Help me figure out this wiring (auto, best, seats, truck)

[ducviloxi]

A few years ago I had a powered subwoofer put in my truck by an installer. The wiring was done by them. The sub was stolen from my truck shortly thereafter and since then I had just left the wiring capped off (the thieves had cut off all the wires with a knife) and I did not bother to replace the sub.

Now, I am putting in another sub but I cannot figure out the wires. For the new sub I need a remote turn on lead, +/- 12V and L +-/R +- line level inputs. So in total I expect 7 or so wires. Unfortunately there are 14 wires in total here. I have:

A light blue wire with a white stripe
2 yellow wires (both do not have stripes on them)
2 black wires
1 plastic insulated wire with red and yellow thin center wires in them and a outer wire around them
5 thin wires of various colors in an insulated jacket

I have a multimeter and measured for a voltage between: both yellow wires, both black wires and both plastic wires and did not get any voltage reading.

My question is: How can I figure out which wire is which?

Now looking back I think I took the voltage with the incorrect wires. I am guessing the dual pair of yellow and black are the +/- 12V? The light blue/white stripe is the remote turn on lead and I will have to figure out which 4 wires are the Left rear +/- and Right rear +/-? Can I do this without disconnecting the head unit? i.e. possibly by measuring the resistance or something?

Now that I think more about it I am guessing the installer put in 2 power sources which explains the 2 sets of yellow/black. What confused me is when I read on the net that ground is never black and always "hot" and never used as ground...this is contrary to what I had assumed earlier which was that black is always the ground wire. Infact, the Kenwood wiring diagram lists black as the ground wire.

http://electrical.about.com/od/wirin...olorcoding.htm

[Me007gold]

light blue with stripe should be your remote wire. Thats about as far as I can help.

[reed303]

The link you list is for 120V AC house wiring, not 12V DC auto wiring.

[Billy_J]

Wire colors can be ANYTHING!

Plus automotive manufacturers regularly change wire colors for the same exact things from model year to model year!

You can't go by what color a wire is!

What you need to do is find the installation manual for your radio and/or separate amplifier and look at the wire colors coming out of those units. Then see WHAT those wires are for and what color wires they are connected to. (Assuming the installer ran new subwoofer wires to the radio and/or amplifier.)

I've frequently seen a radio installed where one color wire is coming out of the radio, then spliced to another color wire. Installers do not typically match color for color, rather they use the wire colors they have on hand.

You can also find installation manuals on a manufacturer's web site if you no longer have these.

Anyway the first thing I would do is pull out the radio from the dash and see what is connected to what. And look for a separate amplifier elsewhere in the vehicle.

Then write it down for future reference!

[NHDave]

Very simple solution, buy a multimeter and learn how to use it, color codes can be wrong, you should always verify the wiring. Seeing as you're not well versed in automotive wiring (judging by the link you provided to building wiring), if you just try to wing it you are going to fry something.

[GregW]

He already has a multimeter and apparently knows how to use it. After validating the continuity of all the wires from where they were cut off to whatever they are hooked to I suggest turning on the radio/amplifier and checking for voltage on each wire before placing a signal on any. Once the power and control wires are labled put a test disk in the player and check for AC voltage on the remaining wires by playing a Right Channel separately from a Left Channel.

Once you have figured what is where and does what take some pictures as well as writing a car specific manual. keep both somewhere safe. You do not want to do this again.

Patience is not just a virtue in this situation it is a necessity. Have fun.

[NHDave]

Originally Posted by GregW

He already has a multimeter and apparently knows how to use it.

That's what I get for posting before the morning coffee

[hoffdano]

It might help if you told us what kind of subwoofer you had previously. And what kind of headunit is in the vehicle.

In automotive wiring, black is very commonly used for ground. And blue is often the color of a turn on lead - either for a power antenna or to turn on an amplifier.

But I would not place much value on the wire color coding at all. I am not aware of any standard for car speaker wire color coding.

[Lux Hauler]

Ignore the colors, they mean nothing. Instead, label them as you figure out what each is individually. Why are you assuming the wires are still hot? They could have very well shorted out when the thieves were hacking things up. The installers would have had a fused main line from the battery, check the fuse and trace the wiring. Also when checking voltages, check everything in reference to ground... i'm assuming the sub is by your seats in a pickup, use the seat mounting hardware as ground making sure you have good contact.

Your best bet is going to be tracing the wires.

[ducviloxi]

thanks, the yellow and black was the power as I had thought. There are 2 pairs of them and the other is extra power that the installer probably wire in for good measure. The blue is remote turn on. I still have to figure out the subwoofer line inputs.

Now, a quick question...theoretically what would happen if the power wires were to somehow loosen and pop out of the amp and touch each other? (extremely unlikely to happen but just thinking of a worst case scenario).. I would imagine it could cause a fuse to blow in the vehicle's fuse box correct? I mean this power is not coming directly from the battery I would imagine?