mySAVIOReigns

I am getting my wiring ready to put in a cd player (or cd/mp3, or fm tuner or whatever). I want to get my wiring ready before I put it all in, but I’m a little lost. Here’s what I have:

CD Player will have a switched power lead, a battery lead, and a ground lead (among other things) + Battery to

6-gang auxiliary fuse block.
Fuse block to #30 on relay


#30 (yellow) battery lead on CD
#85 on the relay would be grounded
#86 needs to be power from the ignition
#87 would go to the (red) switched power lead on the CD player

Problem is, I’m not sure where to pull #86 from. Would I have to splice into the stock wiring system to get the switched ignition? If so, where is the best place to?
So basically what I’m getting at is, I would like to use all new wires so as not to blow my old and decrepit ones

Oh yea, and I just realized I missed one. Where would the (yellow) battery lead on the CD player go to? I don't want to clutter up the engine bay by running it to the battery, but if I need to then I guess I will.

TexasAxMan

Why are you using a relay to wire in a radio?

Using a test light just probe wires until you find a constant power and a switched power wire. That and a ground is all you need. Just make sure the insulation on the wires you use is still pliable.

mySAVIOReigns

I've always heard that you should never try to do that, because it's 40 years old, and I don't want to catch fire.

At least, it will give me peace of mind...

oh, and the relay is because I want to pull some more juice to run it

jlg2002

You can get your batt hot 12 v from the yellow wire circuit that feeds the cigar lighter. The switched 12 volts can come from the blue-red wire that feeds the fuse block. Also, they make little clips that go between the fuse and the fuse holder to tap off of for voltage. If not, your only means is to use a splice of some kind.

PS: a relay is overkill for a radio (and most everything else except for high power consumption devices).
good luck

mySAVIOReigns

Gotcha...

Hmph, I thought the relay would be necessary. Oh well awesome, thanks for the help.

jlg2002

Don't get me wrong, relays have a place on car electrical systems, typically they power a power amp or foglights or something that needs higher amperage to work correctly. You can certainly use one for your radio, but it then creates a little more circuit complexity than is really needed.

67 evil eleanor

Don't be so sure that a relay is not necessary. The power reqirementsshould be listed on the unit (or instructions) and will determine the wire size and fuse you will need for the supply circuit (and ground wire size). Some amps are built in to thehead unit,and these can require 20 to 40 amps or more to operate, sometimes more that the lighter circuit canhandle.A properly sized and fused relayis necessary to supply the current to operate the system.If the wire size is too small, and the fuse too large, then enough heat can occur to cause a fire (20 amp fuse on a run of 22 gauge wire). Best advice is to meet the reqirements of the unit(s).

noroof66

Tap the wires right onto the fuse block. If you do not want to pull it and go behind, you can get some adapters to snap under the fuse and use a female spade connector on your stereo wire. Go right to the stereo and sig lighter fuses, at the box. Be sure to use the fuse on your stereo and go to the triggered side of the fuse box (side that does not work if fuse is removed). This way you have double protection. Evil Eleanor is correct about the relay and larger current. If you need more than 20 amps, I would highly recommend running a wire to the battery.

ninteen66mustang

In the way of finding wires, I just installed a tach, and to find all the different wires that (direct to battery, hot with ignition, etc.) I just crawled under the dash and kept testing things till I found an open connector that did what I wanted... Your wiring may not be the same cuz the ppl that had it before me installed a bunch of crap for the alarm and stuff.

JMD

You can also get a "fresh" switched power supply from the center terminal of the ignition switch. All you need to do is to attach a hoop to the wire and screw a new nut on the center post to "piggyback" the new supply wire. you should run an inline fuse also of course.

Quick, painless and absolutly no cutting or splicing.

(the terminal I am speaping of is a stud that extends from dead center of the switch, the only one with a threaded terminal.)