The Mercedes-Benz 190E uses a P21/5W bulb size for front turn signals and a P21W bulb size for rear turn signals. The replacement chart covers vehicle production spanning 1984 to 1993.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Mercedes-Benz 190E uses two distinct bulb types across its front and rear turn signal positions: the P21/5W for the front and the P21W for the rear, both conforming to ECE standards recognized in Europe and worldwide.
Both the P21/5W and P21W operate on a 12-volt electrical system, which is standard for passenger vehicles of this era.
The P21/5W is a dual-filament bulb, meaning it carries two separate filaments within a single envelope, rated at 21 watts and 5 watts respectively. This allows it to serve more than one lighting function from a single housing.
The P21W is a single-filament bulb rated at 21 watts, dedicated to one lighting function per position.
The P21/5W uses a BAY15d bayonet base. The offset pins on a BAY15d base are positioned at different heights, which physically prevents incorrect insertion and ensures the correct filament is aligned with the intended circuit.
The P21W uses a BA15s bayonet base, a single-contact fitting with symmetrically placed pins. Because the P21W and P21/5W use different base types, the front and rear turn signal bulbs are not interchangeable with each other.
The front turn signal position of the Mercedes-Benz 190E requires the P21/5W across all model years covered in the specifications, spanning 1984-1993.
The rear turn signal position requires the P21W across the same 1984-1993 span, with no variation by year.