INFINITI M45 Back Up Light Bulb Size

The INFINITI M45 back up light utilizes a 921 bulb size for illumination purposes within the rear housing assembly. Data provided covers a span from 2003 through 2010 for the specified vehicle components.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
2006-2010	921
2003-2004	921

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Wedge bulb (T15). 12V, 16W.	921

Other Locations

Additional Notes

The INFINITI M45 uses the 921 bulb size across all listed model years for the back up light position.
The 921 is an ANSI-standardized bulb type, meaning its specifications conform to a defined North American standard recognized in both the United States and Canada.
The 921 bulb follows a wedge-style base design, classified under the T15 envelope designation, which refers to a tubular glass envelope measuring 15 eighths of an inch in width.
The wedge base on the 921 eliminates the need for a separate metal base or locking pins, as the glass envelope itself acts as the retention mechanism within the socket.
The 921 operates at 12 volts and draws 16 watts, which is consistent with standard automotive low-voltage electrical systems.
The 921 bulb size applies to the INFINITI M45 across the 2003-2004 and 2006-2010 model years.
The T15 wedge form factor is shared by several bulb numbers in the same family, and substitution with visually similar wedge bulbs of differing wattage ratings may affect circuit performance or socket integrity.