Guide: Which bulb should I choose for my car?
How to choose your car bulb?
This comprehensive guide helps you identify the right bulb for each light on your vehicle. First step: identify the type of light (sidelight, dipped beam, main beam, fog light, etc.) and consult your car's manual for the exact reference. The type, wattage (W) and voltage (V) are also marked on the bulb.
Sidelights — parking lights
Sidelights or "parking lights" improve the visibility of your vehicle. At night or in poor visibility, it is mandatory to switch to dipped beam headlights.
2 symmetrical pins. BA15s cap 15 mm. Also available in R10W (10W).
Capless, "Wedge Base" T10. Diameter 10 mm. Power 5W.
Symmetrical pins. BA9s cap 9 mm. Power 4W.
Dipped beam headlights — "Low beams"
Dipped beam headlights are the main lighting of the vehicle (up to several tens of meters ahead). Mandatory at night and in bad weather. Standard power: 55W.
Halogen double filament (60/55W). Dipped + main beam in a single bulb. P43t base.
Halogen single filament. 55W. PX26d base. Dipped or main beam.
Halogen single filament. 55W. P14.5s base. Dipped or main beam.
European code — older cars (until late 80s).
Modern cars. PGJ19-2 base.
D1S, D2S, D3S, D4S — high-end cars.
Turn signals
Common power: 21W. The most common is P21W, but PY21W and H21W also equip many vehicles.
Symmetrical pins. BA15s cap 15 mm. The most common.
Offset pins. Often orange. BAU15s cap.
Capless. Diameter 20 mm (T20).
BAY9s cap 9 mm. Offset pins.
Orange version. BAW9s cap.
Capless T15, 15 mm diameter, orange.
Rear lights / Brake lights
Double filament bulbs, generally 21/5W power. The most common: P21/5W.
BAY15D cap. 21W brake, 5W rear.
Capless T20, 20 mm diameter.
Offset pins 2 directions. BAZ15d cap.
Main beam headlights — "High beams"
Complementary to dipped beam headlights, used in cases of poor visibility at night. Max power: 60W. Common bulbs: H4, H7, H1, H3.
Fog lights
Front fog lights — not mandatory, to be used only in case of fog, snowfall or heavy rain. Common bulbs: H1, H7, H2 X511, H8 PGJ19-1.
Rear fog lights — only in case of fog and heavy snowfall. Bulbs: H21W (BAY9s), P21W (BA15s). See collection.
Reversing lights
Same bulbs as for turn signals: P21W (BA15s), W21W (T20), H21W (BAY9s). See collection.
Reference chart: which bulb for which light?
Changing a car bulb
- Consult the manual to identify the bulb type.
- Without a manual: remove the burnt-out bulb and note its type, wattage (W) and voltage (V).
- Front: open the hood, remove the connector then the retaining clip.
- Rear: open the trunk and unscrew the light unit bolt.
- Never touch the glass of a halogen bulb with your fingers (use gloves or a clean cloth).
- Check that it works properly before closing everything.
👉 Consider a spare bulb kit in the glove compartment — avoids a fine of €68 to €135.
Color temperature (in Kelvin)
Color temperature is expressed in Kelvin (K). A standard halogen emits a yellow-white light around 3,200 K. "Super White" and "Pure White" bulbs are closer to daylight (4,000–5,000 K). LEDs and Xenon often exceed 6,000 K.
Regulations
Only install approved bulbs (fine of €135, reduced to €90). Headlights must be switched on as soon as visibility drops below 150 m. Fog lights are prohibited in normal rain.
Before a technical inspection, check all lights: dipped/main beam, sidelights, turn signals, hazard lights, brake lights, license plate lights. A burnt-out bulb = re-inspection required.