Audi Q5 adaptive cruise problems

Filed Sep 12, 2026 · Brakes, Driver assistance · VA

Brake Electronics Control Unit Failure (DTC U041800): Logged active diagnostic code U041800 (implausible signal in address 812C). Dealership records confirm no permanent remedy exists, with software patches delayed into Q3 2026, leaving active braking and electronic system faults unaddressed. Electrical Grid Collapse & Parasitic Battery Drain: Vehicle experienced exterior lights activating independently during sleep mode and cyclical 300mA to 2.0A parasitic draws. Required warranty replacement of the Central Electrical Control Module (J519), Low Voltage Power Distributor Module (J1282), and primary 12V battery (RO #AUCS214055). Powertrain & Transmission Engagement Failures: Experienced Check Engine Light cycling and a total failure to engage "Park" for 20 minutes. Scanned hard factory codes P187C00 (gear actuator 3 failure), P086900, and P270800, requiring ten consecutive distance sensor calibrations. Adaptive Cruise Control & Restraints Malfunctions: ACC fails to engage due to false occupant-detection logic errors, triggering phantom rear-seat belt warnings while driving solo and throwing error messages that compromise restraint safety architecture. Liftgate Architectural Failures: Rear trunk lid fails to open or latch fully due to software conflicts with the mobile key platform, causing the control unit to lose its calibrated position.

Filed Aug 16, 2026 · Driver assistance · FL

The vehicle has experienced intermittent failures of multiple advanced driver-assistance systems beginning at approximately 150 miles. Warning messages have included Adaptive Cruise Control Not Available, Distance Warning Not Available, and Pre-Sense Malfunction. These failures disable or make unavailable systems intended to maintain following distance and warn or intervene for potential forward collisions. The warnings have occurred while the vehicle was being driven and create uncertainty about whether the safety systems will function when needed. An authorized Audi dealer first verified driver-assistance concerns during an April-May 2026 repair visit, found multiple stored faults, opened a technical assistance case, and documented active/static faults involving the front driver-assistance camera and related control modules. The problems recurred. On August 10, 2026, at approximately 1,670 miles, the authorized dealer duplicated the Distance Warning illumination and ACC unavailable condition, searched for service bulletins, opened another technical assistance case, performed a capacitor discharge, and ran replacement test plans for the A5 and 0075 control modules. Video of the warnings was provided to the dealer. No crash, fire, or injury has occurred. The vehicle and repair records are available for inspection.

Filed Aug 2, 2026 · Electrical · ME

While driving my 2026 Audi Q5, the instrument cluster display went completely black twice while the vehicle was in motion, eliminating my speedometer and all warning indicators. Separately, during another drive, the vehicle displayed "Suspension: malfunction! Safely stop vehicle" on two occasions within minutes of each other, at approximately 15 mph and 17 mph, each accompanied by illuminated ABS and BRAKE warning lights. Immediately after, the odometer failed, displaying dashes instead of mileage, and the display spontaneously switched from miles to kilometers. This was followed by approximately 15 additional system warnings disabling adaptive cruise assist, lane departure warning, exit warning, active front assist/distance warning, parking systems, fatigue warning, traffic sign recognition, distraction warning, rear cross-traffic assist, and emergency assist. The vehicle was taken to an authorized Audi dealer for diagnosis. The technician was unable to duplicate or identify the cause of the failure. I have photographic documentation, with timestamps, of every warning message described above. This appears to be an intermittent failure of a central vehicle module or communication bus affecting braking, stability, and driver-assist systems simultaneously, creating a safety risk while driving.

Filed Jul 31, 2026 · Brakes, Driver assistance · NY

On XXX at approximately 5:00 PM, my 2025 Audi Q5 (VIN: [XXX]) initiated an unprovoked forward collision warning and emergency braking intervention while I was traveling at approximately 57–58 mph on [XXX]. Road conditions were clear and dry. Weather was sunny. Adaptive Cruise Control was not activated. I was the sole occupant of the vehicle. A vehicle was making a lawful turn onto the roadway from a T-intersection. There was substantial distance between my vehicle and the turning vehicle. No collision risk existed and no evasive action was required. Despite this, the vehicle's forward collision system overrode my control and initiated emergency braking without cause. As a result of the sudden braking and the force of the seatbelt restraint during the event, I sustained abdominal pain and lower back pain that began immediately following the incident and persisted thereafter. This incident did not occur in isolation. Prior to this event, the vehicle had already exhibited a documented pattern of electronic and driver assistance system malfunctions, including intermittent check engine warnings, repeated false-positive driver assistance alerts, power liftgate malfunctions, sunroof malfunctions, and additional electronic irregularities. All of these concerns were reported to Audi Albany prior to the emergency braking event. Following a service visit, I was told nothing further could be done. The vehicle is currently at Audi Albany undergoing inspection at the request of Audi of America, including a review of the Event Data Recorder. I am filing this complaint to ensure the incident is part of the federal safety record. A driver assistance system that initiates emergency braking at highway speed without a valid hazard present, on a vehicle with a prior history of false-positive alerts, represents a safety defect that I believe warrants federal documentation and review. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Jul 29, 2026 · Driver assistance, Electrical · TX

