How to Make an AUX Input on a Factory Radio
- 1). Lift the vehicle's hood and loosen the bolt holding the negative battery cable clamp to the negative battery terminal with a wrench. Remove the cable from the battery and set it aside. Move to the inside of the vehicle.
- 2). Remove the radio from the vehicle's stereo mounting dock. Consult the vehicle repair manual for instructions specific to the removal of your vehicle's stereo unit.
- 3). Disconnect the stereo wiring connectors from the outlets on the back of the head unit. Check for release mechanisms on your vehicle's connectors. Pulling the cables from the outlets without squeezing the release can permanently damage the connector.
- 4). Connect the stereo wiring connectors to the wiring harness adapter leads. The adapter will bridge the gap in compatibility between your vehicle's stereo wiring and the FM modulator that will be used to establish the AUX input.
- 5). Plug the wiring harness adapter lead connectors to the FM modulator inputs. Plug the FM modulator wiring connectors into the corresponding outlets on the rear panel of the factory radio.
- 6). Feed the FM modulator input lead into the storage pocket below the stereo dock or into the adjacent glove compartment. Either location will suffice; not all vehicles have an opening to a storage pocket.
- 7). Place the FM modulator box in the back of the vehicle's stereo dock. Replace the radio in the mounting dock. Replace any dash panels that were removed as instructed by the repair manual. Return to the vehicle's engine compartment.
- 8). Place the negative battery cable clamp back on the negative battery terminal post. Tighten the bolt on the cable with the wrench. Close the vehicle's hood.
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