American Motors Ambassador Map Light Bulb Size

The American Motors Ambassador map light uses bulb sizes 1004, 1445, 194, and 561 depending on the specific application for the interior lighting component. Data for the bulb sizes covers the range from 1962 through 1974 for the specified vehicle.

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
1974	561
1971	194
1968-1970	1445
1962-1967	1004

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 44mm length, end-cap contacts. 12V, 12W.	561
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 3.78W.	194
ANSI standard (US & Canada). Single-filament bulb with BA9s base. 12V, 2W.	1445
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Variant of 1157. 12V, 21/5W.	1004

Other Locations

Additional Notes

The American Motors Ambassador map light specifications span model years 1962 through 1974, covering four distinct bulb types across that range.
The 1004 bulb is the most frequently specified type, serving the Ambassador map light across six consecutive model years from 1962-1967. It is a dual-filament bulb with a BAY15d bayonet base, rated at 12V with a 21/5W output, and is noted as a variant of the widely known 1157 bulb.
The BAY15d bayonet base on the 1004 bulb features offset pins, which is the mechanical feature that distinguishes it from single-filament bayonet types and prevents incorrect installation of incompatible bulbs.
The 1445 bulb is specified for the American Motors Ambassador map light across model years 1968-1970. It is a single-filament bulb with a BA9s base, rated at 12V and 2W, making it a notably low-wattage lamp relative to the other types in these specifications.
The BA9s base on the 1445 bulb is a miniature bayonet cap with a 9mm cap width, a physically small fitting that is not interchangeable with the larger BAY15d base used by the 1004 bulb.
The 1971 American Motors Ambassador map light uses the 194 bulb, a T10 miniature wedge type rated at 12V and 3.78W. Its wedge base relies on the tension of the socket contacts rather than a bayonet or cap fitting to maintain connection.
The 1974 American Motors Ambassador map light uses the 561 bulb, a festoon type with a 44mm length and end-cap contacts. At 12V and 12W, it carries the highest wattage rating of any bulb type listed in these specifications.
Festoon bulbs such as the 561 are held in place by spring-loaded clips at each end rather than a rotational or push-fit base, a mounting method that is mechanically incompatible with the socket types used by the other bulbs in these specifications.
All four bulb types listed across these specifications conform to ANSI standards applicable in both the United States and Canada, indicating a standardized electrical and dimensional classification system governs each type.
Because the map light bulb type changes across multiple model years, the 1004, 1445, 194, and 561 bulbs are not interchangeable with one another despite all operating on a 12V system, as each uses a distinct base type or mounting method.