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Show all 13 variants
At a glance
- Years: 2018 to 2025; facelift in 2023. Saloon, Avant and allroad.
- Reliability: 3/5. The 48 V belt starter-generator is a costly failure on 2018-2020 cars, and early infotainment is glitchy.
- DIY: 1/5. The 48 V system and the software work need an Audi dealer with the ODIS diagnostic tool.
- Prefer: a 2021 or later car with a full Audi service history and proof of the generator and software updates.
- Avoid: 2018-2020 cars without proof of a generator repair or the latest software.
Engines and gearboxes
- 2.0 TDI EA288 evo (DEZ, DFB, DTP), 2018-2025: 163 and 204 PS. See the EA288 guide.
- 3.0 TDI V6 (DDV, DMG), 2018-2025: 231 to 286 PS. The 50 TDI can hesitate when pulling away; a software update is the fix.
- S6 TDI (DEW, DMK), 2019-2025: 344 to 350 PS. It shares the pull-away hesitation; a software update is the fix.
- 2.0 TFSI (DKN, DMT), 2018-2025: 245 and 265 PS. See the EA888 guide.
- 3.0 TFSI V6 (DLZ), 2018-2025: 340 PS. No fault confirmed in the sources read.
- Plug-in hybrid 50 and 55 TFSI e (DLG, DRY), 2019-2025: 299 and 367 PS. No fault confirmed in the sources read.
- RS6 4.0 TFSI V8 (DJP, DYG), 2019-2025: 600 and 630 PS. No fault confirmed in the sources read.
- 7-speed S tronic DL382: See the DL382 guide.
- 8-speed tiptronic: no A6-specific fault confirmed in the sources read.
Known issues
| Issue | Affects | Typical km | Repair cost |
|---|---|---|---|
| 48 V belt starter-generator failure | Cars built 2018-2020, several engines | Not stated | 1,190-2,300 EUR (ADAC, Germany, year not stated) |
| MMI and infotainment faults | Early cars, about 2018-2020 | Not stated | No confirmed price |
| Sluggish pull-away on the 3.0 TDI V6 | 3.0 TDI V6 (DDV, DMG) and S6 (DEW, DMK) | Not stated | No confirmed price |
Before you buy
- 48 V belt starter-generator: on a 2018-2020 car, start it from cold and look for a network warning. This check needs a scanner; a dealer with ODIS should read the generator and 48 V battery faults. Bad: a yellow or red network message, a warm idle stuck near 1,000 rpm, or start-stop switched off.
- MMI and screens: test both screens, sat nav, radio, climate and driver-assist systems together. Ask for the software version and the date of the last update. Bad: a screen that freezes, lost favourites, or a warning that cruise control is not available.
- 3.0 TDI pull-away: drive a 50 TDI or S6 from a stop and at low speed. Bad: a long hesitation before the car moves. Ask whether the engine and gearbox software updates were done.
- Recalls: ask an Audi dealer to check open campaigns by VIN, especially the panoramic roof, passenger airbag and rear axle campaigns.
Running costs
| Operational | €231 |
|---|---|
| Workshop | €178 |
| Fixed costs (tax, insurance) | €232 |
| Total per month | €641 |
| New-car depreciation (not included) | €122 |
ADAC figures for 15,000 km a year over 60 months
Market
Listings on mobile.de priced up to 50,000 EUR, 29 October 2026.
- Listings
- 5,568
- 25th percentile
- €25,990
- Median price
- €29,980
- 75th percentile
- €35,380
- Median mileage
- 93,002 km
- Median first registration
- 2022
- Dealer share
- 89.9%
- Price at 100,000 km
- €31,201
To check a listing's price, open its variant in the table above. Each variant page has a price check.
In detail
48 V belt starter-generator failure
Symptoms. A yellow, then red, on-board network warning. The engine can hold about 1,000 rpm when warm, then stall and drop into neutral. Start-stop stops working. Owners on DRIVE2 report these signs.
Cause. Moisture in the mild-hybrid system. wheelstreet.lt ties it to a specific production batch. One DRIVE2 owner reports that the workshop found oxidised contacts and transistors inside the unit. The sources do not give one cause for every failure.
