The Hino SG23 front and rear turn signal bulbs utilize either 1156 or 1157 size bulbs depending on configuration. The replacement chart covers vehicle production spanning 1987 to 1992 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 uses two distinct bulb types across its front and rear turn signal positions: the 1156 and the 1157, both governed by ANSI standards applicable in the United States and Canada.
The 1156 bulb is a single-filament type rated at 12V and 21W, fitted with a BA15s bayonet base. Its single filament means it serves one lighting function only.
The 1157 bulb is a dual-filament type rated at 12V with two wattage outputs of 21W and 5W, fitted with a BAY15d bayonet base. The second filament allows it to serve two lighting functions simultaneously, such as turn signaling and running light duties.
The BA15s base of the 1156 and the BAY15d base of the 1157 are not interchangeable. The BAY15d base carries offset locating pins to prevent incorrect installation, while the BA15s base does not.
For the Hino SG23, the front turn signal position used the 1157 bulb in 1987-1988 and transitioned to the 1156 bulb for 1989-1992.
The rear turn signal position on the Hino SG23 follows the same pattern, with the 1157 specified for 1987-1988 and the 1156 specified for 1989-1992.
Because the 1156 and 1157 differ in both filament count and base configuration, a 1157 bulb cannot serve as a direct replacement in a socket designed for the 1156, and vice versa.
The front and rear turn signal positions share identical bulb specifications across all listed years, meaning the same bulb type applies to both positions for any given model year.