The Hino SG231 front and rear turn signal bulbs both utilize a 1156 bulb size for replacement applications. The replacement chart covers vehicle production spanning 1989 to 1992.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 1156 bulb is the sole turn signal bulb type specified for the Hino SG231 across all listed model years and positions.
Both the front and rear turn signal positions on the SG231 use the 1156 bulb for the 1989-1992 model years.
The 1156 is a single-filament bulb, meaning it serves one lighting function only, as opposed to dual-filament bulbs that handle two functions such as braking and signaling from a single unit.
The 1156 operates at 12 volts and 21 watts, which places it within the standard range for automotive turn signal applications.
The 1156 uses a BA15s bayonet base, a single-contact mount where the "s" denotes a single pin, distinguishing it from the BA15d, which carries two pins for dual-filament use.
The 1156 is an ANSI-standardized bulb recognized in both the United States and Canada, meaning its physical and electrical specifications conform to a defined industry standard rather than a proprietary format.
Because the BA15s base is a single-contact design, substituting a dual-contact BA15d bulb would result in an incompatible fit despite the similar bayonet housing style.