Mini Cooper Turn Signal Bulb Size

Additional Notes

• The P21W bulb is the most consistently used type across the Mini Cooper's turn signal specifications, serving as the rear turn signal bulb for every model year from 2002 through 2024. It is a single-filament signalling bulb rated at 12V and 21W, fitted with a BA15s bayonet base, and built to ECE standards for use in European and worldwide markets.
• The PY21W bulb served as the front turn signal bulb on the Mini Cooper from 2002 through 2013. Like the P21W, it is a single-filament 12V, 21W ECE-standard bulb, but it differs in two key ways: it produces an amber-tinted output by design, and it uses a BAU15s bayonet base rather than the straight BA15s base found on the P21W. These two base types are not interchangeable.
• From 2014 onward, the Mini Cooper front turn signal moved away from the PY21W to either the PW24W or PWY24W, depending on the lens color of the vehicle. Both of these bulb types use a wedge-pin base rather than a bayonet base, making them physically incompatible with the socket used by the earlier PY21W.
• The PW24W is specified for 2014-2024 Mini Cooper front turn signals fitted with an amber lens and without LED headlights. It is a single-filament 12V, 24W ECE-standard bulb with a WP3.3x14.5-3 wedge base. Because the lens itself provides the amber color, the bulb produces clear light.
• The PWY24W is specified for 2014-2024 Mini Cooper front turn signals fitted with a white lens under option code S785A, also without LED headlights. It shares the same 12V, 24W rating as the PW24W but uses a WP3.3x14.5-4 base and is an amber-tinted bulb by construction, compensating for the clear lens to meet signalling color requirements.
• The WP3.3x14.5-3 base of the PW24W and the WP3.3x14.5-4 base of the PWY24W are distinct pin configurations. Substituting one for the other in a given socket is not supported by these specifications.
• All four bulb types covered in these specifications, the PW24W, PWY24W, PY21W, and P21W, are rated at 12 volts and conform to ECE standards, reflecting their design for European and international vehicle lighting regulations.
• The front turn signal specifications for 2014-2024 apply only to vehicles without LED headlights. Vehicles equipped with LED headlights are outside the scope of these bulb size entries entirely.
• Similarly, the rear turn signal P21W specification for 2014-2024 applies only to vehicles without LED taillights, while the same P21W specification for 2002-2013 carries no such conditional note.
• The transition from the 21W PY21W to the 24W PW24W and PWY24W at the front turn signal position in 2014 represents a wattage increase of approximately 14 percent, which is relevant when assessing socket and wiring compatibility during any bulb replacement on affected model years.