The Jeep Grand Cherokee crank sensor is a sensor that determines the position and rotational speed of the crankshaft, which is vital information for the onboard computer to know when to time ignition and fuel injection. The crank sensor is one of many sensors that work together to ensure that the vehicle's engine is running properly and efficiently.
A Jeep Grand Cherokee crank sensor is located underneath the front side of the engine, and it works very similarly to the crank sensors on all modern vehicles. The sensor utilizes magnetism to determine patterns in the crank shaft. When teeth from the shaft pass through the magnetic field created by the crank sensor, it produces a series of on and off switches within the sensor that determine the position and speed of the crankshaft.
If the crank sensor within a Jeep Grand Cherokee is malfunctioning, the vehicle's check engine light will blink on the dash. Replacing the crank sensor is very easy as long as the person who is replacing it has basic knowledge of the engine's wiring. The sensor must simply be unscrewed from the engine and disconnected from the onboard computer. New sensors can be bought through the Jeep website, and should be placed exactly where the old sensor was located. The sensor will come with a clip at the end of a wire that will connect back to the onboard computer.