How to Replace a BMW CD Changer

1. Disconnect the negative battery cable from the BMW battery. The cable is black and connects the negative lead post to the frame of the vehicle. Use a 10-millimeter wrench to loosen the bolt on the negative cable's clamp. Remove the cable from the area of the negative lead post.
2. Remove the center dash panel (containing vents) with a trim pry tool. Start at the bottom edge and pry around the edges until the panel is free. Disconnect the power wire connected to the hazard light button to completely remove the panel.
3. Remove the two screws holding the lower trim panel (containing the climate control knobs) in place. The screws are located at the top corners of the panel, and can be removed with a Phillips-head screwdriver. Pull the lower dash panel from the stereo face. The panel will still be connected for the purpose of climate control. Leave the wires connected and place the panel to the side, out of your way.
4. Remove the two screws on either side of the BMW stereo unit, with a Phillips-head screwdriver. Slide the stereo deck forward to access the connecting wires in the rear.
5. Disconnect the patch cables from the rear of the stereo. The patch cables are attached to the stereo and branch near the outlets, turning one cable into two (like a 'Y'). Connect the patch cables to the stereo. Feed the new patch cables from the stereo to the location of the CD changer along the same route as the old cables.
6. Remove the old CD changer and replace it with the new unit. If the new changer doesn't fit in the dash, then place it in the trunk. Run the patch cables to the rear of the BMW beneath the carpeting. Use a trim pry tool to remove the panels in the doorways that secure the carpeting to the floor. Replace the panels by hand with a moderate amount of force once the cables have been laid. Attach the patch cables to the new multi-disc changer.
7. Replace the stereo in the dash of the BMW and replace the two screws on either side, using a Phillips-head screwdriver. Place the lower dash panel in place and replace the two screws at the top corners. Connect the power supply to the hazard switch of the upper dash panel, and then replace it by hand in the dash. Place the top on first, then apply pressure along the perimeter on both sides to fully lock in the panel.
8. Reconnect the negative battery cable to the negative lead of the BMW battery. Place the clamp around the negative battery lead post. Tighten the clamp with a 10-millimeter wrench.