Fiat X-1/9 License Plate Bulb Size

The Fiat X-1/9 license plate light requires bulb sizes 67 and 89 for proper illumination. Provided data covers the specific range from 1974 through 1983 for the vehicle.

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
1981-1983	67
1980	89
1979	67
1974-1978	89

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Lower wattage variant of 1156. 12V, 8W.	67
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Lower wattage variant of 1156. 12V, 13W.	89

Other Locations

Additional Notes

The Fiat X-1/9 license plate bulb specifications cover model years 1974 through 1983, with two distinct bulb sizes used across that span.
The bulb 89 is the more frequently specified of the two, appearing in the Fiat X-1/9 for 1974-1978 and again in 1980.
The bulb 67 is specified for 1979 and 1981-1983.
Both the 67 and 89 are ANSI-standard bulbs recognized in the US and Canadian markets, and both use a BA15s single-contact bayonet base.
The BA15s base is a single-contact design, meaning the two bulbs are physically interchangeable at the socket level despite differing in wattage.
The bulb 67 operates at 12V and 8W, while the bulb 89 operates at 12V and 13W, representing a notable difference in power draw between the two fitments.
Both bulbs are single-filament types, which is consistent with their application in a non-switching, always-on license plate light function.
Each bulb is described as a lower wattage variant of the 1156, a widely available automotive bulb, indicating shared base geometry with that more common reference type.
Because the 67 and 89 share the same BA15s base, physical installation of either into the other's socket is possible, though the wattage difference means the specified bulb should be used to match the original electrical load for each model year.