BMW 325 high beam headlight bulbs measure 9005 or H5001 in size, while low beam headlight bulbs measure 9006 or H5006 in size. The replacement chart covers 1986 to 1988 model 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 BMW 325 transitioned from sealed beam headlight units to replaceable halogen bulbs between the 1987 and 1988 model years, representing a change in both high beam and low beam fitment.
The 1986-1987 BMW 325 high beam position uses the H5001, a 4-inch square sealed beam unit operating at 12V. The entire unit is replaced rather than an internal bulb, as the light source is integral to the assembly.
The 1986-1987 low beam position uses the H5006, a 5.75-inch round sealed beam unit also operating at 12V. Like the H5001, it is a self-contained assembly with no serviceable bulb inside.
The H5001 and H5006 differ in shape and size, meaning the two sealed beam types used on the 1986-1987 325 are not interchangeable with each other despite sharing the same voltage and sealed beam construction.
For the 1988 model year, the high beam position uses the 9005, a single-filament halogen bulb with a P20d base rated at 12V and 65W, conforming to the ANSI standard applicable in the US and Canada.
The 1988 low beam position uses the 9006, a single-filament halogen bulb with a P22d base rated at 12V and 55W. The P22d base of the 9006 differs physically from the P20d base of the 9005, making the two bulbs non-interchangeable despite their similar appearance and shared voltage.
The wattage difference between the 9005 (65W) and 9006 (55W) reflects their respective roles, with the higher-output 9005 designated for high beam use and the lower-output 9006 for low beam use in the 1988 325.
All four bulb types listed across these specifications conform to ANSI standards for the US and Canadian markets.