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full bulletin at NHTSA ↗2005 Audi S4 lighting problems
moderate 31 complaints filed with NHTSA · avg repair $250 · see lighting across all vehicles →
Failure mileage
Complaints
31
Recalls
0
Avg fix
$250
When does it fail?
Of the 31 lighting complaints filed for the 2005 Audi S4, here's the actual mileage breakdown — failures cluster heaviest at 25,000-50,000 mi.
0-25k
25-50k
50-75k
75-100k
100-125k
125-150k
150k+
Each bar shows the share of total complaints filed at that mileage range. Peak failure window highlighted. Some owners report problems earlier; some make it well past 150,000 miles symptom-free. Maintenance habits and driving conditions shift the curve as much as mileage alone.
How fast does it fail?
Cumulative share of the 12 mileage-bearing lighting complaints filed against the 2005 Audi S4 by each odometer reading. Median failure: 60,438 mi.
10% have failed by40,000 mi
Half the fleet by60,438 mi
90% have failed by106,250 mi
Curve based on owner-reported odometer mileage at the time of complaint. Reflects when owners filed, not when symptoms first appeared. Maintenance habits and driving conditions shift the curve.
What stands out
Lighting accounts for 72% of every owner complaint on file for this vehicle — the dominant problem area across 3 categories tracked.
Owners have filed 31 lighting complaints with NHTSA against this vehicle, but no formal recall covers the issue — the federal record reflects what manufacturers have admitted, not everything owners are reporting.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering lighting on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
This informational bulletin contains technical information for when there is condensation visible on the inside of the headlight, taillight, fog light, side marker light, front turn signal, daytime running lights, and/or third brake light lens.
full bulletin at NHTSA ↗Supersedes Technical Service Bulletin Group 94 number 12-92 dated October 24, 2012. Condensation is visible on the inside of the headlight, taillight, fog light, side marker light, front turn signal, daytime running lights, or third brake light lens.
full bulletin at NHTSA ↗Supersedes Technical Service Bulletin Group 94 number 11-52 dated October 11, 2011. Condensation is visible on the inside of the headlight, taillight, fog light, side marker light, front turn signal, daytime running lights, or third brake light lens. Damp air settles on the inside of a cold lens, which creates condensation. The headlight circulation system allows air from the outside to flow through the headlights. This open waterprotected ventilation system (needed for pressure compensation) creates different climate zones in the headlight: very warm areas, where the lens is warmed up by the light, and relatively cool areas, where the lens is cooled own by the air flow. Considerable differe
full bulletin at NHTSA ↗HEADLIGHT AIMING, USING HELLA UNIVERSAL BEAMSETTER.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
The 2005 Audi S4's bi-xenon HID headlights are the dominant complaint across 31 narratives. The primary failure is intermittent flickering followed by complete shutdown while driving, with a "Dipped Headlight" error appearing on the dash. Owners report the lights restore only by cycling the headlight switch off and back on—sometimes requiring multiple cycles per 30-minute drive. The problem occurs at any speed, worsens during cold starts, deceleration, bumpy roads, and non-flat terrain. Flickering creates a dangerous strobe effect that confuses oncoming traffic and pedestrians. Dealers consistently claim they cannot replicate the issue despite it occurring immediately during test drives. Bulb and ballast replacements don't fix it; even full headlight assembly replacements fail to resolve the recurring failure. Some owners have been cited by police for non-functioning lights and face vehicle inspection failures.
A secondary issue affects many units: condensation or standing water inside the headlight lens that persists indefinitely, reducing output and visibility in wet conditions. Audi refuses warranty repair, claiming condensation is normal due to assembly vents. Owners report a TSB exists but dealers won't apply it under CPO warranty. One incident of reflector failure causing dimness at 70,000 miles was also documented.
Same Audi S4 lighting reports on nearby years: 2006
Failure modes owners describe
HID Headlight Flickering and Shutoff
Bi-xenon HID headlights flicker, dim, and shut off while driving. Error message 'Dipped Headlight' (left or right) appears on dash. Lights can be temporarily restored by cycling the headlight switch off and back on. Problem recurs and may worsen over time with repeated cycling needed per drive.
When: Intermittent; occurs more frequently right after lights are switched on, on non-flat roads (inclines/declines), during cold starts, deceleration/braking, and in cold weather. Can occur at any speed.
Symptoms owners cite: Headlight flickers then dims then shuts off; Error message 'Dipped Headlight' or 'Left/Right Headlight Dipped' on dash; Requires headlight switch cycling to restore light temporarily; Flickering creates dangerous visual confusion for oncoming traffic; Can occur during idle, acceleration, turning, or deceleration
Codes mentioned: Dipped Headlight warning
Repairs/costs cited: Dealers unable to replicate problem on service visits. Bulbs replaced without effect. Ballasts replaced without resolving issue. Entire headlight assemblies replaced; problem persists. Visual inspection of electrical connections performed without resolution.
