The Hino SF17 front and rear turn signal bulbs utilize either 1156 or 1157 bulb sizes depending on the specific application. The replacement chart covers vehicle production spanning 1988 to 1991 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 SF17 uses two distinct bulb types across its turn signal positions: the 1156 for model years 1989-1991 and the 1157 for the 1988 model year, applying equally to both front and rear turn signal positions.
The 1156 is a single-filament bulb operating at 12V and 21W, fitted with a BA15s bayonet base. The single filament means it serves one lighting function only, which in this context is the turn signal.
The 1157 is a dual-filament bulb operating at 12V with a 21W/5W filament rating, fitted with a BAY15d bayonet base. The two filaments allow it to serve two separate lighting functions at different wattages within a single housing.
The BA15s base of the 1156 and the BAY15d base of the 1157 are not interchangeable. The BAY15d base has offset locating pins to prevent incorrect installation, while the BA15s base has symmetrical pins.
Despite sharing a 12V operating voltage and a 21W turn signal filament rating, the 1156 and 1157 are not drop-in substitutes for one another due to their differing base configurations and filament counts.
Both the 1156 and 1157 conform to ANSI standards applicable in the United States and Canada, indicating standardized electrical and physical specifications within those markets.
The 1988 Hino SF17 is the only model year in the specification that uses the dual-filament 1157 bulb across both its front and rear turn signal positions.