Plymouth Horizon high beam and low beam headlight bulbs both utilize the H6054 size. The replacement chart covers vehicle production spanning 1978 to 1990.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Plymouth Horizon uses the H6054 bulb size for both high beam and low beam headlights across all model years from 1978-1990.
The H6054 is a 5x7-inch rectangular sealed beam unit, meaning the lens, reflector, and filament are fused into a single assembly rather than housing a separate replaceable bulb inside.
Because the H6054 is a sealed beam design, the entire headlight unit is replaced when the light fails, not an individual bulb within it.
The H6054 operates at 12 volts and conforms to ANSI standards recognized in both the United States and Canada.
Since the same H6054 unit serves both the high beam and low beam positions on the Plymouth Horizon, the sealed beam contains dual filaments within a single housing to produce both lighting functions.
The H6054 designation is a standardized size code, which means units from different manufacturers sharing that designation are physically interchangeable with one another in the Plymouth Horizon across the full 1978-1990 production span.