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Tachometer: Description and Operation

TACHOMETER
The IPC displays the engine speed in response to the information received from the PCM. The PCM converts the data received from the engine into a 2 pulses per engine revolution signal. The IPC uses the engine speed signal circuit from the PCM in order to calculate the engine speed. The tachometer defaults to 0 RPM if a malfunction in the engine speed signal circuit exists.