I bought this car in 12/2025. After putting approximately 60 miles on the car, the onboard computer would not save the inputted data. Took back to dealership and update performed. Upon returning the car for this work, the adaptive cruise control would shut itself off on the way to the dealer. They could not replicate this issue. Since having the car for about 6 months the car has been in to the dealer approximately 7 times all for different warning lights including having the module needing to be replaced that controlled the A/C. The most recent problem is the vehicle locking up its brakes and rapidly fastening down on the seatbelt while driving stating a red danger message that flashes on the informatic screen and then disappears but will not show up on the MMI screen. This has happened twice in the last 10 days. Upon the first visit I was told that Audi has been having a lot of problems with the 2025 Q5 because of the computer. The car is currently back in the shop for continued safety components selectively turning off on their own and the car slamming on its brakes when there is no adverse event. There is supposed to be a patch coming out in Quarter 3 2026, but an actual update isn't set until 04/2027 per Audi service. I have stressed how not having these functions working correctly has made the car a hazard to drive as I never know when it will act appropriately. Also the lane departure feature does not always work appropriately and will try to hold in a improper travel and will jerk the wheel. I have completely turned that function off since it has tried to turn me into on coming traffic.

Filed Jul 3, 2026 · Driver assistance · WA

I had adaptive cruise control on in moderately flowing traffic on the highway. Without warning the adaptive cruise control on it's own turned off/disengaged and slammed on the brakes. I had not changed lanes nor had anyone moved in front of me. The weather was clear. My safety and the safety of those behind me was put at risk. I've taken the vehicle to the dealer and they have not been able to reproduce the issue yet. They inspected the vehicle and took it for an initial 7 mile test drive, said they didn't find any problems and tried to return the car. There were no warning lamps or messages before or after the incident. I didn't notice any when it happened as I was focused on trying to avoid an accident. Prior to the incident the adaptive cruise control has turned off multiple times with the message " Adaptive cruise assist: currently not available" for no apparent reason, but this is the first time hard breaking was applied.

Filed Jun 26, 2026 · Driver assistance, Electrical · IN

The 2025 Audi Q5 has a systemic problem with its Multi Meidia and driver assist features, such as cruise control, side mirrors, back up camera, directional maps, etc, which malfunction at inopportune times causing major distraction while driving. Audi has been aware of the problem since 2025 and had a partial patch available in 2025, but did not inform drivers nor make it available unless requested by vehicle owner. Dealers, such at the dealer we purchased our Audi Q5 from, D-Patrick, Evansville IN, did not make us aware of flaws, and kept inidicating that it was or phones or other situations which could be easily adjusted, which was false. We did not feel safe using the vehicle and conatantly look for alternatives, due to fear and safety concerns. The first incident occured immediately after pruchase of the vehicle and has continued on a repeat basis. There are numerous reviews on line with 2025 Q5 owners reporting safety concerns while operating these vehicles.

Filed Jun 11, 2026 · Driver assistance · IL

I was driving down a regular road by my house, full sunshine, perfect road, nothing unusual. In fact, it was such a nice day, the sunroof was open and windows were down. My dog was in the back seat after just being picked up from grooming happily enjoying the day with his head out the window. I was on a road with the speed limit of 30. I was going 30 mph. Nothing unusual. Literally, out of nowhere, like my car was possessed, is the best way I put it, my car abruptly braked in an attempt to stop on a dime. My car screeched to a stop while simultaneously my windows rolled up, my sunroof closed and my seat belt tightened, locking me in place. My dog was thrown forward. It was terrifying! Luckily, no one was behind me or they would have certainly rear-ended me. Nothing was in the road. Absolutely nothing. It happened so quickly in a split second. I put my hazards on and finished the next 2 miles home. I called Audi for a service appointment. I took my car in, again going down back roads with my hazards on. Audi charged me $400 to run a diagnostic report and shows there is a fault code J428. This fault code I researched is for the front/right ACC radar sensor that powers Adaptative Cruise control and Pre-Sense braking system. The fault code erroneously detected an obstacle and did abrupt braking. Audi told me that they would charge me $4,000 to fix it. I contested that as a safety issue it should be fixed as there is also Audi TSB2063502 referencing problems. This is a major safety issue as if I was going 70 MPH, I could cause a massive accident where I could be killed, anyone in my car, as well as others behind me in a massive car pile up. I feel ethically, this must be a safety recall to replace this fault in all vehicles. I am also requesting payment to fix from Audi. As an attorney (#[XXX]), Audi is under notice that they have a major safety defect on their hands and should take steps to protect drivers safety. Thank you. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed May 21, 2026 · Acceleration, Driver assistance · MA

Adaptive cruise control not working....,Intermitently shutting off. This is coinciding with numerous engine, oil and gas warning lights going off in the Audi MMI system. Lead tech at Audi dealership in Norwell MA is telling me that this is a well known issue with the 2025 Audi Q5 needing a software update that will not be available until sometime in the 3rd quarter

Filed May 20, 2026 · Driver assistance · IL

Regarding the adaptive cruise control, sometimes the system won't engage. The first time this happened a warning popped on the screen saying something about seatbelts. I've learned that the problem can be "fixed" by pulling off the road and turning the car completely off. That includes opening a door to silence the radio. The cruise has always worked afterwards. Sometimes while driving on cruise control, in a straight line, the car brakes abruptly for no apparent reason. Granted we were on the interstate and there was traffic but no reason whatsoever to brake. The cruise control is easily confused on roads with multiple lanes and sharp curves, like on [XXX] between Asheville, NC and Knoxville, TN. The car will brake abruptly, seemingly sensing a car in front of me but in a different lane. Sometimes when reengaging cruise control the speed goes not to the speed I had set but what it "sees" as the posted speed limit. This caused the car to speed up in a construction zone and slow to a speed below the prevailing speed of traffic around us. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)