FJCruiser NOx Sensor Faulty Connection

A NOx sensor failure on a 2022 FJCruiser is concerning, although a faulty connection is a plausible cause. Have you inspected the sensor's wiring harness and plug for any visible damage, corrosion, or loose connections? Also, are you experiencing any other symptoms besides the check engine light and exhaust leak, such as reduced engine performance or unusual fuel consumption? A leak in the exhaust system, even a small one, can affect the sensor's readings. It is important to rule out catalytic converter failure too.

I've checked the plug, looks fine. No other symptoms besides what I mentioned. Is there a way to test the sensor itself?

Testing the NOx sensor directly requires specialized equipment and knowledge, as it involves measuring the concentration of nitrogen oxides in the exhaust gas under various operating conditions. Given the potential for exhaust leaks to interfere with readings and the complexity of the system, I would advise having the system professionally diagnosed. Exhaust system integrity is paramount to pollution control. The error code stored in your car's memory will provide valuable information. Your issue will require specialized tools.

Thanks for the advice. Took it to the shop; faulty connection as suspected. Repair cost 95€.