HELP NEEDED: Hard Wiring a 12v DC Connection

Hi - I would like to start by saying that I am not an electrician and I am freaked about attempting this.

I want to hardwire two 12V DC Connections for my Radar Detector and external GPS System.

I havethis cable (http://www.amazon.com/gp/product/B001A4HAQ2/) for hardwiring the GPS; andthis cable (http://www.amazon.com/gp/product/B000WQF21Y/) for hardwiring the radar detector.

I was told that simply tapping into the back of cigarette lighter is not a good idea since I might blow a fuse if I overload the circuit.

On this video (http://www.youtube.com/watch?v=ALj_c42sCbk) in you tube, it shows that I can tap into an empty fuse slot in order to hardwire a 12v connection.


SO FINALLY -
Has anyone actually done a connection like this from the fuse box?

If so can you give me some hints?

Does anyone know which empty fuse slot turns off when the ignition comes off?

Thank you for any help! :)

Jaded,

I did this for my nuvi 680. All wiring tucked out of sight. Used a switchable fuse post so that car on, power on; car off, power off. Good luck!

http://www.ridgelineownersclub.com/forums/showthread.php?t=26255

I noticed you're using dedicated hard wiring connections (per your amazon links). I used the supplied ac power adapter that plugs into the cig lighter power plugs.

Thanks for the info! However, the fuse tap that you suggested does not work in an 09 Ridgeline. You need to get a mini fuse tap (http://www.parts-express.com/pe/showdetl.cfm?Partnumber=071-585)! Thanks for the DIY though!

Those taps are very handy and make a clean installation. I've always just flattened the stranded wire out a little then shoved it into the load side of the fuse slot, then inserted the fuse to hold it tight.

It's kinda hacky electrical work, it's just something I've been doing for so many years that it sticks. But from now on I'm going to use those taps picture above.

Hi e_piph_a_ny! I have a quick question. There are only two empty fuse sockets in the 09 Interior Fuse Panel. I want to set up my Radar Detector and GPS to turn on only when the car is on (as you described when using fuse slot 29 in your post).

Can you help me figure out which fuse slot to use? (see Pic for Fuse Panel and it's uses on the 09).

I was thinking of tapping fuse slot 9 which is the rear accessory slot and hooking up both the GPS and the radar detector to one fuse tap. What do you think?

I used slot 11 on my 2009 RT. It's the wipers, switched by the ignition, and it's out of the way (on the far corner) so that tap won't block anything.

Slot 29 doesn't appear to be switched by the ignition, could that have changed for 2009?

Thanks for the tip SteelCity! I tried slot 11 and Eureka - it works! I am guessing any fuse lots labeled IG XXXX are ignition slots? That way they only are powered when the ignition is on. I also used the same tap to draw power for my GPS.

Do you think that having two devices tapped into one slot will be an issue (electrical wise?)

I will post a DIY as soon as I pull down the dash (tomorrow) and run the wires properly!

Lastly, e_piph_a_ny did you protect your wires running through the AC vent with any thermal tubing?? If not has it been an issue in the winter when the heat is on?

Thanks to both e_piph_a_ny and Steel City for all the help!

Depending on where these items are going to be located, it's actually quite easy to tap off the back of one of the 12v outlets. I can't find the pictures I took of the jumper I made, and I'm too lazy to go pull the lower dash to take new ones but it's a simple setup.

If you pull the lower center console and look at the back of one of the power outlets, you'll see that they use a standard spade connection that is built into the stock connector. A trip to Auto Zone or Radio Shack to pick up some 1/4" male and female spade connectors. With these it was a simple job making a short jumper to place between the truck's connector and the outlet. This jumper has a tie in for the power to my gps.

Do you think that having two devices tapped into one slot will be an issue (electrical wise?)


The amount of devices doesn't matter, the total current draw does. A GPS and a Radar Detector draw very little current so you will be ok.

The amount of devices doesn't matter, the total current draw does. A GPS and a Radar Detector draw very little current so you will be ok.

That's why I couldn't figure out why the OP didn't just tap off the front (switched) power outlets, since all that takes is a couple of 1/4" spade lug connectors... (I have a 3-outlet "extender" hardwired throught the front outlets & have had no overloading issues running 2 phone chargers, a GPS & a 100W inverter powering a laptop off those outlets...)

Depending on where these items are going to be located, it's actually quite easy to tap off the back of one of the 12v outlets. I can't find the pictures I took of the jumper I made, and I'm too lazy to go pull the lower dash to take new ones but it's a simple setup.

If you pull the lower center console and look at the back of one of the power outlets, you'll see that they use a standard spade connection that is built into the stock connector. A trip to Auto Zone or Radio Shack to pick up some 1/4" male and female spade connectors. With these it was a simple job making a short jumper to place between the truck's connector and the outlet. This jumper has a tie in for the power to my gps.
You're definitely correct about using the power ports when your devices are close by. I saw pictures of the way you guys spliced a tail and used the spade connectors, good idea. However, I have always had luck with simple taps:
http://di1.shopping.com/images/pi/c2/62/3d/70584806-100x100-0-0.jpg

Some people don't like them, but they have proven themselves to me. I installed 6 rows of cove lights about 240 foot long each in a mall food court. The lights were 4' long end to end the entire way, instead of splicing with wirenuts the whole way I pulled one set of wires down thru every light, the entire 240 foot. I then went back to each light and used a brown 3M Tap in each light.

After wiring all 360 lights with these taps (3 times as fast as conventional splicing) I turned it on and every light worked. To this day my company still has that mall as an account and not one tap connection has come loose.

So I'm definitely a believer.

That's why I couldn't figure out why the OP didn't just tap off the front (switched) power outlets, since all that takes is a couple of 1/4" spade lug connectors... (I have a 3-outlet "extender" hardwired throught the front outlets & have had no overloading issues running 2 phone chargers, a GPS & a 100W inverter powering a laptop off those outlets...)

From what I gather in the first post, someone told him it wasn't a good idea. I'd disagree with that person.

I just installed my GPS last week and I went to the fuse box too, but only because the GPS is mounted on the top left side of the windshield and the fuse box was directly below it and very accessible.

Wire taps have their place, in my experience a vehicle is not one of them. That mall food court doesn't move (thus no vibration) and is climate controlled (no moisture issues). This can't be said about a moving vehicle. Wire taps in a vehicle can work themselves loose, and result in electrical gremlins.

The use of an add a fuse is a great way to access switched power without permanently altering the vehicles wiring. I've used them on cars and motorcycles with no issues. I only offered up tapping the rear of the outlets as another option for someone that wants to add accessories in the vicinity of the 12v outlets.

Wire taps have their place, in my experience a vehicle is not one of them. That mall food court doesn't move (thus no vibration) and is climate controlled (no moisture issues). This can't be said about a moving vehicle. Wire taps in a vehicle can work themselves loose, and result in electrical gremlins.


The exact same thing could be said for a spade connection.

Like I said, your mileage may vary, but I would trust a quality tap just as much as any other connection.

Lastly, e_piph_a_ny did you protect your wires running through the AC vent with any thermal tubing?? If not has it been an issue in the winter when the heat is on?

Thanks to both e_piph_a_ny and Steel City for all the help!
The gps power cable is pretty sturdy for my 680. But you need to consider that I live in the SoCal area and rarely use the heater. If it's a concern, I would insulate it just to err on the side of caution.

Good Luck!