Chevrolet El Camino Map Light Bulb Size

Additional Notes

• The Chevrolet El Camino map light bulb specifications cover model years 1964-1977, with two distinct bulb types used across that span: the 561 and the 562.
• Both the 561 and 562 are ANSI-standardized festoon bulbs rated at 12 volts and 12 watts, sharing a 44mm length and end-cap contact design.
• A festoon bulb is a cylindrical lamp that makes electrical contact through metal caps at each end rather than through a base or pins, fitting into spring-loaded holders within the fixture.
• The Chevrolet El Camino (1974-1977) uses the 561 bulb for the map light position.
• Model years 1964-1971 use the 562 bulb instead, representing the longer-running fitment across this vehicle's history in the specifications.
• Despite sharing identical voltage, wattage, physical length, and contact type, the 561 and 562 carry separate ANSI designations, which indicates they are distinct part numbers and are not formally listed as interchangeable.
• The end-cap contact design means electrical current passes through both ends of the bulb body, a construction common in interior courtesy and map lighting applications where the fixture provides tension-based retention.
• Both bulb types operate on a 12-volt system, consistent with the standard automotive electrical architecture used in production vehicles of these model years.