The Mitsubishi Sigma front and rear turn signal bulbs both utilize a 1156 size bulb for proper operation. The replacement chart covers 1989 to 1990 model 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 1156 is the sole bulb type listed across all turn signal positions for the Mitsubishi Sigma, covering both the 1989-1990 model years.
The 1156 is a single-filament bulb, meaning it serves one lighting function per socket rather than combining two functions such as braking and running light in a single unit.
It operates on a BA15s bayonet base, a single-contact fitting where the "s" denotes a single contact pin offset to one side, which prevents incorrect insertion orientation.
The 1156 carries a 12V, 21W electrical rating, placing it in the standard range for automotive turn signal applications on 12-volt vehicle electrical systems.
The ANSI designation confirms the 1156 conforms to a standardized specification recognized across the United States and Canada, establishing consistent physical and electrical characteristics across manufacturers.
The front and rear turn signal positions on the Sigma share the same 1156 bulb type for both listed model years, indicating socket compatibility between those positions.
Because the 1156 is a single-contact bayonet type, it is not directly interchangeable with the 1157, which uses a dual-contact BA15d base and carries two filaments, despite the physical similarity of the bayonet housing.