riofrio

I thought I'd make this a new thread, since the new questions are kinda different than the others. Basically, I want to install a new receiver (with CD player) and just got the wiring harness in the mail (Scosche). I know that I need to switch around some of the wires on the power harness (the one that looks like two eyes and a mouth). With a multimeter I found that the right eye is constant negative, and the mouth is negative on ignition, but have no idea what the left eye is (power antenna?).

What's the difference between using a metal ground and using the negative battery terminal? I found that one of the power wires for the stereo shows connectivity with the negative battery terminal only when the key is in 'acc', which would be ideal... should I not use this as my ground for some reason? If not, how can I have the stereo work conditionally upon 'acc'?

I'm gonna run wire from the back of the receiver to the storage bins in order to connect to the speaker wires. What's a good path to run these wires through? I was thinking out from the sides of the stereo panel and under the carpet along inner side of both seats.

Thanks dudes.

Hades12

I would not use the Ground that you are finding when in ACC. That is Just Wrong. Metal Ground and Neg Bat is really the same. If you are running new Speaker wires then just dont use the Scosche wiring you got. All you have to do is connect the +12 on the player to the batt through a fuse. Ground to a screw in the dash. +12 switched to any switched source. Then run your new speaker wire under the drive seat. along the driver side of the car to the driver speaker and then take the wire for the pass side around the back of the car. Hide the wires for the front speaker under the carpet or up in the dash.

Misthael

You should always run your radio/cd player power and ground wires straight off the battery as well as amp power and ground wires. The only head unit wire that won't go to the battery is the accessory power wire which will need to be connected to a wire that's hot when the key is in the accessory position which I'm sure you all ready knew. I would run the signal wires behind the carpet and down the sides of the car under the carpet. It's easy to do. Just take the door sills out and the carpet lifts up enough to pu the wire in htere. I have two an external amp for my mids and I run the signal wires the same place just in the opposite direction. If you have an external amp at the back you can run the power wires down the middle under the console which you can remove by taking out a few screws. To run the head unit power and ground wires to the battery you will have to drill a hole int het firewall. All the hoel son mine were used. I just drilled a hole near where the accellerator cable came through. You can get rubber grommets to keep the wire from being shorted at any automotive store liek Autozone or O'Reilly's. I can get some pics if you would like.

enigma32

I'm with these two about the ground-- chassis ground == battery negative.

Also, yes, one of the wires in that 3-wire plug is for the power antenna...
If I recall correctly, I can hook up my testlight between it and ground and the antenna moves when the key is in the run position (possibly in Acc, too)

Good luck

riofrio

Why would that be wrong, though?

Pele

iTrader: (28)

Your stereo will turn off when you turn on your headlights...

The one that looks like two eyes and a mouth. (The 3 pin connector) contains Ignition power, Power Antenna, and ILLUMINATION... Flip on your headlights and watch that ground turn into +12v...

Use a metal ground. The stock radio does.

I've also NEVER heard of a ground ONLY when the key is in ACC... I dunno what wires you're probing... It's wrong because you're gonna loose all your radio presets, clock, and other memory stored things (CD won't restart where you left off) when you turn the key off... You need a constant +12v and a constant ground.

What you should have is a 3 pin as above and a single for CONSTANT +12v.

Speakers are a bit harder as they vary from model to model. Speakers are 4 pin square connectors. If you have the joystick fader controller in the center, don't bother looking for them in the dash. They're connected to the amps under the storage bins... Look there, extend the wires.

riofrio

Wow, thanks Pele, that makes a lot of sense now.


So do you remember which one is which? Oh, and, what are the standard wire colors on aftermarket receivers? (I know red='+', black=gnd, yellow=ignition, and speakers are easy to identify... but what about power antenna and illumination?)

The one that I thought was negative upon ignition was the mouth of the connector. I used a multimeter to test for connectivity between that terminal and the negative batt terminal and I got the beep only when the key was on ignition. Maybe it's just a coincidence.

Hades12

What he said.



