Stereo Wiring questions

[danpluso]

Hey guys! I just bought a new head unit (Alpine CDE-102) and had a few questions about the wiring. My car is a 1997 Corolla and the previous owner cut out the head unit plug so I am stuck with wiring it to bare wires.

1. The Black (Ground) and Yellow (12V+ power) are a bit thicker then the corollas stock ground and power wires. The ground wire from the alpine unit also has a connector on the end of it to attach it under a screw. So my question is will it be alright to just wire it up to the corollas stock ground and power wires or do I have to make new connection to power and ground?

2. My other question is in regards to the corollas stock wiring. I have found different info on which wires are for what and I am confused and unsure of which one I should follow.

As you can see with these two links:
http://www.**********s.com/supra/stereodiagram.gif
http://pad.wikihow.com/images/thumb/..._table_649.PNG
They say the ground wire is black and there is no illumination wire listed.
But according to here:
http://www.modifiedlife.com/car-ster...oyota-corolla/
The ground wire is brown and the radio illumination is green. Which one should I listen to?? I wired up a sony head unit not too long ago and I am pretty sure I wired the black ground wire to the stock corolla ground wire (which was black) and everything worked fine. That was some cheap old Sony head unit. I now have a brand new Alpine CDE-102 head unit so I don't want to just wire it up and take my chances. I would like to know for sure. Brown or Black??

3. My next question is about the illumination wire. My Alpine head unit has a wire that receives a single wen the headlights are turned on so the head unit can auto dim the display on it. Which wire is the illumination wire and is there a way I can test it? Maybe use a multimeter with the black end connected to ground and the red one connected to the suspected illumination wire and then turn the headlights on? I'm am thinking that would work. Again according to the other diagram (that says ground is brown) it says the illumination wire is Green however I don't think I trust that diagram so much because I am pretty sure the ground wire is indeed black. Also every electrical thing I have ever done has always had the ground wire as black.

[Bitter]

goto a junkyard and cut a stock harness with clip off another car thats the same as yours, then just match colors and voila! back to stock and you can use plug and play harness kits.

[danpluso]

I thought of doing that just not sure if I want to go through the hassle of trying to track down a corolla at a junk yard and then having to dish out more money for the harness and harness adapter. Yeah I'm cheap that way.

I was just out in my car testing a bunch of wires with the multimeter and I have found out almost everything I need to know. I guess I should of just did that in the first place instead of making this post.The ground wire is defiantly not black and I am not sure what color it is because I am slightly color blind. I guess it is safe to say it is brown. Also found the illumination wire by using the multimeter and testing the wire with the headlights off and the headlights on.

I am still wondering about question one though in regards to the wire gauge.

[cipher93]

Corollas are a dime a dozen are junk yards, not to mention there are other connectors from other Toyota's you can use that are the same as the Corolla's, though I don't know which models these are. And seriously, a junk yard will probably only want $5 or something for an obscure part like that, and if your confused, it's for the better.

It will also be easier as these cars were made before there was an ISO standard for wire colors in car stereo's, so it can get confusing if you don't use a harness as the colors on the car's stock wires will be different than the ones on your new head unit.

[gold94corolla]

I can't find Corollas in the junkyard LOL..... they're Toyota.... they are still on the road!

[cipher93]

Originally Posted by gold94corolla

I can't find Corollas in the junkyard LOL..... they're Toyota.... they are still on the road!

Junkyard one here has 3 7th Gen Corollas and 2 Prizms. The other has like 7 Corollas I know of and like 4 or 5 Prisms somewhere else on the lot. How do I know this? Of all of those, only one had a rear view mirror and interior door handle worth a crap

[gold94corolla]

LOL.... says something about drivers up there I guess!

[danpluso]

Okay thanks for the advice but do you guys have any info on the different gauge of wire on the head unit versus the smaller gauge stock wire used in the corolla? Is it going to be okay wiring the thicker ground and power wires from the head unit to the smaller stock power and ground wires in the corolla? Is enough current going to able to get pulled through the stock corolla cables?

[cipher93]

Originally Posted by danpluso

Okay thanks for the advice but do you guys have any info on the different gauge of wire on the head unit versus the smaller gauge stock wire used in the corolla? Is it going to be okay wiring the thicker ground and power wires from the head unit to the smaller stock power and ground wires in the corolla? Is enough current going to able to get pulled through the stock corolla cables?

Not going to be an issue. The stock cables are fine for just a head unit.

LOL.... says something about drivers up there I guess!

Actually, I think only one or two were wrecked. I know I pulled my mirror from one that was destroyed when it hit a pole and flipped. Drivers side front was punched into all the way to the center console. Most of them blew out, transmissions (lot of people here blow them out towing stuff, or burn them up when they get stuck in the snow/mud), were too expensive to bring up to emissions/inspection standards, or were junked due to rust. The two yards I keep mainly strip the wrecked cars, and stock the yards with intact vehicles so you can actually find some nice projects and parts.

[danpluso]

Okay thanks. I will take a look at the local junk yard and see if I can spot me some corollas. If not I will just wire it up with out the harness.

[Asteroid]

For all the effort of buying an original plug, wiring it in then buying an adaptor harness you might as well just wire the Alpine one in. Don't worry about the difference in cable size, the factory wiring is a little on the light side for modern head units but it will work okay. As for the ground just connect the ground from the Alpine harness to the metal frame of the dash - I used one of the screws that held the head unit bracket in.

I can't help with the colour codes as it's been a while since I had mine, but a bit of probing with a multimeter or test light should find it.

[danpluso]

Originally Posted by Asteroid

For all the effort of buying an original plug, wiring it in then buying an adaptor harness you might as well just wire the Alpine one in. Don't worry about the difference in cable size, the factory wiring is a little on the light side for modern head units but it will work okay. As for the ground just connect the ground from the Alpine harness to the metal frame of the dash - I used one of the screws that held the head unit bracket in.

I can't help with the colour codes as it's been a while since I had mine, but a bit of probing with a multimeter or test light should find it.

Yeah I guess you are right about the waist of effort to get the harness. I'll just wire it in without the harness, just need to get me some heat-shrink tubing.

Is it worth the effort in mounting the ground wire to one of the screws when I can just wire it to the stock ground wire?

[Asteroid]

Either will work fine, do whatever is easier for you.

[gold94corolla]

Yeah, you can ground it to the wires.... and the difference in thickness (gage) doesn't matter!