Dodge Diplomat Map Light Bulb Size

Additional Notes

• The Dodge Diplomat map light bulb specifications cover model years 1977 through 1989, spanning three distinct bulb types across that range.
• The 912 bulb is the most widely used type in these specifications, fitted across the 1981-1989 model years, representing nine of the thirteen total entries.
• The 912 is a T15 wedge-base bulb operating at 12 volts and 12 watts, standardized under ANSI for the US and Canadian markets. It is classified as a variant of the 921 bulb.
• The wedge base of the 912 means the bulb is held in its socket by the tension of the glass envelope itself rather than by a separate metal base, which is a common trait in interior lighting applications.
• The 1980 Dodge Diplomat map light uses the 211-2 bulb, a festoon type with an SV8.5 base and a 41mm length, also rated at 12 volts and 12 watts.
• Festoon bulbs make contact at both ends of the tube. The 211-2 uses an SV8.5 base, while the 562 uses end-cap contacts, making the two festoon types physically non-interchangeable despite sharing the same voltage and wattage ratings.
• The 562 bulb is specified for the 1977-1979 model years. It is a festoon bulb with a 44mm length and end-cap contacts, rated at 12 volts and 12 watts.
• Although the 211-2 and 562 are both ANSI-standard festoon bulbs with identical electrical ratings, their differing lengths (41mm versus 44mm) and base types mean one cannot substitute for the other in the Dodge Diplomat map light housing.
• All three bulb types in these specifications share the same 12-volt, 12-watt electrical rating, though their physical formats differ and are not interchangeable with one another.
• The 912 bulb, as a T15 wedge type, is physically incompatible with the festoon sockets used in the 1977-1980 model years, and the festoon bulbs from those years are equally incompatible with the wedge socket used from 1981 onward.