The Mazda RX-3 headlight bulb sizes consist of H5001 for high beam and H5006 for low beam applications, with each bulb size engineered for specific lighting functions. The replacement chart covers vehicle production spanning 1972 to 1978, detailing bulb specifications across the model's manufacturing period.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Mazda RX-3 uses the H5001 sealed beam unit for high beam headlights across all model years from 1972-1978. This unit conforms to the ANSI standard recognized in the United States and Canada and operates on a 12V electrical system.
The H5001 is a 4-inch square sealed beam unit. Unlike bulb-based lighting systems, the entire sealed beam assembly is the replaceable component rather than an internal filament or capsule.
Low beam headlights on the RX-3 use the H5006 sealed beam unit across the same 1972-1978 model year range. It also conforms to the ANSI standard for the US and Canadian markets and runs on 12V.
The H5006 is a 5.75-inch round sealed beam unit. As with the H5001, the full assembly is replaced as a single unit rather than any individual internal component.
The H5001 and H5006 are not interchangeable with each other. The high beam and low beam positions use physically distinct sealed beam formats, one square and one round, which prevents cross-fitment between the two positions.
Because both the H5001 and H5006 are sealed beam units rather than bulb-and-housing systems, aftermarket or replacement units must match the original ANSI-designated form factor to fit the RX-3 headlight housing correctly.