3-Series (E21, E30)Chat relating to the BMW 3-Series from 1975-1983 and 1984-1991 line. Specific models: BMW 315, BMW 316, BMW 318, BMW 318i, BMW 320/4, BMW 320i, BMW 320/6, BMW 323i, BMW 320i. E30 Family models include: BMW 325e, BMW 325i, BMW 325is, BMW 325ix.
When i got my car, the wiring was so funky in it, i dindt even know what to think. well, i am finally getting a stereo for it on wednesday, and i was going through all the wirng and finding what was what. well, i found everything, except the ground, or at least i think i have it but im nto sure. i found to wires that tested as good grounds. one is a brown wire all by itself, the other is i think gray and red(or brown) and it runs to a plug, connected wiht the constant hot wire, is this one the ground? also, where is the auto antenna wire? or what is a way i could find it? any help would be great, or a wiring diagram for the stereos in this car(84 318i). Thanks. Chris---
my car had 3 grounds, prem sound, all brown with black stripe. i snipped the two small ones and used the largest of the three. if in doubt, just run a new ground. the main grounding point is located under the steering column, you need to remove the knee bolster to access it. the grey/red is definately not a ground.
ant should be a white wire, mine had two spliced together.
OK, ill check for the white wire. I spent an hour last night searching for wire diagrams, and i couldnt find anyhting. but i also suck at searching for things, so i could jsut put the wrong thing in or since i was scimming the ones that sounded good, i may have missed one. but thanks. Chris---
OK, jsut checked my car and there is no white wire up with all the other stereo wires. and if the gray/red wire is not ground, what is it? how come it tests as a good ground every time. whats it for? thanks Chris---
Your gonna probably want to rewire all the speakers. Does your car have a fader switch in the dash? If so the your system has a common ground.
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
oh man,i forgot to tell you if it works or not. sorry. well it works and i just ran my own speaker wire and my own ground, and kept the ignition wire and constant hot. thanks froi everybodies help. Chris---
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