Land Rover Discovery high and low beam headlight bulbs utilize H7 and 9003 size specifications across multiple generations. The replacement chart documents bulb specifications spanning 1994 to 2019 production years.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The H7 is a single-filament halogen bulb operating at 12V and 55W, built to the ECE standard used in Europe and worldwide, with a PX26d base. It carries approval in the US and Japan as well.
The 9003 is a dual-filament halogen bulb operating at 12V with a 60W high beam filament and a 55W low beam filament, built to the ANSI standard used in the US and Canada, with a P43t base.
Because the 9003 carries both filaments in a single housing, it serves both high and low beam functions from one bulb, whereas the H7 handles only one beam function per bulb due to its single-filament design.
The Land Rover Discovery used the 9003 bulb for both high and low beam headlights across the 1994-2002 model years.
The H7 bulb replaced the 9003 starting with the 2003-2004 model years, representing a shift from the ANSI-standard dual-filament design to the ECE-standard single-filament design.
For the 2017-2019 Land Rover Discovery, the H7 specification applies specifically to vehicles equipped with Halogen Capsule Headlamps, indicating that other headlamp configurations on those model years follow different bulb requirements not covered by this specification.
The PX26d base of the H7 and the P43t base of the 9003 are physically incompatible, meaning the two bulb types are not interchangeable despite both being 12V halogen bulbs used in the same vehicle line across different years.