Tachometer

The CKP sensor is used as an input for tachometer information. The CKP sensor sends the ECM an A/C voltage signal. The ECM uses the A/C voltage signal to calculate RPM. The ECM sends an averaged tachometer message to the BCM via the CAN bus where the BCM sends a message to the I/P cluster over the Class II link. The ECM averages the tachometer information to ensure smooth tachometer fluctuations.