Tachometer: Description and Operation

TACHOMETER - PCM OUTPUT
The PCM sends engine speed information on the CCD Bus to the Body Control Module for tachometer operation. The PCM calculates engine RPM from the crankshaft position sensor input.

CIRCUIT OPERATION
The tachometer receives its information across the CCD Bus from the Body Control Module (BCM). Information on engine RPM is transmitted from the Powertrain Control Module (PCM) across the CCD Bus to the BCM. The BCM calculates the position of the tachometer pointer based on the input from the PCM and adjusts the position of the gauge pointer to the necessary position. This signal is sent over the CCD Bus to the instrument cluster.