Plymouth Duster Map Light Bulb Size

The Plymouth Duster Map Light requires a bulb size of 89 for the interior lighting system. Data for the specified component covers the range from 1970 through 1976.

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
1970-1976	89

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Lower wattage variant of 1156. 12V, 13W.	89

Other Locations

Additional Notes

The Plymouth Duster uses the ANSI 89 bulb for the map light across all model years from 1970 to 1976.
The 89 bulb is a single-filament type, meaning it serves one lighting function rather than switching between two brightness levels.
It operates on a 12-volt electrical system at 13 watts, which is consistent with standard automotive low-voltage architecture.
The 89 bulb uses a BA15s bayonet base, a single-contact mount where the bulb is inserted and twisted to lock into the socket.
The 89 is recognized as a lower-wattage variant of the 1156 bulb, sharing the same BA15s base but drawing less power.
Because the 89 and 1156 share the same base type, physical fitment into the socket is possible with either bulb, though the wattage difference is a relevant electrical consideration.
The 89 bulb conforms to ANSI standards recognized in both the United States and Canada.