GMC Envoy Dome Light Bulb Size

The GMC Envoy dome light requires bulb sizes 212-2 and 194 for the interior lighting system. Available data for the specified components covers the period from 2002 through 2009.

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
2007-2009	212-2
2002-2006	194

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 41mm length, SV8.5 base. 12V, 12W.	212-2
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 3.78W.	194

Other Locations

Additional Notes

The GMC Envoy dome light uses two distinct bulb types across its model years, with the 212-2 specified for 2007-2009 and the 194 specified for 2002-2006.
The 212-2 is a festoon-style bulb, meaning it is cylindrical and held in place by spring clips at each end rather than inserted into a socket.
The 212-2 operates at 12 volts and 12 watts, drawing notably more power than the 194 used in earlier model years.
The 212-2 measures 41mm in length and uses an SV8.5 base, which is the standard festoon base designation for that size class.
The 194 is a T10 miniature wedge bulb, a form factor that uses a wedge-shaped plastic base inserted directly into a friction-fit socket with no separate metal base pins.
The 194 operates at 12 volts and 3.78 watts, placing it in the low-wattage range typical of interior courtesy and indicator lighting.
Both the 212-2 and 194 conform to ANSI standards applicable in the United States and Canada.
The 212-2 and 194 are not interchangeable, as they differ in physical form factor, base type, wattage, and mounting method.
Installing a 212-2 festoon bulb in a socket designed for a 194 wedge base, or vice versa, would be physically incompatible without modification to the fixture.
The wattage difference between the two bulb types means that substituting one for the other could also affect circuit load, even if an adapter were used.