Which cars. Cars built from 2018 to 2020. ADAC lists the generator as a common fault in that window, and the other reports name the same years. It is not tied to one engine.
Fix. Replace the belt starter-generator. One DRIVE2 owner also renewed the belt, tensioner and roller.
Cost. ADAC puts the workshop price, with fitting, at 1,190 EUR for the 35 and 40 TDI, 1,490 EUR for the 45 and 50 TDI, 2,150 EUR for the S6, and 1,190-2,300 EUR for the petrol versions (Germany, year not stated). wheelstreet.lt puts a moisture repair at 500-1,500 EUR (year not stated).
Sources: ADAC A6 diesel, ADAC A6 petrol, gebrauchtwagenberater.de, wheelstreet.lt
MMI and infotainment faults
Symptoms. The MMI freezes or crashes and loses radio favourites and sat-nav destinations. Sometimes both screens stop, taking sat nav, radio, heating and safety features with them. Door lock actuators and sensor warnings can also appear. Owners on PistonHeads and Carbuyer report the screen faults.
Cause. Software. The sources do not name one faulty part.
Which cars. Early C8 cars, about 2018 to 2020. wheelstreet.lt says the faults are worst on early cars.
Fix. Dealer software updates. PistonHeads owners had the camera and sat-nav software updated; one Carbuyer owner was told there was no fix at the time.
Cost. No confirmed price for a screen or MMI unit.
Sources: wheelstreet.lt, gebrauchtwagenberater.de, PistonHeads, Carbuyer
Sluggish pull-away on the 3.0 TDI V6
Symptoms. A long hesitation when pulling away from a stop, and a gearbox that feels slow to respond. ADAC calls it a pronounced pull-away weakness on six-cylinder cars. One DRIVE2 owner of a 50 TDI describes a heavy lag.
Cause. The sources blame the engine and gearbox software, not a worn part. ADAC also calls the six-cylinder pull-away behaviour unrefined.
Which cars. The 50 TDI (286 PS) and the S6. ADAC reports it on six-cylinder cars; gebrauchtwagenberater.de names the 50 TDI and S6.
Fix. A software update. gebrauchtwagenberater.de says an update removed the weakness; the DRIVE2 owner had the engine and gearbox reflashed and the response became normal.
Cost. No confirmed price.
Sources: ADAC A6 diesel, gebrauchtwagenberater.de, DRIVE2
Recalls
| Country | Code | Years | What is done |
|---|---|---|---|
| Germany (ADAC); UK (Auto Express) | Not given | Built July to October 2018 (Auto Express) | The rear glass section of the panoramic roof can lose its bond, causing wind noise, leaks or a loose panel. The rear roof module is replaced. |
| Germany (KBA, via auto motor und sport and gebrauchtwagenberater.de) | 010657 | A6 and A7 built 2017 to 2020 | A dashboard manufacturing fault can stop the passenger airbag working properly and throw fragments in a crash. The dashboard is checked and reworked. |
| UK (Auto Express); Germany (gebrauchtwagenberater.de) | Not given | Built November 2019 to February 2021 | Rear axle retaining nuts or links can suffer stress corrosion and break. The rear axle is inspected, the alignment is checked, and tyres are replaced if unevenly worn. |
Check every campaign by VIN with a dealer before you buy.
Maintenance
- 48 V system: on a 2018-2020 car, have the belt starter-generator, belt, tensioner and roller checked at service.
- Software: keep the MMI and driver-assist software up to date; early cars needed dealer updates for camera, sat-nav and warning faults.
- Recalls: check open campaigns by VIN, especially the panoramic roof, passenger airbag and rear axle campaigns.
Sources
English
- Auto Express: used Audi A6 Mk5 buyer's guide
- Carbuyer: Audi A6 owner reviews
- PistonHeads: 2019 A6 C8 discussion
- PistonHeads: pre-sense and lane departure warnings
German
- ADAC: A6 2018-2025 diesel
- ADAC: A6 2018-2025 petrol
- auto motor und sport: A6 and A7 passenger airbag recall
- gebrauchtwagenberater.de: Audi A6 C8 problems
- wheelstreet.lt: is the Audi A6 a good choice?