How to Install an Aftermarket Deck on a BMW E46
- 1). Lift the BMW's hood. Loosen the bolt securing the grounding cable to the negative battery terminal with an adjustable wrench or pair of pliers. Lift the cable from the battery terminal and set it aside.
- 2). Wrap a thin cloth shop rag over the blade of a trim panel removal tool to protect the finish of the BMW's dashboard. Pry the thin trim panel from the dashboard. Start above the glove compartment and work your way to the left until the panel is completely removed.
- 3). Remove the two screws at the top corners of the factory stereo with a Phillips head screwdriver. Slide the unit from the dashboard far enough to access the stereo wiring and antenna cables connected to the back of the stereo.
- 4). Disconnect the two stereo wiring connectors from the outlets on the factory stereo's rear panel. Unplug the antenna cable lead from the back of the stock unit. Set the stereo aside.
- 5). Slide the aftermarket stereo faceplate adapter into the BMW's empty stereo mounting dock. Push the plastic sleeve into the dock until it snaps into place. Pull the E46's stereo wiring and antenna cables from the back of the dock to the front of the dashboard.
- 6). Plug the stereo wiring connectors into the wiring harness adapter leads. Consult the wiring harness adapter's manual for precise connection locations. Some adapters will be labeled or color-coded to show the proper connection sequence.
- 7). Plug the wiring harness adapter lead connectors into the appropriate outlets on the back of the aftermarket deck. Insert the antenna cable lead into the FM/AM antenna input on the new stereo's rear panel.
- 8). Slide the stereo into the faceplate adapter. Push the aftermarket deck into the dashboard until it locks into place inside the stereo mounting dock. Replace the thin trim panel above the stereo assembly. Press firmly across the length of the panel until it snaps back into place on the dashboard.
- 9). Replace the grounding cable clamp around the negative battery terminal. Tighten the bolt on the cable's clamp with the wrench or pliers. Close the BMW's hood.
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