Pontiac Sunbird Headlight Bulb Size

Additional Notes

• The Pontiac Sunbird used two distinct headlamp system types across its production years: sealed beam units and halogen capsule headlamps. Models from 1989-1994 accommodated either system depending on how the vehicle was originally equipped, while models from 1976-1980 used sealed beam units exclusively.
• The 9005 and 9006 bulbs are the replaceable halogen capsule types found in 1989-1994 Sunbirds equipped with halogen capsule headlamps. The 9005 handles high beam duties at 65W, while the 9006 handles low beam duties at 55W. Both operate at 12V and conform to ANSI standards applicable in the US and Canada.
• The 9005 uses a P20d base and the 9006 uses a P22d base. These two base types are physically incompatible with each other, meaning the high beam and low beam bulbs cannot be interchanged between sockets despite their otherwise similar construction.
• Sealed beam headlamp units, including the H4701, H4703, H4651, H4652, and H4656 types, are not replaceable bulbs. When a sealed beam unit fails, the entire lens-reflector-filament assembly is replaced as a single unit.
• The Pontiac Sunbird models from 1989-1994 with sealed beam headlamps used 7-inch round units: the H4701 for high beam and the H4703 for low beam. These are distinct units and are not interchangeable with each other.
• Models from 1977-1980 used the H4651 for high beam and the H4652 for low beam, both of which are 4x6-inch rectangular sealed beam units. The H4652 is a variant of the H4651, and the two serve different beam functions and are not interchangeable.
• The 1976 Sunbird used the H4656 for its low beam, which is a separate 4x6-inch rectangular sealed beam unit distinct from the H4652 used in 1977-1980 low beam positions. This makes the 1976 low beam unit non-interchangeable with those of the following model years.