Cadillac Series 62 Dome Light Bulb Size

The Cadillac Series 62 dome light utilizes bulb sizes 90 and 1004 depending on the specific production period. Available information covers the span from 1953 through 1964.

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
1963-1964	1004
1959-1962	90
1953-1958	1004

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Variant of 1157. 12V, 21/5W.	1004
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 13W.	90

Other Locations

Additional Notes

The Cadillac Series 62 dome light draws from two bulb types across its 1953-1964 model range: the 1004 and the 90, both of which are ANSI-standardized bulbs used in the United States and Canada.
The 1004 bulb is a dual-filament unit rated at 12V and 21/5W, mounted on a BAY15d bayonet base. The dual-filament design means it carries two separate filaments within a single envelope, each operating at a different wattage.
The 90 bulb is a single-filament unit rated at 12V and 13W, mounted on a BA15s bayonet base. The BA15s base differs from the BAY15d in that it has a single contact pin rather than two offset pins.
The BAY15d base of the 1004 and the BA15s base of the 90 are physically distinct and not interchangeable, meaning a 90 cannot be substituted into a socket designed for a 1004, and vice versa.
The 1004 is described as a variant of the 1157, a widely recognized automotive bulb. While the two share a BAY15d base, they are not identical, and substituting one for the other without confirming voltage and wattage compatibility is not advised.
The Cadillac Series 62 used the 1004 bulb for its dome light across the 1953-1958 model years, then transitioned to the 90 bulb for the 1959-1962 model years.
The Series 62 returned to the 1004 bulb for the 1963-1964 model years, meaning the 90 bulb was specific to the four-year span between those two periods of 1004 usage.
Because the 1004 and 90 bulbs share the same 12V operating voltage, the distinction between them for dome light fitment lies primarily in their base type, filament count, and wattage output rather than voltage compatibility.