The S tronic transmission in the Audi A5 combines speed with precision, but it has specific faults that you, as an owner, need to recognise. Jerky gear changes, abrupt acceleration and a reluctant reverse gear when starting from cold are symptoms of mechatronic issues that occur mainly in the B8 generation from 2010–2016. Read on to discover which signs point to transmission trouble and what you can do about it.
common faults in the S tronic automatic
The S tronic transmission is a dual‑clutch automatic that is known for its rapid gear changes. Even so, some Audi A5 owners struggle with persistent problems. The mechatronics unit is the critical weak spot. This electro‑hydraulic control unit manages the clutch and gear selection, but can fail, especially in earlier models.
The issue often starts innocently with a warning light on the dashboard. The EPC light or the PRND symbol lights up. Jerky gear changes follow and, in serious cases, reverse gear fails completely. Some owners report that their A5 is stuck in first gear, while others say that the transmission switches to a limp‑home mode with limited functionality.
You can recognise the symptoms of mechatronic failure by several signs. The transmission may shift roughly and unpredictably, with a clear jolt when changing gear. On cold starts, reverse gear often engages reluctantly or not at all. In the worst case, gears stick completely and the automatic gearbox stops changing gear.
‘ Do not ignore these signs, because an early diagnosis prevents more serious damage. ’
what to do about jerky gear changes
Jerky shifting often develops gradually. At first you feel light jolts when changing gear, especially at low speeds. This can point to normal wear. It can also indicate early‑stage mechatronic problems. Do not ignore these signs, because an early diagnosis prevents more serious damage.
The first step is to read out fault codes (error messages from the on‑board computer) at an authorised Audi dealer. Many owners see fault codes such as P17D8 (a fault code for excessive clutch temperature). P17D6 and P17D7 (fault codes for excessive pressure in clutch 1 or 2) also occur frequently. These codes provide concrete clues about the underlying problem.
Record exactly when the jerky behaviour occurs. Does it only happen with a cold engine? Does it occur in specific gears? This information helps the mechanic to make the right diagnosis. Do not try to tinker with the transmission yourself, as these repairs require specialist equipment and expertise.
software updates as the first solution
Audi has issued various technical service bulletins (official notifications to dealers about known problems) to address common S tronic issues. A lot of jerky shifting can be resolved with a software update. These updates optimise the shift strategy (the timing and way in which the gearbox changes gear) and clutch pressure, making the driving behaviour smoother. Always have it checked first whether your vehicle has the latest firmware.
overheating and performance issues
The S tronic transmission can overheat under heavy use. This mainly happens in stop‑start traffic or when towing a trailer. Overheating leads to reduced performance and often activates limp‑home mode. In this mode, the transmission restricts itself to a few gears to prevent further damage.
The main causes of overheating are:
- Driving for long periods in heavy traffic with frequent gear changes
- Towing heavy loads without transmission cooling
- Aggressive driving with hard acceleration
- Old or contaminated transmission oil
Regular maintenance prevents many overheating problems. Ensure timely transmission oil changes in line with Audi’s recommendations. Some dealers claim that the oil lasts the lifetime of the vehicle. Real‑world experience, however, shows that changing it every 60,000 to 80,000 kilometres significantly extends the life of the transmission.
which Audi A5 models are most at risk
Not all Audi A5 models with S tronic are equally affected by transmission problems. The B8 generation from 2010–2016 shows the highest failure rates. Early versions with the 0B5 DL501 transmission in particular suffer from mechatronic faults. Performance variants such as the S5 and sporty S line versions experience more problems because the transmission is used more intensively.
Newer models benefit from improved designs and revised mechatronics. The B9 generation from 2016 onwards shows fewer faults, although no system is completely immune. When buying a used A5 from the B8 period, you need to be extra vigilant.
testing the transmission (the automatic gearbox) when buying used
Test the S tronic transmission thoroughly before you buy a used Audi A5. Start with a cold engine and pay attention to how it shifts during the first few kilometres. Reverse gear should engage immediately and smoothly, without hesitation or delay.
During the test drive, check the following:
- Does the transmission shift smoothly at different speeds
- Are any warning lights on the dashboard illuminated
- Does the clutch feel natural, without vibrations
- Does the automatic gearbox respond quickly to kick‑down manoeuvres
- Do both manual and automatic shifting work correctly
Always have fault codes read out by a specialist before purchase. Even without visible symptoms, stored codes can point to underlying issues. Ask the seller for the service history; documented transmission oil changes are a positive sign.
‘ Fortunately, there are alternative repair options. ’
repair costs and replacement options
The cost of S tronic repairs varies greatly depending on the nature of the problem. Repairing a mechatronic unit costs on average between 1,500 and 2,500 euros at a specialist workshop. Full replacement of the mechatronics runs between 3,000 and 5,000 euros, including programming (configuring and adapting the new unit to the car) and labour.
