Lincoln MKS Dome Light Bulb Size

The Lincoln MKS dome light utilizes 12961 and 578 bulb sizes for interior illumination across various production versions. Data for the specific lighting components covers the period from 2009 to 2016.

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
2013-2016	12961
2009-2012	578

Bulb Specifications

Description	Bulb Size
Philips part number. Miniature wedge bulb (T10) with W2.1x9.5d base. 12V, 5W.	12961
ANSI standard (US & Canada). Festoon bulb, 41mm length, end-cap contacts. 12V, 12W.	578

Other Locations

Additional Notes

The Lincoln MKS dome light bulb specifications cover the 2009-2016 model years, with two distinct bulb types used across that span.
Model years 2013-2016 use the 12961 bulb, a miniature wedge type with a T10 form factor and a W2.1x9.5d base, rated at 12V and 5W.
The 12961 is a Philips part number designation, meaning it originates from a manufacturer-specific catalog rather than a universal industry standard.
Model years 2009-2012 use the 578 bulb, a festoon type with end-cap contacts and a 41mm length, rated at 12V and 12W.
The 578 designation follows the ANSI standard used in the United States and Canada, making it a widely recognized reference across multiple bulb suppliers.
The wedge base of the 12961 and the end-cap festoon contacts of the 578 are physically incompatible socket types, so the two bulbs are not interchangeable with each other.
The 578 festoon bulb draws 12W, while the 12961 wedge bulb draws only 5W, reflecting a significant difference in power consumption between the two fitment generations.
A festoon bulb is held in place by spring tension against its end caps, whereas a wedge bulb is secured by friction between its base and the socket walls, representing fundamentally different retention mechanisms.