Audi Q2 Multiple System Failures Point to Electrical Fault

As someone with some experience working on Audis, I had a very similar issue with my 2015 Audi Q3 2.0 TFSI. The symptoms you describe match exactly what I encountered, unusual system failures and warning signals popping up on the dashboard. After multiple OBD-II scans showing inconsistent error codes, I took it to my regular workshop. The diagnostic revealed the root cause was a faulty cable connection to the control module, specifically where it connects to the vehicle's BUS system. This explained why multiple systems were affected simultaneously. The service required included: Complete diagnostic scan, Removal of the control module, Repair of the cable connections, System reset and testing Total repair cost was 155 Euro, including labor and parts. The unusual system failures stopped completely after this fix. Before I can provide more specific advice for your case, could you share: Current mileage on your Q2, When did these issues first appear, Which specific error codes are showing up, Have you had any recent work done on the electrical system This information would help determine if your issue is identical to what I experienced with my Q3.

Latest service was at 171500 KM and now getting the same issues again. The check engine light started appearing more frequently since then. The warning light pattern seems to match what you described, particularly the unusual system failures affecting multiple components. My fault codes are mostly related to communication errors between modules (U0100, U0101) which seems to align with your diagnosis of a cable connection problem. Did your repair shop mention anything about water damage or corrosion being a potential cause? Asking because the service required notification started appearing more often during rainy weather. The 155 Euro repair cost seems reasonable given the scope of work needed. Going to schedule an appointment to have this checked out, since these system failures are becoming more frequent.

Thanks for providing those additional details about your Audi Q2. The increased frequency of warning signals during wet weather definitely reinforces my initial suspicion about the cable connection issue. In my Q3, the workshop actually found slight corrosion at the connection points, likely due to moisture penetration over time. The U0100 and U0101 communication error codes you mentioned are exactly what my OBD-II scan showed before the repair. These codes typically indicate problems with the CAN bus communication, which matches the cable connection diagnosis. After my initial repair, I had a similar situation where the system failure messages returned at around 165000 KM. The workshop discovered that while the main connection had been fixed, moisture had affected a secondary connector. The follow-up repair involved: Additional waterproofing of all control module connections, Application of dielectric grease, Installation of protective covering This second repair cost 180 Euro but completely resolved the recurring issues. Given your mileage and similar symptoms, especially the correlation with wet weather, I would recommend mentioning these specific points to your workshop. The service required light should stop appearing out of nowhere once all connection points are properly sealed and protected. Consider requesting extra moisture protection measures during the repair to prevent future issues.

Thanks for sharing those repair details. Your explanation about the corrosion at connection points makes sense, especially since my malfunction indicator acts up more during wet conditions. The check engine and warning light patterns do seem to point toward moisture-related electrical issues. Just booked a workshop appointment for next week. I made sure to mention the control module connection problems you experienced and the specific error codes showing up in my engine diagnostics. They confirmed they can do a full system check and cable inspection for around the same cost range you mentioned. Will definitely ask them to check for moisture damage and apply that extra waterproofing treatment you suggested. Hoping this resolves all these unusual system failures and error messages. The recurring service required notifications have been really frustrating to deal with. I will update this thread once I get the repair done in case others run into similar issues with their Q2. Really appreciate the detailed explanation of your experience, it helped narrow down what to look for.