1988 BMW 325ix E30 Radio Audio Wiring Diagram Schematic Colors Nov 08, 2014Here is the stereo radio wiring information for your 1988 BMW 325ix E30 with the standard or amplified systems. It will be useful when installing an aftermarket radio, sound stereo system, or other automotive accessories. Make sure to grab the appropriate tools to test all the wires in your 325i E30.Wiring Diagram · Uncategorized · Install · About E30 Stereo Wiring for Dummies - R3VLimited Forums Oct 21, 2010My lastest project is I'm trying to wire up a new stereo into my new (old) 1987 325i E30 (Premium Sound, with the fader in the dash and the amp in the trunk) Guess what? IT'S SUPER NOT EASY! I'm wiring in a Alpine CDE-100 headunit, I'm keeping the stock speakers for now. I can't use a wiring harness as they don't exist for that old car.