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 (IC) module. The sensor wiring includes the following circuits:

The IC Module uses the sensors to determine the engine position and speed. A signal converter within the IC module, using the 18X CKP sensor 1, produces a digital 18X output signal to the powertrain control module (PCM) on the medium resolution engine speed signal circuit. The PCM monitors the low resolution engine speed signal circuit for errors.

Important: The PCM detects engine movement by sensing the airflow through the mass air flow (MAF) sensor is more than 3 g/s, or by sensing CMP sensor pulses.

DTC P0385 is a Type B DTC.

DTC P0385 is a Type B DTC.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Electronic Ignition (EI) System Description

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Attempt to start the engine. The engine should start and run.
2. Monitor the CKP Sensor A and the CKP Sensor B parameters. The parameters should increment from 0 to 255 continuously with the engine running or cranking.
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

1. Ignition OFF, disconnect the IC module connector. Test for less than 3 ohms between the IC module ground circuit IC module terminal K and battery ground

⇒	If greater than the specified value, test the ground circuit for an open/high resistance.

2. Ignition ON, test for B+ between the IC module ignition voltage circuit IC module terminal P and ground.

⇒	If less than the specified range, test the IC module ignition voltage circuit for an open/high resistance or short to ground.

3. Disconnect the CKP sensor connector.
4. Test for less than 1 ohm on the low reference circuit CKP sensor 2 terminal C and the IC module terminal M.

⇒	If greater than the specified value, test the low reference circuit for an open/high resistance.

5. Connect the IC module.
6. Ignition ON, test for more than 10 volts between the 12-volt reference circuit CKP sensor terminal D and ground.

⇒	If less than the specified range, test the 12-volt reference circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the IC module.

7. Ignition ON, test for 4-8 volts between the signal circuit CKP sensor 2 terminal A and ground.

⇒	If less than the specified range, test the signal circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the IC Module.

⇒	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the IC Module.

8. Ignition ON, using a jumper wire connected to ground, momentarily touch the CKP sensor 2 signal circuit CKP sensor terminal A repeatedly. The CKP Sensor parameter should increment.

⇒	If the CKP Sensor B parameter increments, replace the CKP sensor.

9. Ignition OFF, disconnect the IC module connector. Ignition ON, using a jumper wire connected to B+, momentarily touch the low resolution engine speed signal circuit IC module terminal D repeatedly. The CKP Sensor parameter should increment.

⇒	If the CKP Sensor B parameter increments, replace the IC module.

⇒	If the CKP Sensor B parameter does not increment, test the low resolution engine speed signal for an open/high resistance, short to ground, or a short to voltage. If all circuits test OK, replace the PCM.

1. Inspect the CKP sensor for looseness and correct installation.
2. Connect jumper wires from the CKP sensor connector 12-volt reference CKP sensor terminal D and the low reference CKP sensor terminal C to the CKP sensor; turn ON the ignition, with the engine OFF.
3. Connect a DMM to the CKP sensor signal CKP sensor 2 terminal A at the CKP sensor and observe the Duty Cycle. Pass a steel object by the sensor repeatedly. The Duty Cycle should increment.

⇒	If the Duty Cycle does not increment, replace the CKP sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.