Operation CHARM: Car repair manuals for everyone.

Tachometer

The tachometer is an analog gauge that is located in the Instrument Panel Cluster (IPC). The tachometer is operated by the IPC with software control. The VCM/PCM sends Tach pulses to the IPC on a discrete circuit at the rate of 2 pulses per engine revolution with the engine running. The IPC will interpret the tach pulses in order to appropriately display the engine RPM on the tachometer.