Ford Custom Dome Light Bulb Size

The Ford Custom dome light utilizes unique bulb sizes 561, 105, 1003, and 63 depending on the specific version of the vehicle. Data for the lighting components covers the range from 1950 to 1972.

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
1972	561
1970-1971	105
1964-1969	1003
1957	1003
1950-1952	63

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 44mm length, end-cap contacts. 12V, 12W.	561
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Variant of 1156. 12V, 13W.	105
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 Custom dome light specifications span model years 1950 through 1972, with four distinct bulb types used across that period: the 561, 105, 1003, and 63.
The 1003 is the most frequently specified bulb in these records, covering the Ford Custom across 1957 and 1964-1969. It is a single-filament bulb with a BA15s bayonet base, rated at 12V and 21W.
The BA15s bayonet base is shared between the 1003 and the 105, meaning both bulbs use the same base type. However, their wattage ratings differ, with the 1003 drawing 21W and the 105 drawing 13W, which makes them non-interchangeable despite the shared base.
The 105 bulb is described as a variant of the 1156 and is specified for the Ford Custom in 1970-1971. Its single-filament, BA15s bayonet construction places it in the same base family as the 1003, though it operates at a lower wattage.
The 1972 Ford Custom uses the 561, a festoon-type bulb with a 44mm length and end-cap contacts. This physical format is fundamentally different from the bayonet-base bulbs used in prior model years, indicating a change in the dome light socket design.
The 63 bulb is specified for the Ford Custom in 1950-1952. It uses a BA9s base, which is a smaller bayonet fitting than the BA15s found on the 1003 and 105, and it operates at a notably low 0.63W, consistent with indicator or courtesy light applications of that era.
All four bulb types in these specifications conform to ANSI standards applicable in both the United States and Canada.