Possible Causes
WARNING: This page is about a different car, the 2005 Jeep Liberty. However, it is still accessible from the selected car via links, so may be relevant.
ENGINE SPEED SIGNAL CIRCUIT OPEN
ENGINE SPEED SIGNAL CIRCUIT SHORTED GROUND
ENGINE SPEED SIGNAL CIRCUIT SHORT TO VOLTAGE
TRANSMISSION CONTROL MODULE
ENGINE CONTROL MODULE
INTERMITTENT WIRING AND CONNECTORS