Tachometer: Description and Operation

TACHOMETER

The instrument panel cluster (IPC) displays the engine speed as determined by the engine control module (ECM)/powertrain control module (PCM). The IPC receives a class 2 message from the ECM/PCM indicating the engine speed. The IPC is capable of displaying between 0-7,000 RPM. The tachometer will default to 0 RPM if the ECM/PCM detects a malfunction in the engine speed sensor signal circuit.