The Mercedes-Benz ML500 front fog light uses H7 and H8 bulb sizes, while the rear fog light requires P21W and P21/4W bulb sizes. The replacement chart covers 2002 through 2007 production 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 Mercedes-Benz ML500 front fog light uses two different bulb types across its model years, with H8 fitted from 2002-2005 and H7 fitted in 2006-2007.
The H7 is a single-filament halogen bulb operating at 12V and 55W, mounted on a PX26d base and produced to ECE standards with approval also granted in the US and Japan.
The H8 is a single-filament halogen bulb operating at 12V and 35W, mounted on a PGJ19-1 base and produced to ECE standards with approval also granted in the US.
Although both H7 and H8 are single-filament halogen bulbs sharing the same 12V operating voltage, their wattage and base types differ, making them non-interchangeable in the ML500 front fog light housing.
The rear fog light of the ML500 also follows a split across model years, with P21/4W fitted from 2002-2005 and P21W fitted in 2006-2007.
The P21W is a single-filament signalling bulb operating at 12V and 21W, mounted on a BA15s bayonet base and produced to ECE standards.
The P21/4W is a dual-filament signalling bulb operating at 12V with filaments rated at 21W and 4W respectively, mounted on a BAZ15d bayonet base and produced to ECE standards.
The BA15s and BAZ15d bayonet bases used by the P21W and P21/4W respectively are physically distinct, which prevents cross-fitment between the two rear fog light bulb types across the ML500 model year range.