MG Midget front turn signal bulbs use 1157 size, while rear turn signal bulbs accommodate 1156 or 1157 size specifications. The replacement chart covers vehicle production spanning 1969 to 1979.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The MG Midget uses two distinct bulb types across its turn signal positions: the 1157 and the 1156, both of which are ANSI-standardized bulbs recognized in the United States and Canada.
The 1157 is a dual-filament bulb rated at 12V with a 21W main filament and a 5W secondary filament, mounted on a BAY15d bayonet base. The dual-filament design allows a single bulb to serve two lighting functions simultaneously.
The 1156 is a single-filament bulb rated at 12V and 21W, mounted on a BA15s bayonet base. It is dedicated to a single lighting function, unlike the dual-filament 1157.
The BAY15d base of the 1157 and the BA15s base of the 1156 are not interchangeable. The BAY15d has offset pins to prevent incorrect installation, while the BA15s has a single-contact, symmetrical pin arrangement.
The front turn signal position on the MG Midget uses the 1157 bulb across all listed model years from 1969-1979.
The rear turn signal position on the MG Midget uses the 1157 bulb for model years 1969-1975, then transitions to the 1156 for model years 1976-1979.
Because the rear turn signal shifted from the dual-filament 1157 to the single-filament 1156 in 1976, installing a 1157 in a 1976-1979 rear socket, or a 1156 in a 1969-1975 rear socket, would represent a fitment mismatch relative to the original specification.