Ccrosser Oxygen Sensor Heater Failure

That sounds familiar. I had a similar problem with my old Opel Astra, although it was a gasoline engine. The check engine light was on, and the error code also pointed to the oxygen sensor heater. I checked the sensor itself, but the issue was intermittent. The resistance values were all over the place when testing the heater element. Have you checked the sensor's resistance? It might be difficult, but it's worth a try.

So, the resistance values were jumping around? I haven't used a multimeter yet, hoping it was a loose connection. When you say 'all over the place,' are we talking open circuit, or just fluctuating wildly? Did you solve the issue, or replace the sensor?

It was fluctuating wildly, not a clear open circuit. I fiddled with the connector, cleaned it, and tried to reseat the pins, but no luck. Eventually, I took it to a workshop. They confirmed it was the sensor itself. Sometimes it's not worth trying to fix it yourself, especially with emissions-related stuff. I suggest you go to the workshop and let them check it.

Okay, I appreciate the insight. I'll book it in with a local garage. They quoted around 95€ for a new sensor and fitting, which seems reasonable. Thanks for sharing your experience!