In the event of serious damage to the transmission itself, replacement may be necessary. A reconditioned S tronic transmission costs 4,000 to 7,000 euros, depending on the type and supplier. A brand‑new transmission directly from Audi can easily reach 10,000 euros or more.
Fortunately, there are alternative repair options. Specialist companies overhaul mechatronic units at lower cost than dealers. These repairs often come with a warranty period of one to two years. If you have problems, always check first whether your vehicle is still under warranty or qualifies for a goodwill arrangement from Audi.
prevention through proper maintenance
The service life of your S tronic transmission depends heavily on maintenance and driving style. Regular transmission oil changes are the foundation of reliability. Use only Audi‑approved oil and follow the prescribed intervals. This prevents wear to the clutches and hydraulic components.
Adjust your driving style to protect the transmission. Avoid extremely aggressive acceleration from a standstill and, when changing gear manually, do not shift up and down unnecessarily quickly. On short trips, allow the transmission to warm up before accelerating hard. Cold oil lubricates less effectively and increases the risk of damage.
Schedule annual inspections at an authorised Audi workshop. Technicians can read out fault codes during these checks that have not yet led to symptoms. Early detection can make the difference between a simple software update and an expensive mechatronic repair. During major services, also have the transmission oil checked for metal particles, which indicate internal wear.
practical steps when warning lights appear
If you see the EPC light or PRND warning light come on, do not continue driving as if nothing is wrong. These signs indicate transmission problems that can worsen. Park the car safely and switch off the engine. Restart the engine to see whether the light goes out, but do not expect a permanent solution.
Call your dealer or a specialist workshop for advice. Describe the symptoms and ask whether it is safe to continue driving. In many cases you can still drive carefully to the workshop, but for serious faults it is wiser to have the car recovered. Continuing to drive with a failing transmission can lead to more extensive damage and higher repair costs.
Note down all relevant details for the mechanic. Which warning light was on exactly? Did you feel vibrations or jolts? Did reverse gear still work? This information speeds up the diagnosis and helps to find the right solution.
‘ Discover which other teething troubles this popular coupé has and how best to prevent or resolve them. ’
discover more about the Audi A5
On the Carnews website you will find extensive information about many more aspects of the Audi A5, from engine problems to maintenance tips and owners’ experiences. Discover which other teething troubles this popular coupé has and how best to prevent or resolve them.
frequently asked questions
The most common symptoms are warning lights on the dashboard (such as EPC and a flashing PRND indicator) and noticeably rough, jerky or delayed gear changes. Certain gears (for example reverse or higher gears) can also drop out, or the car can remain stuck in limp‑home mode with limited performance. In addition, problems often occur at low‑speed shift moments, such as harsh engagement or a “clunk” when pulling away or when selecting reverse.
Typical causes of S tronic problems on the Audi A5 are mainly failure of the mechatronic unit, overheating under heavy use (such as in traffic jams or when towing) and wear/oil that has not been changed for too long. These issues can be prevented by timely and regular replacement of the transmission oil according to Audi specifications and periodic checks at an authorised Audi workshop. In addition, keeping the software/firmware up to date and reading out fault codes at an early stage helps to detect emerging problems early. A gentle driving style, avoiding prolonged heavy‑load situations and preventing overheating all extend the life of the S tronic.
Possible repair options include: having the mechatronic unit overhauled or repaired, having the complete S tronic transmission overhauled, or – in severe cases – complete replacement of the transmission. A mechatronic overhaul generally costs between €1,000 and €2,000, depending on the specialist and parts. A full transmission overhaul is usually in the region of €2,500 to €4,000. Complete replacement with a new or factory‑reconditioned gearbox can run to around €5,000 to €7,000 including labour.
Yes, it can be sensible to buy a used Audi A5 with S tronic, provided you are extra critical about the condition of the gearbox. Pay particular attention to shift behaviour (jerks, gears dropping out, delayed response), warning lights (EPC, flashing PRND) and any fault codes in a diagnostic report. Check the service history carefully, especially whether the S tronic oil has been changed on time and whether any mechatronic repairs or updates have been carried out. Favour a well‑maintained example (preferably with a dealer history) and have the car inspected before purchase by a marque or transmission specialist.
The service life of an Audi A5 S tronic transmission can often be 200,000 km or more with normal use and good maintenance, but earlier B8 models are more prone to mechatronic and wear‑related issues. This lifespan can be optimised by changing the transmission oil on time and in line with the manufacturer’s schedule, and by having the gearbox inspected periodically by a specialist. In addition, gentle warm‑up, avoiding prolonged clutch slip (such as crawling in heavy traffic) and preventing overheating all significantly extend service life. Keeping the software up to date and having fault codes read out immediately when warnings appear also helps to limit damage at an early stage.