The Audi Q7 fog light requires a specific H7 bulb size for proper installation and operation within the front lighting assembly. Data for the specified component covers the range from 2007 through 2009.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Audi Q7 front fog light uses two distinct bulb types across its model years, with H7 specified for 2007-2009 and H11 specified for 2010-2015.
Both the H11 and H7 are single-filament halogen bulbs operating at 12V and 55W, placing them in the same power class despite their different base configurations.
The H11 uses a PGJ19-2 base, while the H7 uses a PX26d base. These bases are physically incompatible, meaning the two bulb types are not interchangeable with each other.
Both the H11 and H7 are ECE-rated standards, originally developed for European and worldwide markets, though both also carry approval for use in the United States.
The 921 is a wedge-style bulb of the T15 form factor, rated at 12V and 16W. Its significantly lower wattage reflects its role as a rear fog light rather than a forward-projecting lamp.
The 921 bulb follows the ANSI standard, which is the North American counterpart to the ECE system used by the H-series bulbs. This places the rear fog light in a different regulatory and physical category than the front fog light.
The Audi Q7 rear fog light uses the 921 bulb for the 2013-2015 and 2018-2019 model years.
The front fog light specifications span 2007-2015, covering a longer range of model years than the rear fog light specifications, which cover 2013-2015 and 2018-2019.