How to Install an Amplifier in a BMW 6

1. Disconnect the negative cable from the battery, which is located under the hood on most models. Some models house the battery in the trunk beneath the battery cover panel. Use a 10-millimeter wrench to loosen the cable clamp's bolt. Remove the clamp completely from the lead post.
2. Connect the amplifier terminal ring (included in the amplifier wiring kit) to the positive lead of the battery, using a Phillips-head screwdriver. Make sure that the fuse is removed from the terminal ring until the installation is complete.
3. Remove the vent housing panel at the top center of the dashboard, with a trim panel tool. The vent panels will still be connected via the hazard lamp wire. Pull the wire free from the hazard button to fully release the vent panel.
4. Pull the climate control panel free from the dash. Grab the panel at the bottom with both hands. Pull outward and upward to un-clip the panel. Lift the panel to release the top clips and completely remove the panel.
5. Remove the two screws on either side of the stereo unit with a Phillips-head screwdriver. Slide the stereo deck forward to access the wiring in the rear of the stereo.
6. Pull the connecting wiring groups from the rear of the stereo deck by hand (in any order). Do not pull the wires; instead, pull the plastic brackets that group the wires together.
7. Reconnect the wire groups to a wiring harness adapter. The adapter leads will be clearly marked with symbols or abbreviations to indicate where to make the connections. Connect the wiring harness adapter leads to the stereo.
8. Feed the amplifier terminal ring wire from the battery to the inside cabin of the BMW, following the path already established by the stereo unit power supply. Continue running the wire to the location of the amplifier. A common choice is in the trunk. Connect the ring terminal wire to the power input on the amplifier.
9. Connect the amplifier to the speakers you wish to amplify with speaker wires. The paths will already be established by way of the rear speakers to the stereo unit.
10. Connect the turn-on lead and signal cable to the amplifier (from the amplifier wiring kit). Run the signal cable on the opposite side of the BMW as the power supply wires and parallel to the patch cables that connect the 6-disc changer. The turn-on lead should be routed on the same side of the vehicle as the power supply. Use a trim panel tool to remove the panels at the door openings that secure the carpeting to the floor. Lay the cables beneath the carpeting and replace the panels by hand with a moderate amount of force.
11. Connect the turn-on lead and the signal cable to the wiring harness adapter.
12. Replace the stereo in the dash. Screw the two screws that hold the deck into the mounting bracket, using a Phillips-head screwdriver. Replace the climate control trim panel at the top of the dash, then push downward with equal force on both sides. Connect the power supply to the hazard lamp button and attach the vent panel to the upper dash.
13. Connect the negative battery cable to the battery. Place the cable clamp around the negative lead post. Tighten the clamp's bolt with a 10-millimeter wrench until the clamp cannot be moved around the lead by hand. Place the fuse into the amplifier ring terminal (connected to the positive battery lead).