Volvo C30 oxygen sensor heater fault

Greetings. I own a Volvo C30 as well, though not the same build year. I encountered a similar issue some time ago. The symptoms you describe align with a failing oxygen sensor heater element. One should begin by meticulously examining the sensor's wiring and connector for any signs of corrosion, damage, or loose connections. Have you performed any sensor testing with a multimeter to ascertain the heater element's resistance?

Thanks for the reply! No, I haven't tested the sensor with a multimeter yet. Could you elaborate on how to do that, or where I might find some instructions?

While I could provide instructions on sensor testing, it is a delicate procedure best left to experienced technicians. Given the symptoms and your initial assessment, the probability of a defective cable or plug connection is high. My considered recommendation would be to present the vehicle to a qualified workshop for comprehensive diagnosis and rectification. It is probable that a faulty sensor is the origin of your malfunction indicator.

Understood, I appreciate the advice. I took it to a workshop, and you were right, it was a faulty connection to the oxygen sensor. Repair cost was 95€ Thanks again!