Rogue Oxygen Sensor Heater Failure

I had a similar issue with my Rogue! Check the wiring harness very carefully. Sometimes the insulation cracks or a wire gets chafed, causing an intermittent short. This can definitely trigger the oxygen sensor heater code and impact fuel economy. Which sensor is it, upstream or downstream? The upstream sensor is responsible for measuring the air-fuel ratio before the catalytic converter, and the downstream sensor monitors the converter's efficiency. If the heater element in the sensor fails, the sensor won't reach operating temperature quickly enough, and the ECU will throw a code.

Thanks for the tip! It's showing an error for the upstream sensor. How difficult was it to access the wiring harness in your case? I'm wondering if I should just take it to a shop.

Ah, upstream sensor, that's a critical one for air-fuel ratio. Accessing the harness can be a bit fiddly depending on your engine configuration, but it's generally not too bad. However, given the error code points specifically to the heater circuit and you've already checked the obvious connections, it might be time to consult a professional. If it’s indeed a defective cable or plug connection, as you suspect, it might be a simple fix, but diagnosing electrical issues can be tricky without the right tools. A workshop will also be able to test the sensor's heater element itself. I ended up taking mine in after struggling for an afternoon, it was worth it. Cost me about 95€.

Thanks for the advice, I appreciate it. I'll take it to a trusted workshop. Sounds like that's the best course of action, especially with the price you quoted. I will share the resolution once it's sorted.