Ford Aerostar Map Light Bulb Size

The Ford Aerostar map light utilizes bulb size 912 and bulb size 211-2 for illumination purposes. Available data covers the specific range from 1986 through 1997 for the mentioned vehicle components.

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
1987-1997	912
1986	211-2

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Wedge bulb (T15). Variant of 921. 12V, 12W.	912
ANSI standard (US & Canada). Festoon bulb, 41mm length, SV8.5 base. 12V, 12W.	211-2

Other Locations

Additional Notes

The Ford Aerostar map light uses the 912 bulb across 1987-1997, making it the dominant fitment across nearly the full production span covered by these specifications.
The 912 is an ANSI-standard wedge bulb with a T15 form factor, rated at 12 volts and 12 watts, and is classified as a variant of the 921 bulb.
The T15 designation refers to the bulb's tubular shape, with the numerical suffix indicating its width in eighths of an inch, placing it in the mid-range of wedge bulb sizing.
Wedge bulbs use a pinched glass base to make direct electrical contact with the socket, eliminating the need for a separate metal base or bayonet pins.
The 1986 Ford Aerostar map light takes a 211-2 festoon bulb rather than a wedge type, representing a distinct socket design incompatible with the 912.
The 211-2 is also ANSI-standard and shares the same 12-volt, 12-watt electrical rating as the 912, but its physical construction differs entirely, using a 41mm cylindrical body with an SV8.5 base.
Festoon bulbs make contact through metal caps at each end of the tube, which seat into spring-loaded clips within the socket, a mounting method that is not interchangeable with wedge sockets.
The SV8.5 base designation on the 211-2 indicates a single-contact festoon base with an 8.5mm cap width, a standard measurement used to match the bulb to its socket type.
Because the 912 and 211-2 use fundamentally different base types, the 1986 model year requires a separate fitment that is not a drop-in substitute for the bulb used in any other Aerostar year listed.
Both bulb types carry ANSI standardization applicable to the US and Canadian markets, meaning they conform to a defined set of electrical and physical tolerances recognized across those regions.