I'm using my cigarette lighter for an FM transmitter; need to provide power to my GPS unit. I don't want to use any splitters either..

I have a '98 Civic EX. What I'm trying to do is hard-wire the 5V line for the GPS power supply directly to the fuse box of the car. This means running the cable from the engine compartment to the interior through the air vent by the windshield. I’ve seen this done on a Mazda 3.

I could use some help with the electronics part. I’m sure people have done this for radar detectors etc..

Which fuse do I use? I looked at the fuse diagram and there’s a few unused ones. GPS requires a 5V / 1mA input. Will I need a converter of some sort to achieve this?

 

If you have the '98 civic (I have the '99) this would be the easiest way to do it. Your fuse box should have like 4 accesory slots. 2 of them supply 12v when the parking lights are turned on and other 2 whenever the key is turned to electrical or whatever. Anyways, what you can do is use an inline fuse holder, some like 10-12ga wire and female slide conects. Use a female slide connect to connect the fuse holder right to the male terminal on the accesory slot. then run it to straight to your + gps wire (you might have to splice the connecor) and ground to your - part. Instead of splycing it you could buy a 12v outlet from radioshack, run the wires to that and then mount it on a flush surface.

Anyways, thats what I'd do.

Also make sure you don't use more then like a 8.5 amp fuse. Those accesory slots can't handle more ampage that that. If you do it'll blow the next fuse in line which is the AC fuse, at least in mine.

 

I agree with ltkenbo's suggestions. What I can add to this discussion is that fuse #28 in the under-dash fuse/relay box serves both the audio unit and an optional connector (ACC) (see picture). Therefore, you could connect the 12V-5V RadioShack converter (mentioned by ltkenbo) to the optional ACC connector, if it is not already in use. This strategy has two advantages. The GPS unit will receive power only when the ignition key is turned ON, and an inline fuse would not be necessary as the 10A #28 fuse would serve this purpose.

[IMG]local://upfiles/25538/07E9CA30361247B289F95D44E28A86C1.jpg[/IMG]

 

"inline fuse holder".. I searched online.. Couldn't find anything that looks right.
If you've done this kind of thing before, where did you get the parts?

 

Done it many times You can get all the parts you need at autozone. The inline fuse holders arelike $3 at autozone. I've done a lot of car wiring, plus I'm an electrical engineering student, well only first year, but its a start, lol. Anyways, you can also get them oznium.com

They look like this:
http://www.oznium.com/atc-fuse-holder

 

Ok, I think I got the electerical part figured out then.. I'm going to be tapping into the fuse box that's under the steering wheel (not in the engine bay).

Found a nice clean illustration for the fuse tap. In line fuse is not needed.

In terms of running the wire. Shouldn't be too bad - take off the plastic under the steering wheel and by the windshield (looks like just one bolt holding it)..

[IMG]local://upfiles/5848/AD4218E3E5884137BB56020C701D7A41.jpg[/IMG]

 

One more question.. So I open up my current cigarette charger and get my positive and negative. I will be able to get the HOT terminal from the fused-side of the fuse (that way the circuitry is intact). That's one wire, but what about the GROUND? What's the best place to ground?

And I guess I better drive down to Radioshack for a 12V-5V converter..

 

Could you provide more details about what you plan to connect to what. Otherwise, you might get some bad information.

 

Hmm, guys.. Thanks for the input!

I tweaked around the plastic and it seems like it's going to be pretty tought to run a wire through the air vent - you'd have to take apart the entire dash.

GPS is powered by a mini-USB input. I get USB power from the FM Transmitter. All I need is a USB hub - one port for the thumb drive; other for GPS power. It will be cleaner w/o running any wires.

Here's my transmitter by the way - pretty simple/cool way to get MP3 into a Civic w/o changing the head unit. http://cgi.ebay.com/ws/eBayISAPI.dll...:IT&ih=012