Recalls/TSBs owners mention: Audi denies warranty coverage; claims inability to replicate. No TSB or formal recall issued; owners report TSB mentioned by some dealers but not applied.
Headlight Condensation and Water Accumulation
Water or condensation accumulates inside headlight lens assembly, reducing light output and visibility. Occurs after any precipitation or moisture exposure. Does not dry out on its own even in dry weather. Problem is persistent and degrades headlight effectiveness.
When: After rain, snow, or humid conditions. Can occur at low mileage (30,000 miles reported).
Symptoms owners cite: Heavy condensation or water droplets inside headlight lens; Reduced visibility at night; Headlight appears unclear even when on; Problem worsens in rain or fog conditions
Repairs/costs cited: Dealer suggested running lights for one hour or using hair dryer to dry headlights. Attempted re-sealing did not resolve. No permanent repair documented.
Recalls/TSBs owners mention: Audi claims condensation is normal due to vents in HID headlamp assembly and refuses to remedy. Some owners report TSB exists but dealers refuse to apply under CPO warranty. No recall issued.
Headlight Reflector Failure
Headlight reflector degrades, causing headlights to become dim with low visibility despite lamps functioning.
When: Reported at 70,000 miles.
Symptoms owners cite: Headlights become dim; Low visibility output despite light being on
Repairs/costs cited: Diagnosed at dealer. Vehicle not repaired.
Synthesized from 31 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 13 most recent
I just purchased a 2005 Audi s4 with only 30,000 miles. The car is in exceptional condition and I am very pleased. However, both headlight units contained considerable condensation. It seriously reduces my ability to clearly see at night. Last night was the first time I had to use my lights and I had to keep checking to see if they were on. After discussing the issue with my local Audi…
The xenon headlights in my s4 go out as the car is in motion. The light may flicker. The headlight may "dip." the light shuts off and I have to stop the car and shut off the lights and then turn them back on for the light to reignite. The bulb and control unit was replaced under warranty. Now two years later the same thing is happening. It seems to be a very common problem with Audi's…
My car is a 2005.5 Audi s4 with bi-xenon HID headlights. I almost always get a dipped headlight error whenever I turn on the headlights. It occurs more often on the driver's side headlight. This will randomly happen but I have noticed that it occurs more frequently right after the headlights are switched on. It will also happen when the road is either on an incline or decline, or really when the…
Takata recall 1. The left headlight flickers. 2. It then turns itself off 3. The message "left dipped headlight" appears 4. This happens while my vehicle is parked and in motion so it is a very serious safety risk. I have had both headlights go out at night while driving with my 2 year old in the car!
2005 Audi s4 - experiencing "dipped headlight" error where the headlights flicker then shut off while driving. The headlight can be turned back on only if the headlight switch is turned off then turned back on. This corrects the problem temporarily, with the headlight flickering again then shutting off. The problem is persistent and is a safety issue. Took my car to Audi dealer but they could…
Car has a problem with its headlights completely covered with condensation inside, therefore cutting on the amount of light from headlights. Audi refused to offer any help to remedy this problem, therefore making driving in the dark very dangerous.
Tl* the contact owns a 2005 Audi s4. The contact stated that while driving 70 MPH, the headlights became dim with low visibility. The vehicle was taken to a dealer and the headlights were diagnosed with having a reflector failure. The vehicle was not repaired and the manufacturer was been of the issue. The approximate failure mileage was 70000.
I have a 2005 Audi s4 and my headlights flicker and go out while driving almost every time I have them on. Sometimes it is one and sometimes both and I get a message on my dash board that the affected headlight is dipped. If I turn the lights off then back on the affected headlight will usually come back on. Sometimes that doesn't work and the car has to be turned off and restarted. Headlights…
My car is a 2005.5 Audi s4. When I drive at night, the headlights turn off at random. It will sometimes be one, but tonight both went out. It occurs every night I drive the car. The bulbs have been replaced, the ballasts and the dealer was unable to duplicate. *tr
Tl* the contact owns a 2005 Audi s4. The contact stated that while driving approximately 10 MPH, the headlights began to flicker and suddenly shut off. The vehicle was stopped and shut off. After restarting, the headlights functioned properly. The failure occurred intermittently and occurred while parked or while driving at different speeds. The vehicle was taken to an independent mechanic, where…
Had lighting trouble with your 2005 Audi S4?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the lighting problem on the 2005 Audi S4?
It's a documented issue but not catastrophic. 31 complaints have been filed. Repairs average $250 and most owners catch it before it causes a breakdown.
At what mileage does the lighting typically fail?
Across the 24 complaints that reported odometer mileage, most lighting failures cluster between 40,000 and 74,000 miles, with the median around 57,000. A quarter of owners report trouble before 40,000; a quarter make it past 74,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $250 for lighting repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to lighting?
No active recalls currently cover lighting issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2005/Audi/S4.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.