Disconnect the cable from the negative battery terminal. Remove the center console. On Camry and Lexus models, use a trim tool to carefully pry the center register out from each side, disengaging the clips from the instrument panel. On Avalon models, the center register and control panel are one piece; remove the center instrument panel trim panels and use a trim tool to carefully pry the A/C Switch out from each side, disengaging the clips. Disconnect the electrical connectors and remove the assembly. If equipped, remove the audio/navigation unit and the mounting brackets from each side of the unit. Hold the audio/navigation unit and slide the A/C Switch from left to right, releasing the retaining clips. Installation is the reverse of the removal procedure. Run the engine and check for proper functioning of the heater and air conditioning.