Circuit Description

The crankshaft position (CKP) sensor contains 2 hall-effect switches in one housing. This sensor configuration produces 2 separate CKP sensor pulses. These pulses occur when 2 interrupter rings, mounted to the crankshaft balancer, the outer one containing 18 evenly spaced windows and blades, the inner one containing 3 unevenly spaced windows and blades, pass by the sensors. The 18X sensor produces 18 pulses per engine revolution. The 3X sync sensor produces 3 pulses per engine revolution, each pulse representing a pair of companion cylinders. Both sensors are connected directly to the ignition control module (ICM). The sensor wiring includes the following circuits:

• The CKP sensor 1 signal circuit
• The CKP sensor 2 signal circuit
• A shared 12-volt reference circuit
• A shared low reference circuit

The ICM uses the sensors to determine the engine position and speed. A signal converter within the ICM, using the CKP sensor 1 18X pulse, produces a digital 3X output signal to the powertrain control module (PCM) on the low resolution engine speed signal circuit. The PCM monitors the low resolution engine speed signal circuit for errors. If the PCM does not receive a signal from the ICM, DTC P0385 sets.