Mercedes Sprinter Turn Signal Bulb 12V 21W Amber – Flosser | All Generations | #667101

A burnt-out turn signal bulb on a Mercedes Sprinter is an immediate safety violation and a guaranteed source of that rapid hyperflash that alerts the driver to the problem every time they signal. This is the Flosser PY21W 12V 21W amber turn signal bulb for Mercedes-Benz Sprinter vans, sold individually for front or rear turn signal replacement in lamp housings that use the standard BA15s bayonet base.

What This Part Does

The PY21W amber turn signal bulb is a single-filament incandescent lamp with an amber-tinted glass envelope, used in the front and rear turn signal positions of Mercedes Sprinter vans equipped with halogen or partial LED lighting assemblies. The amber glass coloring produces the orange-amber light required by US and international lighting regulations for turn signal functions — as opposed to clear P21W bulbs used in brake and running light positions that rely on the lens for color. The 21-watt rating provides the brightness required for clear daytime and nighttime visibility to surrounding traffic. The standard BA15s bayonet base seats and locks into the bulb socket with a quarter-turn, making replacement straightforward once the lamp housing or access panel is opened.

When a PY21W bulb burns out, the turn signal circuit loses a significant portion of its current draw — the flasher relay detects this reduced load and increases flash rate (hyperflash), which both alerts the driver and makes the remaining functioning signals flash at an abnormal rate that is itself a safety and inspection concern.

Common Symptoms of a Failed Turn Signal Bulb

• Rapid hyperflash rate on the dashboard indicator — the most reliable sign of a failed signal bulb
• One front or rear turn signal not illuminating when signaling
• Turn signal bulb confirmed dark with filament visibly broken or burnt on inspection
• Failed safety inspection for turn signal function or amber light output

When to Replace

Replace immediately when a turn signal position is confirmed dark or hyperflash is detected. Always replace in pairs — left and right for the same position — to ensure even brightness and eliminate a near-term repeat failure on the opposite side.

Fitment

• 2001–2006 Mercedes-Benz / Dodge Sprinter (T1N) – Front and rear turn signal positions
• 2007–2018 Mercedes-Benz / Dodge / Freightliner Sprinter (NCV3) – Front and rear turn signal positions
• 2019+ Mercedes-Benz Sprinter (VS30) – Front and rear turn signal positions (halogen and partial LED assemblies)

✔ 12V / 21W / PY21W / BA15s bayonet base / Amber glass
✔ Single filament — for turn signal positions only
✔ Always verify your lamp housing uses PY21W amber bulbs — full LED assemblies do not use replaceable bulbs

Part Numbers

• Manufacturer: Flosser — 667101
• Cross-reference: PY21W / BA15s
• SKU: 667101