Oxygen sensor heater failure

O2 sensor heater fault, eh? Common enough. But before you start ripping things apart, are you sure it's actually the heater circuit? A bad sensor can sometimes throw a similar code. Have you checked the sensor's output voltage? A multimeter's your friend here. What kind of readings are you getting?

I haven't checked the voltage yet, just visually inspected the wiring. Where exactly should I be probing with the multimeter? Which pins on the connector?

Okay, visual inspections are good for spotting the obvious, but electricity's sneaky. Think of it like plumbing – you can see the pipes, but not what's happening inside. You need to see if the heater element is getting power. Find the heater circuit wires on the sensor connector – usually the same color. With the engine running, check for 12V across those pins. No voltage? Trace the wiring back. If you do have voltage, the sensor itself is likely toast. But honestly, for 95€, you're probably better off letting a shop diagnose it properly. They have the tools and experience to pinpoint the problem quickly and accurately.

Fair point. Sounds like chasing ghosts without the right gear. I dropped it off at the shop; they confirmed it was a faulty connection, just like I thought. 95€ later, all fixed. Thanks for the nudge.