This cylinder head temperature sensor monitors coolant temperature at the cylinder head and sends a signal to the engine control unit. The ECU uses this signal to adjust fuel delivery, injection timing, and cooling-fan engagement. A failed sensor can cause incorrect fuel metering, rough running, or a no-start condition. The sensor is manufactured by AGCO to match the original thermal-response curve, ensuring the ECU receives the same resistance values as the factory component. On installation, clean the sealing surface and apply thread sealant if the sensor uses a tapered thread.