Accessory power connection

[jbpwhatwhat]

Hi all,
I recently purchased the Audiovox FMM 100 FM Modulator so that I can hook up my iPod to my car stereo, and get the best sound possible out of the speakers. (see http://www.f-body.com/forum/showthre...ighlight=audio for more info on that)

I am trying to install this thing right now, and I kinda need some help. The only power thing I've installed on a car before were after market fog lights, and I ran them directly to the actual battery terminal, on the battery. Do I have to do that for this? I don't seen anywhere on the back of my stereo to connect this thing to 12 volt power. I also need to ground it, which shouldn't be too difficult, I just haven't found a good screw for that yet. Could I connect it to the exposed wire coming out of the back of my stereo? (is that the ground?)

Any help would be great, as I'd really like to put my car back together.

thanks a lot,
jbp

[tabahr]

You could run a wire to the fuse panel and stick it in a spot that gets power with the accessory.

Or, you could intercept the +12v switched line at the back of the radio. You could intercept a ground there also. This is most likely what I would do..

Do you have a test light or a meter to verify you are grabbing the correct wires? I would recommend having both on hand during any electrical project.

Also note, You do not have any information about what year, make or model car you are working on. If you had that information in your signature, helping you would be easier. We might even be able to provide pictures of your exact application.

[hotwhip9]

If you don't use your cigarette lighter you can use those leads for both hot and ground. Finding a ground is not that hard, there are many decent places to ground to under the kick plate, or you may be able to get in the ground wire of the stereo. You can tap into the fuse box for your hotlead, or run a new wire with some inline fuses on both ends of course from the battery, or get a 3 way adapter and tap into the lighters hot lead. In any case make sure you use fuses and if possible put it on a switch. I think thats a personal preference of mine, i love switches. I have my accessory power, for the blacklights on a switch in the dash, next to the camaro emblem. Fuse box is usually the safest way to go, although I find it difficult to do. Make sure you disconnect the battery when wiring all this stuff though, just to be on the safe side.

[jbpwhatwhat]

Thank you for both of your input. I do use my lighter a lot, so I can't take the leads from that. If I were to tap into the lighter leads, I might as well just tap into the stereo's leads. Would I really need a voltage detector or anything? It seems that the red and black wire on the back of the stereo should make it obvious as to what they represent. Am I wrong about that?

thanks again
jbp

p.s. Now I am starting to wonder about the space for a switch next to the camaro emblem and the fog light switch. There are wires going to that non-existent switch. Are those hot? Any ideas on that?

[tabahr]

Originally posted by jbpwhatwhat
Would I really need a voltage detector or anything? It seems that the red and black wire on the back of the stereo should make it obvious as to what they represent.

p.s. Now I am starting to wonder about the space for a switch next to the camaro emblem and the fog light switch. There are wires going to that non-existent switch. Are those hot? Any ideas on that?

The radio has 2 hot leads. One is +12v BAT and the other is +12v ACC. I think the colors are usually red & yellow. I'd use a testlight to double check which is which.

As far as the wires behind the non-existant switch... Another chance to use your test light.

Test lights are cheap, I'd recommend buying one if you don't have one already. A couple bucks worth of tools can make all the difference sometimes.

[Injuneer]

Maybe I missed it, but you might want to mention what year F-Body you have. The 4th Gens, for example, have connections in the end-of-dash fuse panel for both "switched" and "unswitched" fuse-protected +12V power. I use the switched (marked "IGN") for my gauges and nitrous system. The connections are accessed simply by using a crimp on male spade lug.

[jbpwhatwhat]

wow, I didn't know I could use that box on the dash. Mine is 4th generation too. So thats a 12 volt accessory? thats the one I need? Is there a ground on there too that I can use? Honestly, I really dont know what you mean by "switched" and "unswitched" unless you are referring to the toggle switch for the device, because I do have one of those. Do you know if the bare wire coming out of the back of the stereo is the ground wire?

thank you for any answer you might have.

jbp

[Injuneer]

"Switched" means the +12V power is only available when the ignition switch (key) is in the "on" position. "Unswitched" means the +12V power is always available at the source, even when the key is switched off.

To establish a "ground", all you do is run a wire to any screw or bolt that is into the sheet metal under the dash, crimp a terminal on the end of your ground wire and put the terminal under the screw or bolt.

The device you are talking about adding to your car appears to be a low power eletronic load. By using the power from the fuse panel at the end of the dash, you will be protected by a fuse, and will not risk overloading the circuit.

You can also just "splice" into the cigarette lighter +12V wire.... I have my ScanMaster powered off that source. The cigarette lighter circuit is "unswitched", so your device will remain on when the ignition key is "off".

Camaros (but not Firebirds) also have a "hidden" power source under the center of the dash. Rob/Shoebox has information about it on his "tech pages" website.

Don't know what the wires look like for the stock stereo.... I don't have any system at all in my car..... .