Instrument Cluster (IC): Gauges: Tachometer
WARNING: This page is about a different car, the 2007 Lincoln Mark LT and 2007 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.
The electrically operated tachometer indicates engine speed in revolutions per minute (rpm). The tachometer range is 0 to 7,000 rpm. The tachometer receives the signal through the communication network from the PCM. If the rpm information sent to the instrument cluster is invalid or missing, the instrument cluster defaults the tachometer to 0 rpm.