Scenic oxygen sensor heater fault

I had a similar problem with my old Opel Astra, but a different sensor was the culprit. The malfunction indicator was glowing. Have you checked the cable and plug connection to the sensor? That was my issue. Could be corrosion or damage there.

Thanks for the tip! When you say 'cable and plug', are you talking about the wiring harness leading to the O2 sensor? Was it obvious when you found the problem, or did you need special tools to diagnose it?

Yep, the wiring harness. I could see some green corrosion on the plug itself. I tried cleaning it, but it didn't help. Ended up needing a new connector and some wiring repair. Honestly, if you're not comfortable messing with wires, I'd suggest taking it to a workshop. Save yourself the hassle. The repair ended up costing me around 80€ back then.

Thanks a lot! I appreciate the advice about the workshop. I checked the connection, and you were spot on – it's corroded. I'm not confident enough to fix the wiring myself, so I'm booking it in. Got a quote for 95€, which seems reasonable. Hopefully, that will solve the issue!