Cadillac Escalade EXT Map Light Bulb Size

The Cadillac Escalade EXT map light utilizes bulb sizes 212-2 and 578 for the interior lighting system. Provided information covers the specific time range from 2002 through 2013.

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
2007-2013	212-2
2002-2006	578

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 41mm length, SV8.5 base. 12V, 12W.	212-2
ANSI standard (US & Canada). Festoon bulb, 41mm length, end-cap contacts. 12V, 12W.	578

Other Locations

Additional Notes

The Cadillac Escalade EXT map light uses two distinct bulb types across its production run, with the 578 fitted to 2002-2006 models and the 212-2 fitted to 2007-2013 models.
Both the 212-2 and 578 are festoon-style bulbs, meaning they are cylindrical in form and mount by bridging two contact points at opposite ends of a housing rather than inserting into a socket.
Both bulbs share identical electrical ratings of 12 volts and 12 watts, as well as an identical 41mm length, making their physical and power profiles equivalent.
Despite those shared specifications, the 212-2 uses an SV8.5 base, which features a central pin contact at each end, while the 578 uses flat end-cap contacts, meaning the two types are not interchangeable without a compatible housing.
Both bulb types carry ANSI standard designations recognized in the United States and Canada, indicating conformance to a defined set of performance and dimensional criteria.
The 12-watt rating places both bulbs in the low-wattage incandescent category typical of interior courtesy and map lighting applications in passenger vehicles.
The SV8.5 designation on the 212-2 refers to a specific festoon base standard where the 8.5 indicates the nominal contact width in millimeters, a detail relevant when sourcing a direct replacement.