[MarkHoff24]

Hello Bimmerfest! This my first post and I'm also new to the bimmer community. I have a 2005 325ci and I'm replacing the factory radio with a new aftermarket unit with nav, handsfree, and wifi, etc. The stereo that I purchased didn't come with installation instructions, so I've been piecing things together from this site and others. One thing that i can't seem to get correct.

How do I connect the factory speakers to the new system. I have plugged in the ISO wire harness and I guess I expected everything to work; plug and play. No so. The company I'm dealing with is in Hong Kong, so not much help. Has anyone done this before? Any suggestions? Everything else seems to work, but no sound.

Thanks for the help. Looking forward to being part of the community.

 

[tim330i]

Welcome aboard! I've moved your question to our E46 3 Series forum, you'll get more help in here. Does your new headunit have an amp integrated? Are you planning on bypassing the factory amp in the trunk?

There are a bunch of threads about this, here are two to get you started -

http://www.bimmerfest.com/forums/showthread.php?t=582702
http://forum.e46fanatics.com/showthread.php?t=1073075

 

[marcozandrini]

The car has an amp in the left side of the trunk. The primary signals between the head unit and the amp are:
- LF audio
- RF audio
- RR audio
- LR audio
- a 12VDC "turn on" signal

Please note that the audio signals between the head unit and the amp are balanced differential. The voltages for this type of signal is significantly higher than those for line level/RCA signals.