Ok, I cant find the constant power wire in my car, i dont know witch one it is. I need to know, that way my stereo keeps its memory. If anyone could let me know that would be nice, I see in othere places when i searched witch wires but I dont know witch one Is the constant source. Thanks for help

 

If its an aftermarket stereo, it should be yellow.

 

I dont mean the stereo, I mean in the car it self, the cars wire, witch one is the constant

 

 

I need to know the colors of the wires, because I have no harnesses

 

Blue with red stripe?


-Ted

 

These are for S4, S5 is probably the same:

Constant power - Blue wire with a red stripe
Switched power - Blue wire with a white stripe
Antenna - Blue wire with a yellow stripe (need relay)
Illumination - Red wire with a black stripe

Run new speaker wires.

 

the easiest way to find power (ony any car) is to use a 12volt test light. get one at an autoparts store for a few bucks and it will be your best friend.

use it like so:
clamp the clip end to a known ground (like the chasis) and poke the sharp end of the light into any suspect wire (making sure to pierce the insulation and touch copper). if the test light lights up (with the car off and the key out), then you know you've got a constant +12v supply. this should go to your stereo's memory.

if you find a wire that lights up only when the key is on or on accessory, then you've found keyed power, etc.

the test light also works in reverse: clamp the clip onto a known +12v source (like that wire your just found, or the + battery terminal), and stick the sharp end into a suspect wire. if it lights up, that means you've stuck a ground wire. test this by touching the chasis (which should be ground).

zatonic, this will give you indisputable results for YOUR car. I always use a light to test for power, even if I have a schematic right in front of me.

 

That method is not recommended for testing wires unless you know for sure that the wire is running to ground.

For example if you did that and probed the red/black behind the radio, the test light would light up.

Because the red/black is the dash lights and they rest at ground if they are not on.

So can you use that red/black for the ground wire on your radio??? Only when the dash lights are not on, and even then you are back feeding the switch. Of course as soon as you turn the dash lights on, the wire looses ground and the radio would stop working. Hopefully you wouldn't burn out your light switch when that happens.

Seen too many blown light switch dimmers, and messed up radio installs from micky mouse installers and less than educated DIY'rs, than I can count on my fingers and toes because of test lights improperly used.

Or what about trying that same thing with the clamp end of the (shudder) test light on 12 volts and you probe a grn/yellow in the passengers kick panel... now you just burnt up a injector and the ECU.

Only micky mouse uses a test light that way. Use a digital multi-meter when testing wires in a car.