Which parts fail
Components named in complaints (automatic emergency braking, adaptive cruise, lane keeping, backup camera).
Owner reports
Selected complaints filed with NHTSA by 2020 Audi A4 owners, lightly cleaned up (personal details are redacted by NHTSA).
Starting in around February the MMI (central computer system) system started rebooting at random times while the car was started. At first, I thought there must be something wrong with just my car. I took it into the dealer, and they said there was nothing they could do about it. I did some research and found many other people are having the same issues (thread has over 550 posts linked at the bottom) with the year model and they all started at the same time. I reached out to Audi International, and they say they've never heard of the issue, it's not widespread and to take it to the dealer (which is clearly a lie given the linked thread), when I took it to the dealer, they said Audi international needs to provide and update. …
The MMI (infotainment) system in my 2020 Audi A4 start to have intermittent reboot issue during normal driving starting earlier this year. It was working expected without reboot until that time. The MMI system reboot creates harzards and danger for drivers because during rebooting, the whole navigation system is not working neither did Carplay. What's even worse is that the back up camera and radar will also be disabled during rebooting. The rebooting time varies from 10s of seconds to minutes, with black screen and/or laggy, frozen screen. After rebooting, the system will have error prompt such as 'The selected user has not been used for a extended period of time' but the selected user has been using the vehicle all the time. …
The MMI spontaneously reboots numerous times while driving. When the reboots happen, the screen goes black and key systems such as the backup camera, rear obstacle detection, and navigation, become unavailable until the reboot completes and the systems reload. Restoring functionality requires user input to get through the loading screens. The issue started in February 2025. There are numerous TSBs (filed with NHTSA) that point to available software updates that should be applied to address infotainment-related issues. This appears to be a widespread issue based on the numerous reports found on user forums online, affecting the same model year vehicles (for multiple examples, refer to [redacted] ). …
Vehicles MMI constantly cycling through reboot - inordinate amount of previous complaints about this exact issue - Dealer advised a min $1040 ($370 to diagnose + $670 new MMI) to diagnose and change MMI console with NO guarantee it will work and that's because: the dealer has not updated MIB2 (aka the MMI) using the instructions on a different bulletin, titled "TSB 2067021 - 91 MIB3: Garage opener/SXM/Online Radio or other malfunctions B129B11, B129C22, B123B13, B123C13, U044700 or B200000" (latest version is from July 27, 2024, they've had 6 revisions), before applying the most recent update. So it looks like, at a minimum, I'm two updates behind (encompassing of course, a ton of intermediate versions). So right there, the dealerships have been failing by not even taking the time to read Audi's own TSBs. …
I have started experiencing issues with the MMI (infotainment system) system rebooting every few minutes. It was very sporadic at first, but now it is at the point where I frequently don't have time to get into the system before it starts the reboot cycle again. When this happens, the screen will go blank for several seconds. Then a message will show for several seconds saying that the system is loading. The system will then try to guide me through several prompts to try to log back into the car's MMI system. Even if I choose "Guest User" I am shown multiple prompts before I get into the system and can use the functions located in the MMI. This can and does happen while driving, while parked, and while backing up. This reboot sequence makes all of the safety features, including collision avoidance and the backup camera inaccessible during this time. …
The MMI system in the car spontaneously reboots, every 2-5 minutes. During reboot, the screen goes black and systems such as the backup camera, rear cross traffic detection, rear collision warning, and navigation are lost until the reboot completes and the user has to cycle thru multiple input & loading screens to get back to full functionality. Given the length of time the reboot requires, often the screen gets back to usability, only to reboot again less than a minute later. The reboots are random and occur whether the radio is off, radio playing; bluetooth connected, not connected; android auto running/not running; car moving, car parked; engine off, engine on; cold weather/hot weather; wet weather/dry weather. …
2020 Audi A4 went in for service on 2/27. After servicing, car's electrical MMI system started rebooting randomly while driving. When this random reboot occurs, the backup camera, parking collision warning no longer function. On some trips, this occurs as often as 5-6 times while others occur just once. The problem is increasing in frequency. I took it back to the dealer on 4/16 where the only thing they could find via codes was a faulty a/c component. After searching online for a solution, I arrived at several reddit threads with other 2020 audi a4 drivers experiencing similar issues at the end of February. The thread is listed below. [redacted] As mentioned earlier, this lack of system functioning is unsafe as advanced driving features of the car will not work when in a reboot mode. …
Audi mmi will shut off randomly, while in drive(accelerating or not), reverse, or idle, causing the camera and sensors to become inoperable, and the vehicle gives a warning saying "parking aid: malfunction! Obstacles cannot be detected" only after the mmi system has rebooted. When this occurs while reversing, not only a car but a pedestrian may be passing behind me and I would not know. This issue also causes the car to randomly ask for a pin to log in to the mmi after rebooting randomly (there is no pin that exists for any users in my vehicle and even asks when i am on a guest user), creating further distractions while driving like when i may need to use navigation, especially when the system reboots repeatedly five to six times within a ten minute time frame. This issue has been recurrent from 3/13/2025 to present 7/13/2025
While driving, the infotainment screen (MMI system) randomly reboots without warning. This happens frequently, often multiple times during a single trip. When it restarts, the screen goes black and temporarily disables important functions like the navigation, rear-view camera, audio, and vehicle settings. This poses a safety risk by distracting the driver and making it difficult to safely reverse or park. I brought the vehicle to the dealership, and they confirmed the only solution is to replace the MMI system. However, I've seen many other Audi A4 owners online report the exact same issue. Given how widespread this appears to be, I believe this should be addressed as a manufacturer defect rather than a repair cost placed on the owner. There were no warning lights or messages before the screen began to fail.
The vehicles MMI system out of nowhere keeps turning off and says "checking for remote access rights" and this happens constantly now for the past few months. Happened to reboot when I was backing out of a parking spot and my rear view camera turned off as well as the parking collision monitoring system. They all stopped working and I almost hit a pedestrian walking behind my car. This is a serious safety concern as this keeps happening every few minutes now in my car. Not sure if it became more persistent since my last vehicle maintenance few months ago but it's a problem. Driving with navigation engaged, it happened again while on highway and system shut down and I had no clue where to go. It's very distracting to happen while driving and all shut down.
Collision Avoidance complaints in other A4 years
Frequently asked questions
How common are collision avoidance problems on the 2020 Audi A4?
NHTSA has 49 complaints about the driver assistance of the 2020 Audi A4, 38% of the model year's 128 complaints. The component named most often is warnings (42 mentions).
Is there a recall for 2020 Audi A4 collision avoidance problems?
No. NHTSA lists no driver assistance recall for the 2020 Audi A4, though it has 3 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.