The Mercedes-Benz E300 front fog light uses H1 and H3 bulb sizes, while the rear fog light requires a P21W size bulb. The replacement chart covers vehicle production years spanning 1995 to 1999 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 E300 front fog light uses the H1 bulb for the 1996-1999 model years, while the 1995 model year uses the H3 bulb instead.
The H1 and H3 are not interchangeable despite sharing identical voltage and wattage ratings of 12V and 55W, as each uses a different base type.
The H1 bulb uses a P14.5s base, while the H3 bulb uses a PK22s base, making the two physically incompatible with each other's housings.
Both the H1 and H3 are single-filament halogen bulbs built to ECE standards, with approval for use in Europe, worldwide markets, the United States, and Japan.
The rear fog light on the Mercedes-Benz E300 uses the P21W bulb across all listed model years, from 1995-1999.
The P21W is a single-filament signalling bulb rated at 12V and 21W, operating at a significantly lower wattage than the halogen fog light bulbs used at the front.
The P21W uses a BA15s bayonet base, which is a single-contact bayonet fitting and is not compatible with the pin-type bases found on the H1 or H3 bulbs.
All three bulb types listed in these specifications conform to ECE standards, indicating suitability for road use in markets that recognize that regulatory framework.