Chevrolet Colorado Trunk Bulb Size

The Chevrolet Colorado trunk utilizes a 921 bulb size for illumination within the rear storage area of the vehicle. Data for the specific component covers the range from 2015 to 2020.

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
2020	921 (Uses Center High Mount Stop Light Bulb)
2017-2019	921 (Open Cargo)
2015-2016	921 (Open Trunk)

Bulb Specifications

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

Other Locations

Additional Notes

The 921 bulb is the sole bulb size listed across all six model years in these specifications, covering the Chevrolet Colorado from 2015 through 2020.
The 921 is an ANSI-standard wedge-type bulb, classified under the T15 designation, operating at 12 volts and rated at 16 watts.
The T15 wedge base design means the bulb is held in place by friction against the socket walls rather than by a bayonet or screw mechanism, which is a common trait in cargo and trunk lighting applications.
For the 2015-2016 model years, the application is labeled "Open Trunk," while the 2017-2019 model years carry the label "Open Cargo," reflecting a difference in how the lighting position is categorized across those year groups.
The 2020 Chevrolet Colorado entry differs from all other listed years in that the 921 bulb is designated for the Center High Mount Stop Light rather than a cargo or trunk position, making it a functionally distinct application despite sharing the same bulb size.
Because the 921 bulb serves both cargo area illumination and stop light functions across different model years, direct substitution between positions should account for the differing circuit and functional requirements of each application.