc.. Really any circuit that is turned off with the key will work. Things like headlights and brake lights won't work because they are still on with the key off.

 

the fuses are labeled as such as well... you can look inside the manual in section 8 and can see the entire listing of all the fuses, locations and each thing it's responsible for.

 

alright, so i've got everything figured out (from your guys help) except two little things. First, is there going to be a ring terminal in there already or do I need to buy one? If there isn't one, can I just wrap the wire around any other bolt connected to the chassis?
Second question, I don't have a multimeter, is there any way of figuring out which is positive/negative w/o one or do I need to go out and buy one?

Thanks guys!

 

You can wrap the ground wire around a bolt, but it will be more prone to falling off. You should be able to get a small pack of ring terminals for around a buck. It's a small investment to insure that the wire stays where you put it.

The rest of this post is a ghetto way of not using a multimeter. It will work, but is not as safe as using a meter. If you don't understand it, don't do it.

You can use a test light to figure out which wire is positive and which is negative. Even a plain 12v automotive bulb would do.

Here is how you could do it:

Before cutting the cig plug off, check to make sure you can tell the difference between the two wires coming out of it. If it is a side-by-side pair of wires, does one have a line or dots on it? etc..

Make sure the cut wires are not touching each other and plug the cut off cigarette plug into the lighter socket.

Connect one side of a light to a ground in your car.

Touch one of the two wires to the other side of the light.

If the light lights up, you have found your positive wire.

If it doesn't light, try the other wire.

If neither light, you have done something wrong.

Again, don't do this if you don't understand it, and never use this method for testing something sensative.

 

Sounds better than electricuting myself to figure it out. i'll either give that a shot or get a multimeter if not too expensive and i'll definitely pick up some ring terminals. thanks for the help!

 

Go to radioshack. They have multimeters for about 20.00 and they go up from there. Also there is a sweet write up on this in the Tech section

 

Thats an interesting write-up...a very different approach. Where would I get a t-tap though?

 

Radioshack has them as well.

 

Remember you are working with 12 volts only!


John

 

Alright, so I went out and got a multimeter, some terminals, and some t-taps. I was just thinking and tell me if this works. Can't I just use a t-tap to tap into the 2 wires from the cigarette lighter? There is a black and a white wire. I assume black is positive and the white is the ground. So after I determine which is which on my detector, can't I just hook up positive to positive and ground to ground?

Heres a pic to help explain which wires i'm talking about:

 

Black should be ground. Anytime there is black in electrical its a ground 99% of the time. Also if the wires can reach yes that would work fine to. All you need is a 12volt power source and a ground.

 

Awesome, so i'll connect the ground on the radar to the black and the positive on the radar to the white. (i'll of course use my new multimeter to double check). I plan on using t-taps to tap into each of the wires. This should be a piece of cake. I'm sure i'll be back in 10 minutes with another question! lol thanks guys

 

Ok, question;

I'm using a multimeter from radioshack which has a red and a black cable. The line from the detector is a red and white. I cut the wire from the detector and plugged in the cigarette plug with whats left of the wire exposed. When doing red to red and black to white with the multimeter, I got 12V, when doing red to white and black to red, I got a -12V reading. So, this means that the red is the positive cable and the white is the negative (ground) cable?

I'm a noobie to wiring...ya caught me

 

You are correct. Just be sure to double check the wires behind the lighter. In the xB, I'm fairly certain they are backwards. IE Black is +

 

Yep. wow am I glad that i've had your guys advice to help me with this. otherwise i wouldn't have checked. The black is indeed the positive. I almost fried the whole thing. whew. I'm just connecting everything up now and i'll be done in a few minutes (hopefully). i'll let you know how it goes.

 

is our cigarette lighter sockets always on or only on when the ignition is turned on. if it is on all the time i suggest u not use it because the radar would always be on. if it does only turn on when the ignition is on then splice the wires and ur set. if i were u i would just use an auto relay and hook it straight to the ignition wire for the radio, but thats just me.