The Volvo WC uses a P21W bulb size for front turn signal applications and a 1156 bulb size for rear turn signal applications. The replacement chart covers vehicle production years spanning 1996 to 1998 with corresponding bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Volvo WC uses P21W bulbs in the front turn signals and 1156 bulbs in the rear turn signals across the 1996-1998 model years.
P21W is an ECE-standard bulb used primarily in European and worldwide automotive markets, while the 1156 follows the ANSI standard common to the US and Canadian markets.
Despite originating from different standardization systems, both the P21W and 1156 are electrically identical, each rated at 12V and 21W with a single filament.
Both bulb types share the BA15s bayonet base, a single-contact base design where the "s" denotes a single pin offset to one side of the base.
Because the P21W and 1156 share the same BA15s base and identical voltage and wattage ratings, they are physically and electrically interchangeable in many applications, though fitment should be confirmed against the specific socket housing of the Volvo WC.
The single-filament construction of both bulbs means each serves only one lighting function per socket, which is consistent with their use in dedicated turn signal positions rather than combined stop and turn applications.