The IS300, Lexus' entry-level sedan, is equipped with an AM/FM stereo deck with built-in CD player. Owners of the IS300 who wish to replace their stock stereo unit can do so with an number of compatible aftermarket head units. Choose a single-DIN stereo deck (measuring 2 inches by 7 inches) and install it yourself to save money. Purchase the necessary wiring adapters and faceplate adapter to ensure the proper connection and fit within your Lexus' stereo mounting dock.
Lift the hood and loosen the bolt securing the negative battery cable to the negative battery terminal with a 10 mm wrench. Lift the cable from the terminal and set it aside. Move to the inside of the vehicle.
Remove the small dash panel below the stereo assembly with a trim panel removal tool. Disconnect the wiring connectors from the back of the panel and set them aside.
Remove the two bolt screws from the bottom of the stereo dock with a 10 mm socket and drive.
Remove the small access panel from the top of the dashboard above the stereo with the trim panel. Remove the two screws under the panel with a Phillips screwdriver. Grab the panel and remove it from the top of the stereo bracket.
Remove the two bolt screws from the top of the stereo bracket with the socket and drive. Pull the stereo from the stereo mounting dock. Disconnect the stereo wiring and antenna cable from the rear panel of the stock head unit.
Slide the installation sleeve (included with the new stereo) or the faceplate adapter into the stereo dock. Feed the stereo wiring and antenna cable through the back of the adapter. Connect the Lexus stereo wiring connectors to the wiring harness adapter leads.
Plug the wiring harness adapter leads into the outlets on the back of the new stereo. Plug the antenna cable into the FM antenna input on the back of the new unit. Slide the stereo into the sleeve or faceplate adapter until it snaps into place.
Place the trim panel onto the dashboard above the stereo. Screw in the two screws with the screwdriver. Place the small access panel onto the top of the dashboard above the stereo assembly and press firmly against it to snap it back into place.
Connect the wiring connectors to the back side of the thin dash panel below the stereo. Place the panel onto the dashboard and press firmly against it to snap it back onto the dashboard. Return to the Lexus' battery.
Place the negative battery cable clamp around the negative battery terminal lead. Tighten the bolt on the clamp with the wrench. Close the hood.
