How to Install a Non-Factory Car Radio
- 1). Disconnect the grounding cable from the vehicle's battery. Use a 10mm wrench to loosen the clamp that holds the grounding cable to the negative lead post of the vehicle's battery. Move the cable from the battery and rest it in a location to avoid premature reconnection.
- 2). Remove the factory stereo from the vehicle. Exact procedures for removing the factory stereo will vary. Consult the vehicle owner's manual for precise instructions.
- 3). Disconnect the stereo wiring connected to the back of the factory stereo. Pull the stereo wiring from the back of the stereo by the wire group binders, not by the wires themselves.
- 4). Slide a faceplate adapter into the vacant stereo mounting bracket of the vehicle. Pull the stereo wiring from the back of the stereo mounting dock to the front of the dashboard, through the faceplate adapter.
- 5). Connect the vehicle stereo wiring to a wiring harness adapter. The wiring harness adapter will be labeled to show where the appropriate connections are to be made. Connect the wiring harness adapter leads to the aftermarket stereo.
- 6). Slide the new stereo into the space provided by the faceplate adapter.
- 7). Place the grounding cable clamp onto the negative battery lead post. Tighten the clamp onto the post with the 10mm wrench.
Source...