Mercedes CLK oxygen sensor heater failure

Oxygen sensor heater failure is common The heater helps the sensor reach operating temperature quickly for accurate readings A faulty sensor will trigger the check engine light and affect fuel economy Check the sensor's wiring and connector first Sensor testing requires a multimeter to check resistance and voltage If the wiring is ok, the sensor is likely faulty

Thanks for the quick reply I don't know much about sensor testing with a multimeter Can you explain the process What resistance and voltage values should I look for when testing the oxygen sensor Is there an easy way to check the exhaust system for leaks that could be causing this

Without the specific sensor data sheet, exact resistance values are hard to pinpoint Exhaust system leaks before the oxygen sensor can skew readings too Given your limited experience, it might be best to take it to a workshop The 95€ quote isn't too bad, especially if it includes the sensor

Thanks for the advice I took the car to a local workshop It turned out there was a faulty sensor The repair cost was exactly as quoted, 95€ The check engine light is now off, and my fuel consumption is back to normal Thanks again for your help