Cadillac CTS Trunk Bulb Size

The Cadillac CTS trunk utilizes a 211-2 bulb size for illumination within the rear storage compartment of the vehicle. Data for the specified component covers the range from 2003 through 2019.

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
2016-2019	211-2
2003-2013	211-2

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 41mm length, SV8.5 base. 12V, 12W.	211-2

Other Locations

Additional Notes

The Cadillac CTS uses the 211-2 bulb for the trunk across all listed model years from 2003 to 2019, with the exception of 2014 and 2015, which are not present in the specifications.
The 211-2 is a festoon-style bulb, meaning it mounts by pressing lengthwise between two spring clips rather than inserting into a socket with a traditional base pin.
The 211-2 carries an SV8.5 base designation, which refers to the 8.5mm cap fittings at each end of the festoon body that contact the spring clip holders.
At 41mm in length, the 211-2 must seat correctly within the spring clip span of the trunk lamp housing; a festoon bulb of a different length would not make proper contact.
The 211-2 operates at 12 volts and 12 watts, which are standard values for low-draw interior lighting in automotive applications.
The 211-2 is an ANSI-standardized bulb recognized in both the United States and Canada, meaning the designation refers to a consistent specification rather than a proprietary part number.
Because the 211-2 designation is an ANSI standard, bulbs carrying that number from different manufacturers are expected to share the same voltage, wattage, base type, and body length.
The festoon form factor of the 211-2 is common in trunk, map, and dome lighting positions across many vehicle makes, which contributes to its wide availability as a replacement part.