The Jaguar XJ6 front turn signal requires a P21W bulb size, while the rear turn signal uses either a PY21W or 1156 bulb size. The replacement chart covers 1972 to 1997 production years 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 1157 bulb is the most frequently specified front turn signal bulb across the Jaguar XJ6 range, appearing in model years 1973-1994 with the exception of 1972. It follows the ANSI standard and carries a dual-filament design rated at 12V with a 21W main filament and a 5W secondary filament, mounted on a BAY15d bayonet base.
The 1156 bulb holds the same dominant position in the rear turn signal position, covering model years 1972-1994. Unlike the 1157 used at the front, the 1156 is a single-filament bulb rated at 12V and 21W, sharing the BA15s bayonet base with the P21W.
Despite the 1157 and 1156 both operating at 12V and 21W, they are not interchangeable. The 1157 uses a BAY15d base with offset pins to accommodate its dual-filament design, while the 1156 uses a BA15s base with a single contact. Substituting one for the other is not possible without modification.
For the 1995-1996 Jaguar XJ6, the front turn signal retains the P21W bulb, while the rear turn signal shifts to the 12496, a Philips/Osram part number designating a specialty halogen application at 12V. The 12496 does not share a standardized ANSI or ECE classification with the other bulbs in these specifications.
The P21W is an ECE-standard single-filament bulb rated at 12V and 21W with a BA15s bayonet base. It appears at the front turn signal position for the 1972 and 1995-1997 XJ6 model years, reflecting a shift away from the ANSI-standard 1157 used in the intervening years.
The 1997 Jaguar XJ6 rear turn signal specifies the PY21W, which differs from all other bulbs in these specifications by being an amber-tinted bulb. It uses a BAU15s base, which has an offset pin arrangement distinct from both the BA15s and BAY15d bases, making it physically incompatible with sockets designed for P21W or 1156 bulbs.
The front and rear turn signal positions on the 1997 XJ6 use different ECE-standard bulbs: P21W at the front and PY21W at the rear. Although both are rated at 12V and 21W, their base types differ, and the amber coloring of the PY21W is built into the bulb itself rather than the lens.
A notable fitment boundary exists at the 1994-1995 model year transition. The front turn signal changes from the ANSI 1157 to the ECE P21W, and the rear changes from the ANSI 1156 to the 12496. These two standards use different base configurations, so bulbs from the pre-1995 and post-1994 specifications are not cross-compatible.
The BA15s base is shared by both the P21W and the 1156, meaning the base geometry alone does not distinguish these two bulbs. However, the P21W is an ECE-classified bulb while the 1156 follows the ANSI standard, and the two are sourced through different supply chains despite their physical similarity.
Across all specified years, the Jaguar XJ6 front and rear turn signal positions never share the same bulb type within a given model year, reflecting a consistent design separation between the single-contact rear application and the varying front specifications.