what causes the air flow sensor to fail to function on 2003 Mercedes-Benz C240

after how many km are you suppossed to change the air flow sensor.

Asked by for the 2003 Mercedes-Benz C240
1 answer
try cleaning the sensor connections. 300, 000 kil. on my ride, and never had to replace it. of course your part could be just toast but try that first.