VW T-Cross Light Switch & Tail Light Malfunction Fix Needed

Had the same symptoms in my 2020 VW Polo TSI. The headlight switch malfunction started similarly with unusual tail light failures and inconsistent dashboard signals. The root cause turned out to be corroded wiring connectors behind the light switch module. Moisture had entered through a deteriorated seal and caused multiple connection failures. The electrical problem affected both the switch mechanism and signal transmission to the lighting control unit. Initial scanning showed various error codes, but they were all symptoms of the main connector issue. The repair required: Complete removal of the steering column cover, Replacement of the main light switch assembly, Installation of new wiring connectors, Resealing of the component housing This was a serious repair job requiring specialized diagnostic equipment. The issue would have caused complete lighting system failure if left unaddressed. After the fix, all lighting functions returned to normal and error codes cleared permanently. Important: The fuse box check often appears normal in these cases because its not a fuse-related problem, but rather a connection issue within the switch assembly itself.

Thanks for sharing your Polo experience. It sounds very similar to my T-Cross issue. The dimmer switch and tail lights started acting up in the same way. Did the corroded wiring problem cause any additional electrical issues after the repair? And would you mind sharing what the total repair cost was? I want to make sure I budget properly before heading to the shop, especially since the headlight switch assembly seems to need complete replacement. My mechanic mentioned the fuse box looked fine but I am now convinced its more about those connectors you described. Just trying to avoid getting overcharged for unnecessary diagnostic time.

Good news to report back, got my T-Cross repaired last week and the faulty light switch issue has been completely resolved. The dimmer switch and all lighting functions are now working perfectly. The mechanic confirmed it was indeed a damaged cable connection at the switch assembly, just as I suspected from our earlier discussion. No additional electrical problems have occurred since the repair. The final cost came to 95€, which covered the cable repair and connector replacement. This was much more reasonable than the initial diagnostic quotes I received. The dashboard lights and headlight switch are now responding consistently without any error codes showing up. For anyone facing similar issues: the fuse box checks often come up clear because these problems typically stem from failing switch connections rather than blown fuses. Getting straight to the wiring inspection saved both time and money.

Thank you all for the helpful advice. I finally got my T-Cross fixed yesterday and wanted to share my experience. Found a qualified mechanic who knew exactly what to check after I mentioned the corroded connector issue. The inspection revealed damaged wiring behind the light switch module, exactly as discussed. The repair took about 2 hours and cost 280€ total, including parts and labor. They replaced the main connector assembly and resealed the housing. All the tail lights and the dimmer switch now work flawlessly. The dashboard warning lights have disappeared and no more error codes show up during scanning. One tip: showing the mechanic the specific symptoms and suspected cause helped avoid unnecessary diagnostic fees. The fuse box was indeed fine, and focusing directly on the wiring saved both time and money. Really glad I asked here before accepting that first expensive quote. The car is running perfectly now with all electrical systems back to normal.