Pontiac Ventura Dome Light Bulb Size

The Pontiac Ventura dome light requires bulb size 561, 211-2, or 1004 depending on the specific version of the vehicle. Available information covers a span from 1960 through 1977.

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
1977	561
1971-1976	211-2
1961	211-2
1960	1004

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 44mm length, end-cap contacts. 12V, 12W.	561
ANSI standard (US & Canada). Festoon bulb, 41mm length, SV8.5 base. 12V, 12W.	211-2
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Variant of 1157. 12V, 21/5W.	1004

Other Locations

Additional Notes

The 211-2 is the most frequently specified dome light bulb across the Pontiac Ventura's model history, covering the 1961 and 1971-1976 model years.
The 211-2 is a festoon-type bulb rated at 12V and 12W, with a 41mm length and an SV8.5 base, conforming to ANSI standards recognized in both the US and Canada.
Festoon bulbs make contact at both ends of the tube rather than through a traditional socket base, which is a defining characteristic of the festoon form factor shared by both the 211-2 and the 561.
The 1977 Pontiac Ventura uses the 561 bulb rather than the 211-2 found in prior model years, making it the only year in the specifications to require the 561.
The 561 is also a festoon bulb rated at 12V and 12W, but its 44mm length differs from the 41mm of the 211-2, meaning the two are not interchangeable despite sharing the same wattage and voltage rating.
The 1960 Pontiac Ventura uses the 1004, a dual-filament bulb with a BAY15d bayonet base rated at 12V and 21/5W, which is a fundamentally different construction from the festoon bulbs specified for all other model years.
The 1004 is noted as a variant of the 1157, a widely recognized automotive bulb, though the 1004 carries a different wattage rating than the standard 1157.
The BAY15d bayonet base of the 1004 uses an offset double-pin design, a feature that prevents incorrect insertion by ensuring the bulb can only be seated in one orientation.
All three bulb types listed in the specifications, the 211-2, the 561, and the 1004, conform to ANSI standards applicable in both the US and Canada.
The shift from the 1004 in 1960 to the 211-2 in 1961 represents a change in both bulb construction and base type for the Ventura's dome light application.