VW Golf Multiple Sensor Failures: Wipers, Lights, Dash

I experienced almost identical issues with my 2015 VW Passat TDI. From my experience working on various car components, this sounds very familiar. The malfunctioning sensor symptoms you describe match exactly what happened in my case. The rain sensor and light sensor started acting up simultaneously, which initially made me think it was an electrical fault affecting multiple systems. Turned out the root cause was bubbles forming under the gel pad connecting the sensors to the windshield. This is a common issue with these sensor modules in VW models. Had it fixed at a workshop for 62€, they removed the old pad and installed a new one with proper adhesion. The repair solved all issues: Rain sensor working correctly again, Light sensor functioning normally, Speedometer dimming back to normal, Error codes cleared and never returned Before suggesting specific solutions, could you share: Any visible damage around the sensor area? When did these issues start appearing? Did it happen gradually or suddenly? Have you noticed any moisture or condensation near the sensor unit? This information would help determine if you are dealing with the same underlying problem I encountered.

Just had my latest service at 104936km. The sensor area looks perfectly clean with no visible damage. These issues started suddenly after heavy rain last week, all three problems appeared at once, which made me suspect a central electrical fault rather than individual sensor failures. No condensation visible around the sensor unit from what I can see. Checked all fuses as a first step but they are all intact. Good to hear about the gel pad solution, that does sound like it could explain the simultaneous failures. Will try to look more closely at the sensor mounting area when it stops raining. I am experiencing the exact same symptoms you described, unusual headlight activation and complete failure of auto wipers. Makes me hopeful it might be this relatively simple fix rather than a more complex electrical issue.

Thanks for the additional details about the timing and conditions. The sudden onset after heavy rain strongly reinforces my initial suspicion about the gel pad issue. This is exactly how mine started failing too, after a particularly wet period. The fact that all sensor functions failed simultaneously matches the gel pad failure pattern perfectly. When the pad loses proper contact with the windshield due to moisture intrusion or temperature changes, it typically affects all sensor functions at once. Looking at your mileage and comparing it to when my sensor fault occurred, these gel pads tend to start failing around the 100000km mark. The good news is that the repair is straightforward and relatively inexpensive compared to replacing the entire sensor unit. Quick tip while you wait for the repair: Try pressing firmly but carefully on the sensor housing against the windshield. If the functions temporarily return, this further confirms the gel pad theory since improving contact momentarily restores functionality. The clean sensor area and lack of visible damage also align with my experience, the issue is typically not visible from the outside since its between the sensor and glass. Given all these matching symptoms, I would recommend having the gel pad replaced rather than pursuing more complex electrical diagnostics first.

I really appreciate the comprehensive follow-up explanation. The pressing test suggestion is particularly helpful, I just tried it and noticed the auto wipers briefly worked when applying pressure, which seems to confirm your diagnosis about the gel pad. This makes complete sense given the timing after the heavy rain and that the gel pad tends to fail around my current mileage. The sensor calibration issues happening all at once was concerning, but knowing this is a known pattern with the gel pad failure is reassuring. I will schedule a workshop visit specifically mentioning the gel pad replacement rather than going through extensive electrical fault diagnosis first. The 62€ repair cost you mentioned is much more reasonable than what I was fearing might be needed for multiple sensor replacements. Will update once I get it checked, but feeling quite confident now that we have identified the likely cause. The sensor fault symptoms matching your experience so precisely, especially the unusual headlight activation and auto wiper failure, makes me optimistic this will resolve all the issues.