Hino SG23 front side marker bulbs use 194 or 1156 size, while rear side marker bulbs use 67 size. The replacement chart covers 1987 to 1992 production years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Hino SG23 front side marker uses two different bulb types depending on the model year, with the 194 specified for 1989-1992 and the 1156 specified for 1987-1988.
The 194 is a T10 miniature wedge bulb rated at 12V and 3.78W, conforming to ANSI standards applicable in the US and Canada.
The T10 wedge base on the 194 bulb is a push-in fitment with no locking mechanism, relying on tension from the socket to hold the bulb in place.
The 1156 is a single-filament bulb with a BA15s bayonet base, rated at 12V and 21W, also conforming to ANSI standards for the US and Canadian markets.
The BA15s designation on the 1156 refers to a single-contact bayonet base with a 15mm collar, a fitment type that is not interchangeable with the wedge-style socket used by the 194.
The front side marker socket type on the Hino SG23 changed between the 1988 and 1989 model years, as the shift from the 1156 to the 194 involves incompatible base types.
The rear side marker on the Hino SG23 uses the 67 bulb for 1989-1992, which shares the BA15s bayonet base with the 1156 but operates at a significantly lower wattage of 8W versus 21W.
Because the 67 and 1156 share the same BA15s bayonet base, they are physically interchangeable in terms of fitment, though their wattage ratings differ substantially and substitution would affect circuit load.
The 194 at 3.78W and the 67 at 8W represent the lower end of the wattage range across these specifications, while the 1156 at 21W draws considerably more current than either.
All three bulb types, the 194, 1156, and 67, are rated at 12V, consistent with standard automotive electrical systems.