Mercedes Sprinter D3S Xenon Headlight Bulb – Flosser | NCV3 | #N10721801

A burnt-out D3S xenon bulb on a NCV3 Sprinter leaves the headlight dark — even with a functioning ballast, no xenon arc means no forward illumination at night and a failed headlight inspection. This is the Flosser D3S xenon headlight bulb for NCV3 Sprinters and other Mercedes-Benz vehicles equipped with D3S xenon headlights, a direct replacement that restores the high-intensity discharge arc and proper white light output.

What This Part Does

The D3S is a high-pressure xenon discharge bulb with an integrated igniter — the "S" designation indicates it has a built-in starter that works with the external ballast to strike and sustain the xenon arc. The bulb contains xenon gas and a precise mixture of metal halide salts in a quartz arc tube. When the ballast delivers the high-voltage strike pulse, an arc forms between the tungsten electrodes and ionizes the gas mixture, producing the brilliant white-blue light characteristic of HID xenon systems. The D3S produces approximately 3,200 lumens compared to roughly 1,550 lumens for a standard H7 halogen — a significant improvement in road illumination. Over time, the electrodes erode, the arc tube glass darkens from tungsten deposition, and light output drops progressively before the bulb eventually fails to strike reliably.

Common Symptoms of a Failing D3S Xenon Bulb

• Headlight that does not illuminate after the ballast and wiring are confirmed good
• Headlight that requires multiple attempts to strike before staying on
• Noticeably yellowed, reduced, or flickering light output compared to the other side
• Headlight that starts but shuts off within seconds from insufficient arc current

When to Replace

Replace when the bulb fails to illuminate or produces noticeably degraded output with the ballast confirmed working. Always replace xenon bulbs in pairs — a new bulb alongside an aged one produces a visible color and brightness mismatch that is distracting and unprofessional. Never touch the quartz arc tube with bare fingers.

Fitment

• NCV3 Mercedes-Benz Sprinter with D3S xenon headlights (2010–2018)
• Other Mercedes-Benz and compatible vehicles with D3S xenon headlight systems

✔ D3S with integrated igniter — confirm your headlight uses D3S before ordering
✔ Always replace in pairs — left and right headlights
✔ Do not touch quartz glass with bare fingers during installation

Part Numbers

• Mercedes N-part: N10721801
• Cross-reference: D3S / 35W / PK32d-5
• Manufacturer: Flosser — 42322
• SKU: N10721801