Mercedes-Benz A220 Turn Signal Bulb Size

Mercedes-Benz A220 rear turn signal bulb replacement uses a PY21W size. The chart covers 2019 to 2020 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.

Rear Turn Signal

Years	Bulb Size
2020	PY21W (Halogen)
2019	PY21W

Bulb Specifications

Description	Bulb Size
ECE standard (Europe & worldwide). Single-filament amber bulb with BAU15s bayonet base. 12V, 21W.	PY21W

Other Locations

Additional Notes

The PY21W is the specified rear turn signal bulb for the Mercedes-Benz A220 across the 2019-2020 model years.
The PY21W operates on a 12-volt electrical system and draws 21 watts, placing it in the single-filament category of automotive signal bulbs.
The bulb produces amber light natively, meaning its glass envelope is tinted rather than relying on a colored lens to achieve the required signal color.
The PY21W uses a BAU15s bayonet base, which features offset pins to prevent incorrect installation of a clear or non-amber equivalent such as the P21W, which shares the same wattage but uses a symmetrical BA15s base.
The PY21W is governed by ECE regulations, a standard adopted across Europe and numerous other markets worldwide, which mandates the amber coloring be inherent to the bulb itself.