Buick Regal Headlight Bulb Size

Additional Notes

• The 9012 is one of the most frequently specified bulb types across the Buick Regal headlight data, appearing in both high beam and low beam positions for the 2014-2017 model years under halogen capsule headlamp configurations. It is a single-filament enhanced halogen bulb operating at 12V and 55W, built to the ANSI standard and fitted with a PX22d base.
• The D3S HID bulb shares equal prevalence with the 9012 across the 2014-2017 Buick Regal, serving both high and low beam positions in vehicles equipped with HID headlamps. Unlike conventional halogen types, the D3S is a mercury-free xenon discharge bulb operating at 42V and 35W, with an integral ignitor and a PK32d-5 base designed specifically for projector-type housings.
• The D1S HID bulb is specified for both high and low beam positions on the 2011-2013 Regal with HID headlamps. It differs from the D3S in its higher operating voltage of 85V and its PK32d-2 base, making the two types electrically and physically incompatible despite their similar wattage of 35W.
• The 9005 and 9006 bulbs are specified for high beam and low beam positions respectively across the 1988-2004 Regal. Both are ANSI-standard single-filament halogen types, though the 9005 operates at 65W with a P20d base while the 9006 operates at 55W with a P22d base. The differing wattages and base types mean the two are not interchangeable.
• Sealed beam units account for all headlight specifications from 1973 through 1987. The H6024 is a 7-inch round unit used on the 1973-1975 Regal, the H6054 is a 5x7-inch rectangular unit used on the 1978-1980 Regal, and the H4651, H4652, and H4656 are all 4x6-inch rectangular units used across various years from 1976 through 1987. In all these cases, the entire sealed beam assembly is replaced rather than an individual bulb.
• The low beam specifications for the 2011-2013 Regal with halogen capsule headlamps call for the H11, an ECE-standard single-filament halogen bulb with a PGJ19-2 base rated at 12V and 55W. The corresponding high beam position for those same years uses the H7, which shares the same voltage and wattage but carries a PX26d base, making the two types non-interchangeable despite their identical electrical ratings.
• The 2014 Regal high beam position lists three distinct bulb sizes: H7, 9012 with halogen capsule headlamps, and D3S with HID headlamps. This indicates that three separate headlamp system variants were available for that model year, each requiring a different and incompatible bulb type.
• The 7443 dual-filament wedge bulb appears only in the 2017 Regal low beam data under a halogen designation, rated at 12V with a split wattage of 21W and 5W across its two filaments. Its T20 wedge base and dual-filament construction distinguish it from all other bulb types listed in the specifications.