The Cadillac Cimarron front turn signal requires a 1034NA, 1157NA, or 1157 bulb size, while the rear turn signal uses a 1156 or 1157 bulb size. The replacement chart covers vehicle production spanning 1982 to 1988 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.
The 1157NA bulb is the most frequently specified front turn signal bulb across the Cadillac Cimarron's production run, appearing in the 1984-1985 and 1987 model years.
The 1157NA is a dual-filament bulb rated at 12V and 21W/5W, fitted with a BAY15d bayonet base and natural amber glass, meeting ANSI standards for the US and Canada.
The natural amber glass on the 1157NA produces an amber output directly from the bulb, without relying on a colored lens to achieve the required turn signal color.
The 1034NA, used on the Cadillac Cimarron front turn signal in 1982 and 1988, shares the same BAY15d bayonet base and natural amber glass as the 1157NA but is rated at 12V and 21/5W, and is classified as a variant of the 1157.
The 1157 bulb, used on the front turn signal in 1986 and the rear turn signal in 1983-1984 and 1986, is electrically identical to the 1157NA at 12V and 21W/5W with a BAY15d base, but lacks the natural amber glass coating.
The 2057NA, specified for the 1983 front turn signal, is a brighter dual-filament bulb rated at 12V and 26.9W/8W. It uses the same BAY15d bayonet base as the 1157NA but draws more power on both filaments.
The rear turn signal for the 1985, 1987, and 1988 model years uses the 1156, a single-filament bulb rated at 12V and 21W with a BA15s bayonet base.
The BA15s base on the 1156 and the BAY15d base on the dual-filament bulbs are not interchangeable. The BAY15d base has offset pins to prevent incorrect installation of a dual-filament bulb in a single-filament socket.
The front and rear turn signal positions on the Cimarron do not consistently use the same bulb type within a given model year, as seen in 1986 where both positions use the 1157, while in 1985 the front uses the 1157NA and the rear uses the 1156.
The shift from a dual-filament rear bulb in 1982-1984 to a single-filament 1156 in 1985 reflects a change in how the rear lighting circuit was configured, since a single-filament bulb serves only one function rather than sharing a filament with another lighting mode.