Audi A4 Multiple System Failure Linked to Clutch Switch

I had a very similar electrical fault on my 2018 Audi A5 2.0T last winter. Having some experience with modern car electronics, I first tried the basic troubleshooting but quickly realized this needed professional attention. The symptoms matched yours exactly, car stalling, cruise control issues, and transmission display problems. The clutch switch was indeed the root cause, but it wasnt the switch itself that failed. The workshop found a damaged wiring connection at the clutch pedal assembly where the cables had worn through over time. The repair involved replacing the wiring harness section and installing a new clutch switch connector. Total cost was 95 Euro including parts and labor. Since the fix, all systems have worked perfectly. Before suggesting specific solutions for your case, could you share: Any warning lights on the dashboard? Does the clutch pedal feel different than usual? When exactly did these issues start appearing? Have you had any recent work done on the car? This information would help determine if your A4 is experiencing the same faulty switch connection issue I encountered.

Last service was at 112000km, about 2 months ago. The car has been perfect until now. Actually, no warning lights appear on the dashboard when these issues occur. The clutch pedal feels completely normal with no change in resistance or travel. The problems started suddenly last week after parking overnight. No recent work has been done besides regular maintenance. Looking at the safety switch area as suggested, I noticed some wear marks near the gear selector where the wiring runs. Given our similar symptoms, especially the car stalling and gear display issues, the wiring harness connection seems like a logical starting point. The car starting problems are becoming more frequent, so I will schedule a workshop visit to have them specifically check the clutch pedal wiring and connections around the faulty switch area.

Thanks for providing those additional details about your A4. After hearing about the wear marks near the gear selector, I am even more convinced you are dealing with the same wiring harness issue I experienced. The sudden onset without warning lights is exactly how my electrical fault developed. The safety switch and associated wiring in these models are part of an interconnected system that affects multiple functions, which explains why the gear selector display, starting system, and cruise control all fail together. One quick check you can try: gently wiggle the wiring near the clutch pedal while someone tries to start the car. In my case, this would sometimes temporarily restore function, confirming the loose connection theory. Since your symptoms appeared after parking overnight, moisture could be aggravating an exposed wire section, similar to what caused my car starting problems. The lack of warning lights is typical because the system may not detect these intermittent wiring faults as permanent errors. Would strongly recommend having the workshop check the entire clutch pedal wiring harness, not just the switch itself. The repair should be similar to what I had done and relatively straightforward for them to diagnose with the right diagnostic tools.

Thanks for the detailed information about the wiring harness issue. The similarities with your case are really helpful. I just did the wire wiggle test you suggested and sure enough, the car started momentarily when moving the cables near the clutch pedal. This definitely points to an ignition problem related to worn wiring rather than just a faulty switch. I noticed the wear marks are actually worse than I initially thought when checking with a flashlight. The gear selector area shows clear signs of cable rubbing, which explains the intermittent electrical fault affecting multiple systems. Will book the workshop appointment for next week and specifically ask them to inspect the entire wiring harness around the clutch pedal assembly and gear selector area. The car starting issues are getting more frequent in damp weather, so this needs fixing soon. Really appreciate the detailed explanation about how these systems are interconnected. Helps a lot to understand why one wiring problem can cause so many different symptoms. Will update once the repair is done to confirm if it was indeed the same harness issue you experienced.