Audi A6 Back Up Light Bulb Size

The Audi A6 back up light bulb uses 2 distinct sizes: 921 and 7506, with each bulb size corresponding to specific vehicle production specifications. The replacement chart covers data spanning from 1995 to 2015, detailing which bulb size applies across the model's production years.

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
2005-2015	921
1995-2004	7506

Bulb Specifications

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

Other Locations

Additional Notes

The Audi A6 back up light specifications cover model years 1995 through 2015, split between two distinct bulb sizes across that span.
The 921 bulb is specified for the Audi A6 from 2005 through 2015, making it the bulb type associated with the majority of model years in these specifications.
The 921 is an ANSI-standardized bulb, meaning it conforms to a defined North American specification used across the United States and Canada.
The 921 uses a wedge-style base, classified as T15, which refers to a tubular bulb body approximately 15 eighths of an inch wide that is held in its socket by friction rather than by pins or a bayonet mechanism.
The 921 operates at 12 volts and draws 16 watts, which is consistent with standard automotive electrical systems.
The 7506 bulb is specified for the Audi A6 from 1995 through 2004, representing the earlier generation of fitment in these specifications.
The 921 and 7506 are not the same bulb type, and the two designations are not interchangeable despite both serving the back up light function across different model years of the same vehicle.
The transition from the 7506 to the 921 specification occurs between the 2004 and 2005 model years of the Audi A6.