Mercedes-Benz GLC43 AMG Back Up Light Bulb Size

The Mercedes-Benz GLC43 AMG back up light requires a bulb size of 921 for proper installation and function within the rear lighting assembly. Data for the specific component covers a range from 2017 through 2022.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
2017-2022	921

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Wedge bulb (T15). 12V, 16W.	921

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Additional Notes

The 921 bulb is the specified back up light bulb size for the Mercedes-Benz GLC43 AMG across the 2017-2022 model years.
The 921 is an ANSI-standardized bulb type, meaning its physical and electrical specifications conform to a defined industry standard recognized in the United States and Canada.
The 921 uses a wedge-style base, designated T15, which refers to a tubular bulb body approximately 15 eighths of an inch wide that is held in its socket by friction rather than by pins or a bayonet mechanism.
The bulb operates at 12 volts and draws 16 watts, consistent with standard automotive low-voltage electrical systems.
The wedge base design of the T15 means the bulb is not interchangeable with pin-base or bayonet-base types, even when voltage and wattage ratings are otherwise similar.