Mitsubishi Sigma high beam headlight bulbs use 9005 size while low beam headlight bulbs use 9006 size. The replacement chart covers 1989 to 1990 vehicle 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 Mitsubishi Sigma uses the 9005 bulb for high beam and the 9006 bulb for low beam across the 1989-1990 model years.
Both the 9005 and 9006 are single-filament halogen bulbs, meaning each handles only one lighting function rather than combining high and low beam output in a single unit.
The 9005 operates at 12V and 65W, while the 9006 operates at 12V and 55W. The higher wattage of the 9005 reflects the greater light output typically associated with high beam applications.
The 9005 uses a P20d base and the 9006 uses a P22d base. These two base types are physically distinct, which prevents the bulbs from being interchanged between the high and low beam sockets.
Both bulbs conform to ANSI standards applicable in the United States and Canada, a classification that governs their electrical and physical specifications within those markets.