VW Taigo Multiple Sensor Failures, Rain Unit Issues

As an owner of a 2020 VW T-Cross with some repair experience, I encountered an identical malfunctioning sensor issue. The symptoms matched yours exactly, unusual headlight activation, rain sensor failure, and auto-dimming problems. The root cause was air bubbles forming under the gel pad connecting the light sensor to the windshield. This created false readings and confused multiple sensor systems. Had it fixed at a workshop where they removed the old sensor pad, thoroughly cleaned the area, and installed a new one with proper adhesion. Total cost was 62€ for parts and labor. The repair resolved all sensor fault indicators and restored normal operation of all affected systems. Most importantly, no additional calibration was needed after the fix. To help diagnose your case more accurately, could you share: Whether the issues started gradually or suddenly, If you recently had any windshield work done, Whether the sensor errors show consistently or intermittently, The exact error codes from your diagnostic scan This type of car components issue is fairly common in VAG vehicles from that generation, but proper diagnosis is crucial since similar symptoms can have different causes.

Thanks for the detailed reply. My issues started suddenly after heavy rainfall last week. No recent windshield work done. Service history is clean with last maintenance at 10000km. Error code P0603 appears consistently in the diagnostics. The rain sensor and auto sensor problems are becoming more frequent. Just yesterday, the headlights activated three times while parked in broad daylight. Light sensor malfunction seems to worsen in humid conditions. Will get the gel pad checked based on your experience. Did you notice any specific weather-related patterns before your repair?

Thanks for the additional details. The error code P0603 combined with weather sensitivity actually points to a different issue than what I initially experienced. In my case, the gel pad was the culprit, but your symptoms suggest possible water ingress affecting the main sensor control module. After dealing with similar car electronics issues, I learned that P0603 specifically indicates a Keep Memory error in the sensor control unit. The correlation with humid conditions is significant. On my T-Cross, we eventually discovered water seepage through a damaged seal around the sensor housing, which caused intermittent shorts in the control module. The repair involved: Replacing the complete sensor unit (320€), Installing new weather seals, Basic sensor calibration post-repair This solved both the rain sensor malfunction and unusual headlight activation. Unlike the gel pad issue, this repair did require professional recalibration of the auto sensor systems. Given your error code and weather correlation, I suggest having the seals and sensor housing checked before replacing just the gel pad. Water damage to sensor electronics can worsen quickly if not addressed. Would you mind checking if there are any visible water marks or condensation around the sensor housing near your rearview mirror mount? This could confirm whether you have the same water ingress problem I encountered.

Thanks for the input regarding water ingress and sensor module issues. I just checked the rearview mirror area and found moisture traces around the sensor housing, exactly where you mentioned. This definitely aligns with your diagnosis of water seepage being the root cause. Given the consistent P0603 error and the visible water marks, I will schedule a repair focused on the control module and seals rather than just the gel pad. The weather correlation makes perfect sense now, especially since the light sensor problems intensify during humid conditions. The quoted repair cost at my regular shop is 295€ for the complete sensor unit plus labor, slightly better than what you paid. They confirmed sensor calibration will be included in the service. Planning to get it done next week before any potential water damage spreads to other car electronics. Thanks for helping narrow down the actual problem. This saved me from pursuing the wrong repair path with just the gel pad replacement.