BMW 318i License Plate Bulb Size

The BMW 318i license plate component requires a DE3423 bulb size for proper illumination and visibility on the rear of the vehicle. Available data for the specified lighting equipment covers the period from 1984 through 1998.

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
1993-1998	DE3423
1991	DE3423
1984-1985	DE3423

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 41mm length, end-cap contacts. 12V.	DE3423

Other Locations

Additional Notes

The BMW 318i uses the DE3423 bulb for its license plate lighting across all listed model years from 1984 to 1998.
The DE3423 is a festoon-type bulb, meaning it is cylindrical in shape and makes electrical contact through metal caps at each end rather than through a base socket or pins.
The DE3423 has a 41mm length, which is the span between its two end caps and determines physical fitment within the license plate lamp housing.
The bulb operates at 12 volts, consistent with the standard electrical system voltage found in passenger vehicles.
The DE3423 designation follows ANSI standards, indicating the bulb meets defined performance and dimensional criteria recognized in both the United States and Canada.
Because festoon bulbs rely on contact pressure from the housing clips rather than a keyed base, substituting a festoon bulb of a different length risks poor contact or physical incompatibility with the BMW 318i license plate lamp housing.