Factory headlight setup not identified

2018 Audi A4 Headlight Bulbs & Lighting Guide

Choose the factory headlight system below to see the correct bulb and recommendation path for this 2018 Audi A4.

Source-listed fitment data supplied by CarBulbGuide. Confirm the installed bulbs and configuration before ordering.

Low beam
Factory halogen system
High beam
H11
Factory setup
Factory headlight setup not identified

Choose the factory system installed in this vehicle. Bulb sizes and recommendations change with that selection.

2018 Audi A4 representative vehicle image

Best headlight upgrades

These products were physically tested by BulbFacts, but the tests were not performed in this exact vehicle unless a card explicitly says otherwise.

Factory headlight setup not identified

High Beam: H11

OSRAM Night Breaker 200 manufacturer product image
Best direct replacement

OSRAM Night Breaker 200

High Beam H11

Estimated price$20-34
BulbFacts testedCorrect bulb size
Best Standard Reflector Upgrade

The Night Breaker 200 is the top standard-wattage reflector recommendation at the time of review. Anything scoring higher in the reflector chart uses much higher wattage, while the NB200 keeps the simple drop-in halogen format.

Measured vs stock halogenReflector test
High beam+50% light
Stock 876 lux · Upgrade 1,312 lux
Color3,550K 125K cooler
Stock 3,425K · Upgrade 3,550K · 5000K pure white
General BulbFacts housing test
Read BulbFacts reviewCompare test resultsBuy at eBay
Morimoto 2Stroke 4.0 manufacturer product image
Best reflector LED upgrade

Morimoto 2Stroke 4.0

High Beam H11

Estimated price$178
BulbFacts testedCorrect bulb sizereflector housing only
Safest Glare + DRL Pick

The glare-control recommendation for reflector housings, and also the easiest pick when your vehicle needs an LED that can properly dim for DRL use.

Measured vs stock halogenReflector test
High beam+114% light
Stock 876 lux · Upgrade 1,872 lux
Color5,250K 1,825K cooler
Stock 3,425K · Upgrade 5,250K · 5000K pure white
General BulbFacts reflector test
Read BulbFacts reviewCompare test resultsBuy at BRI Source
Morimoto XB Elite 2.0 manufacturer product image
Best projector HID upgrade

Morimoto XB Elite 2.0

High Beam H11

Estimated price$311
BulbFacts testedCorrect bulb sizeprojector housing only
Best Premium Distance

The Morimoto XB Elite remains the premium performance benchmark from the current HID recommendations. It tested as one of the strongest 35W projector-focused HID kits and is the better fit when you want a complete, higher-quality conversion kit instead of a generic marketplace option.

Measured vs stock halogenProjector test
High beam+230% light
Stock 935 lux · Upgrade 3,088 lux
Color5,000K 1,575K cooler
Stock 3,425K · Upgrade 5,000K · 5000K pure white
General BulbFacts projector test
Read BulbFacts reviewCompare test resultsBuy at BRI Source

A matching bulb size identifies fitment; it does not by itself prove optical compatibility or make a conversion a vehicle-specific recommendation. Use the LED upgrade path only with a reflector housing and confirm beam pattern and glare after installation. Use the HID upgrade path only with a projector housing; it is not a reflector-housing recommendation.

Other bulbs

Available exterior and interior lighting data for this model year.

Brake Light
1156Possible fitment — verify installed bulb
Cornering Light
H11Possible fitment — verify installed bulb
Fog Light
T15Possible fitment — verify installed bulb
Front Turn Signal
64132Verify installed bulb
Glove Box Light
2821Verify installed bulb
Tail Light
T15Possible fitment — verify installed bulb
Turn Signal (Unqualified)
BAU15SPossible fitment — verify installed bulb
Front Turn SignalLighting: HID
PW24WLikely fitment
Cornering LightModel: allroad; Lighting: HID
H11Likely fitment
Front Turn SignalModel: allroad; Lighting: HID
PW24WLikely fitment
Brake LightModel: allroad
T15Likely fitment
Fog LightModel: allroad
T15Likely fitment
Tail LightModel: allroad
T15Likely fitment
Turn Signal (Unqualified)Model: allroad
BAU15SLikely fitment
Brake LightModel: Quattro
1156Likely fitment
Cornering LightModel: Quattro
H11Likely fitment
Fog LightModel: Quattro
T15Likely fitment
Front Turn SignalModel: Quattro
PW24WLikely fitment
Tail LightModel: Quattro
T15Likely fitment
Turn Signal (Unqualified)Model: Quattro
BAU15SLikely fitment
Technical details and sources

Confirm the installed bulb, connector, housing, and factory system before ordering.

PositionBulb or systemFitment status
High BeamFactory system not specifiedH11Possible fitment — verify installed bulb
High/Low Beam CombinedLighting: HIDD5SLikely fitment
High/Low Beam CombinedModel: allroad; Lighting: HIDD5SLikely fitment
High BeamModel: allroadH11Likely fitment
High BeamModel: QuattroH11Likely fitment
High/Low Beam CombinedModel: QuattroD5SLikely fitment

Each model year opens its own BulbFacts record. Bulb sizes and factory systems are not carried over from adjacent years.

Fitment note: Verify the installed bulb, connector, housing, and factory system before ordering. A bulb-size match is not automatically a conversion recommendation or proof of vehicle-specific testing.