The Lexus RX330 front and rear side marker bulbs both utilize a 168 bulb size for proper illumination. The replacement chart covers 2004 to 2006 model years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Lexus RX330 uses the 168 bulb for both front and rear side marker positions across the 2004-2006 model years.
The 168 is a miniature wedge-type bulb, classified under the T10 form factor, which refers to its tubular shape with a wedge base that requires no separate socket pins.
The 168 operates at 12 volts and draws 4.9 watts, placing it in the low-wattage range typical of marker and courtesy lighting applications.
The 168 carries ANSI standardization recognized in both the United States and Canada, meaning it conforms to a defined set of electrical and physical tolerances shared across compliant manufacturers.
Because the same bulb size applies to both the front and rear side marker positions on the Lexus RX330, a single bulb type serves all four side marker sockets on the vehicle.
The T10 wedge base is a widely used form factor in automotive lighting, and multiple bulb part numbers beyond the 168 share this base type, though wattage and voltage ratings may differ among them.
Substituting a T10-based bulb with a different wattage rating than 4.9W risks exceeding the current tolerance of the original socket, which is designed around the 168 specification.