Radio Install power source

[wolds]

I'm getting ready to install a new radio in my car to replace the old after market radio. The previous install was questionable and I'm trying to figure out where the radio sources its 12VDC and power for memory from. I looked in my Bentley, but I don't see a reference to the radio in it. I figure I'd piggieback the memory 12VDC off the clock and I could take the source 12VDC off the light switch, but I'd just as soon wire this as the factory did. Any suggestions?

[schumicat]

host site has factory wiring diagrams which will tell you wire colors for power/switched power than run to radio. but like you say you can just get it from any available source.

[Andy911sc]

There should already be wires down there. Get yourself a voltmeter and set it to the chirp mode when power is detected. Make sure you have a good ground and some gator clips, so you can do it hands free. Ground wire is obviously the brown. Speaker wires are obvious also. Just see which one has power without the key in and make sure the other has power on/off with the key to on position. No need to start the car. I might have some close up pictures on my thread

[wolds]

Thanks for the info guys.

[Andy911sc]

I have confidence in you. Just take your time and if you are unsure, post some pics. We will try and point you in the right direction. I used to do custom stereo installations back in high school as a side business. That money got me through my first year of college loan free.

[Nickshu]

There should be a yellow w/ red stripe wire that is 12v+ for the radio in there somewhere. HOWEVER your wire may be red, from reading old threads there seems to be some variation here on different 911's with no real consistency, some have radio wires that are yellow/red and some have solid red.

The ground wire (brown) runs across from the MPIII ground area which runs together w/ the headlight switch harness and grounds in the frunk, just forward of the back of the fuel/oil gauge.

This may help:

Which one of these is the Factory Radio/Stereo Ground Wire?

Good luck!

[wolds]

Thanks, I just printed off the wiring diagram from the host. Looks like the radio gets 12VDC from the ignition switch and should be a yellow wire if I'm interpreting this right.

[nineball]

typically constant is yellow and switched is red but you never know what you are getting into when someone else has "worked" on it before. your best bet is a multimeter and a beer

[Andy911sc]

Originally Posted by nineball

typically constant is yellow and switched is red but you never know what you are getting into when someone else has "worked" on it before. your best bet is a multimeter and a beer

best advice ever.... Multimeter and a BEER! and if you get stuck another BEER wouldn't hurt. I know I downed a few when I was working on mine.

[wolds]

How much beer?

[nineball]

Originally Posted by wolds

How much beer?

enough

[nettles503]

Originally Posted by nineball

enough

No such thing.

[nineball]

of course there is, i just haven't reached that point yet. still trying though, especially on the weekends.

[Nickshu]

Originally Posted by wolds

Thanks, I just printed off the wiring diagram from the host. Looks like the radio gets 12VDC from the ignition switch and should be a yellow wire if I'm interpreting this right.

Oh sorry, It's either solid Yellow or Yellow w/ red stripe.

Not RED as I said above....my memory failed me!

[wolds]

10-4, I'll grab a beer and my DVM tomorrow and go look, right after I clean my windshield channel in preparation for the windshield install next week.