Acura RDX front side marker bulb uses 168 size while rear side marker bulb uses 7443 or 168 size. Replacement chart covers 2007 through 2018 model years with bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Acura RDX front side marker position uses the 168 bulb across all listed model years from 2007-2018, with no variation in bulb type across that span.
The 168 bulb is an ANSI-standard miniature wedge type with a T10 form factor, rated at 12V and 4.9W, placing it in the low-wattage category typical of parking and marker lighting applications.
The rear side marker position on the Acura RDX uses two distinct bulb types depending on the model year, making year verification essential before replacement.
For the 2007-2012 rear side marker, the RDX uses the same 168 bulb specified for the front position, meaning both positions share an identical bulb in those years.
The 7443 bulb replaces the 168 in the rear side marker position for the 2013-2015 model years, representing a significant change in bulb specification for that location.
The 7443 is an ANSI-standard dual-filament wedge bulb with a T20 form factor, rated at 12V with a 21W/5W output, making it physically and electrically incompatible with sockets designed for the single-filament 168.
The T20 form factor of the 7443 is larger than the T10 form factor of the 168, meaning the two bulbs are not interchangeable despite both being wedge-base types.
The wattage difference between the 168 (4.9W) and the 7443 (21W/5W) is substantial, and substituting one for the other in a socket not designed for it risks electrical or fitment issues.
The dual-filament nature of the 7443 indicates it serves a combined function in the 2013-2015 rear side marker circuit, whereas the single-filament 168 serves a simpler, dedicated marker role in earlier years.
Both the 168 and 7443 conform to ANSI standards applicable in the United States and Canada, indicating compliance with North American automotive lighting regulations.