Ford Sunliner Dome Light Bulb Size

The Ford Sunliner dome light requires bulb size 1003 or 63 depending on the specific application. Data for the bulb sizes covers the range from 1952 to 1960.

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
1956-1960	1003
1952-1955	63

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.	1003
ANSI standard (US & Canada). Single-filament bulb with BA9s base. 12V, 0.63W.	63

Other Locations

Additional Notes

The Ford Sunliner dome light specifications cover model years 1952 through 1960, with two distinct bulb types used across that span.
The 1003 bulb is a single-filament type rated at 12V and 21W, fitted with a BA15s bayonet base, and classified under the ANSI standard for the US and Canadian markets.
The BA15s bayonet base uses a single contact pin, which means it is not interchangeable with dual-pin bayonet variants such as the BA15d.
The Ford Sunliner (1956-1960) uses the 1003 bulb for the dome light.
The 63 bulb is also a single-filament type rated at 12V, but draws only 0.63W, making it significantly lower in output than the 1003. It uses a BA9s base.
The BA9s base is a miniature bayonet fitting, physically smaller than the BA15s, and the two base types are not interchangeable.
The Ford Sunliner (1952-1955) uses the 63 bulb for the dome light.
Both the 1003 and 63 bulbs operate on a 12V electrical system, consistent with the 12-volt standard that became widespread in American passenger vehicles during the 1950s.
The shift from the 63 to the 1003 between the 1955 and 1956 model years represents a change in both base type and wattage, meaning the two bulbs are not substitutes for one another.
Both bulb types conform to ANSI standards applicable to the US and Canadian markets.