what is "rewiring"

[bmwannabe]

i know im a retard, but what does rewiring entail, and why do it?

[DanGillan]

it means running all new speaker wire from your head unit to your speakers (or anything in between (crossovers etc.)) it's not very hard, just time consuming.

[bmwannabe]

why do it, just for better performance or what?

[UNHCLL]

why do it, just for better performance or what?

BMW uses a common ground stereo system. On early cars, there are only 2 channels, Front and Rear. You want to be able to send individual signals to each speaker when you add a new HU, so thats why you rewire.

[Jordan]

why do it, just for better performance or what?

BMW uses a common ground stereo system. On early cars, there are only 2 channels, Front and Rear. You want to be able to send individual signals to each speaker when you add a new HU, so thats why you rewire.

Also, if you attempt to power your speakers with an aftermarket headunit without rewiring you will burnout the output stage of the headunits built in amp and completely destroy the headunit.

[DrMcDave]

i wired my with cross overs and 3 way speakers and it took about 10 hours of work. I had to modify the 5.25 inch speaker holes to fit 6.5's as well as cut the door card to fit the 4 inch speakers, then you have to deal with teh stupid tweeter. Also finding good places for the cross overs is a pain. The worst part was wiring from the body to the door. I need to work on that tomorrow and seal it all up.

[StereoInstaller1]

To clarify a bit on what UNHCLL said, BMW non-amplified cars have a fader in the dash. Wiring from the deck to the fader is "common sided" ground, meaning 1 ground wire for both left speakers, 1 for right. This is ONLY between the deck and the fader. All bimmers have seperate grounds between the fader and the speakers, but the junction of the wires is a bit down the harness, and has traditionally been wrapped with the nasty sticky black cloth tape that those bavarian freeks seem to just love. If you pull the fader out of the dash, you will be able to follow the harness back a bit (under the IP comes to mind, but my mind is slippery) to find the junction of all 8 speaker wires plus the wiring from the deck. The reason you pretty much have to do this is because todays decks require all 8 speaker wires (2 wires per speaker, right?) to come all the way to the deck if you want maximum power. Almost all of todays decks have 4 channel amps on board but due to the type of design, they cannot share a ground anywhere.
HTH,
Luke
Oh, and BTW, it is just sometimes easier to run your own wires from the deck to the speakers. I can use the stock wires quicker, and if they aren't oxidized, I am OK with that. Good Luck!
Luke

[sweetride01]

why do it, just for better performance or what?

BMW uses a common ground stereo system. On early cars, there are only 2 channels, Front and Rear. You want to be able to send individual signals to each speaker when you add a new HU, so thats why you rewire.

Also, if you attempt to power your speakers with an aftermarket headunit without rewiring you will burnout the output stage of the headunits built in amp and completely destroy the headunit.

My car had a Clarion headunit when I got it. Does this mean that it has already been rewired?

[BMW BMXER]

My car had an aftermarket Kenwood in it, I took it out and had my current deck put in.

The factory fader is still wired in and still works..

I dont get it.

[DanGillan]

you dont HAVE to do it, I installed my aftermarket deck without re-wiring, but it's a good idea, you will get better clarity and less distortion if you re-wire with a good quality wire.

[BMW BMXER]

Ya, I keep meaning to rewire mine because it acts up everyonce and awhile.