And I generaly run new Larger wiring all the way.

bizarro

iTrader: (1)

IIRC power antenna is the blue wire...

riofrio

So... does anyone remember which terminals of the connector (i.e., two eyes and a mouth) correspond to what? Is the mouth ignition power?

bizarro

iTrader: (1)

once i got a cheap voltmeter from radioshack the job got simpler...i don't remember exactly...i just remember in order for it to line up i had to switch around the wires on the harness...carefull to get the connections right or else you can short out your new radio!

dblboinger

iTrader: (3)

Direct battery connections are best for stereo power connections. Theoretically the chassis is at the same potential as the battery common, but this is not always the case. When this is not true a condition know as a ground loop is the result and it can induce unwanted signals (i.e. noise) onto your audio.

enigma32

??? Not sure how one gets a ground loop when there's only one ground??

I'd agree about a direct connection to the battery (with a fuse, of course) if you're running anything but a low wattage head unit, though.

dblboinger

iTrader: (3)

Ground loops occur when two or more locations on your chassis are at a different potential. This can happen if welds are less than perfect or if metal objects, such as grounding cables bolted to your chassis or engine block, are corroded at their contact points. Each one of these will cause a resistance and current flow through that resistance can cause one location on the chassis to be at a slightly different potential than another. I've seen chassis ground connections read as much as half a volt when referenced to the negative battery terminal. So the old term "ground is ground" is NOT necessarily true.

You can avoid ground loops by either running all ground connections directly to the battery OR by selecting an easily accessible grounding spot and grounding all of your audio equipment at that point. The first is best because the second can still create a ground loop if the spot you choose is not at the same potential as your negative battery terminal. This is not to say that you have to run a separate ground wire from your battery to each piece of equipment. You can run a single large gauge cable to a good quality terminal block and then from there to each piece of equipment. This will prevent your engine compartment from becoming a spaghetti factory.

And yes, you should always use a fuse, located at the battery end of the cable, on all power wires.

mar3

iTrader: (8)

When running the power and ground wires from the battery, make sure they are on the opposite side of any low-level RCA or Uni-Link signal cables in order to eliminate that as a possible source of noise...

riofrio

Thanks for all that input, but can anyone answer my question about the 'face' connector? I just want to know if anyone recalls which terminal corresponds to what. (See attachment if you don't know which connector I'm talking about).

Pele

iTrader: (28)

www.installdr.com

There's pinouts for all cars in there... Click Quick Radio Wiring Info.

riofrio

Sweet, that's awesome. Is that looking at the embedded connector in the car, or the harness one? It also says that the 'typical new radio equivalent wire color' is yellow for '+' battery and red for ignition... i thought it was the other way around??

enigma32

I'm completely aware of this. But you don't get ground loops when there's only one ground, like with a simple head unit :-)
The ground "loop" actually occurs when there is current flowing between two different grounds, which should be equal in potential

As for what mar3 said.... if it's not possible to run power and signal lines away from each other, cross them at 90 degree angles. This will minimize the distortion caused by cross-talk.

:-)

riofrio

Alright! The CD player is in and doing its thing. Thanks to everyone who helped out!

Like I said, I payed $50 for it at a pawn shop, but spent an additional $10 for the harness and $10 for the speaker wire (I overbought!). I didnt bother to hook up the antenna, cause I never listen to the radio and didnt feel like looking for the missing connector. Now, if the Howard Stern show played in Nashville, that would have been a different story!

Anyway here's a couple of pictures of the install. I left the receiver and equalizer from the stock system just for looks, but they're obviously not hooked up. The wires are just a little visible but it's not too bad... maybe I'll hide them better some other time.

So that's it... what do you guys think?

Thanks again!!!

dblboinger

iTrader: (3)

Howard Stern???!!! He used to be pretty funny, shoulda retired while he was still on top. Want a GOOD radio talk show, check out Tom Leykis. Not in your area? Check www.blowmeuptom.com.

backofdabunny

I am still wondering why I have no antenna co-ax?I got that keyboard plug in deally.but what is that?

enigma32

The keyboard plug in dealy connects other radio stuff... like, in my '81 it connects the cassette player to the radio head, or in my '83 stereo it connects the EQ and amps to the stereo head...

bizarro

iTrader: (1)

the cd player doesn't go with the old stuff...you can easily make a pocket for it like i did...check out this thread...

Click the pic!

enigma32

I like that pocket bizarro :-)

Once I get my SE I may be doing a similar setup...
Now I just need to remember it when I'm ready to do the stereo... =P