Diagnostic Instructions

DTC Descriptor

DTC P0335: Crankshaft Position (CKP) Sensor Circuit

DTC P0335 28: Crankshaft Position (CKP) Sensor Circuit Incorrect Frequency

DTC P0335 29: Crankshaft Position (CKP) Sensor Circuit Too Few Pulses

DTC P0336: Crankshaft Position (CKP) Sensor Circuit Performance

Circuit/System Description

The crankshaft position (CKP) sensor is located on the left rear of the engine block. The CKP sensor produces an AC voltage of different amplitude and frequency depending on the velocity of the crankshaft. The CKP sensor works in conjunction with a 58X reluctor wheel that is attached to the crankshaft. Each tooth on the reluctor wheel are spaced 6 degrees apart with one span having a 12 degree space. The engine control module (ECM) uses the 12 degree space to determine top dead center (TDC) for cylinders 1 and 4. The ECM determines when cylinder 1 is on the compression stroke by monitoring the CKP sensor and the camshaft position (CMP) sensors. The ECM can synchronize the ignition timing and fuel injector timing based on the CKP sensor and the CMP sensor inputs.

Conditions for Running the DTC

Conditions for Setting the DTC

P0335, P0335 29

The ECM does not detect a signal from the CKP sensor. OR, the ECM detects a CKP signal without reference pulse.

P0335 28, P0336

The ECM re-syncs the engine position during an ignition cycle.

Action Taken When the DTC Sets

DTCs P0335 and P0336 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0335 and P0336 are Type B DTCs.

Diagnostic Aids

The following conditions could also set the DTCs:

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Circuit/System Verification

1. Clear the DTC Info with a scan tool. Attempt to start the engine, observe the DTC information with a scan tool. DTC P0335 or P0336 should not set.
2. Move related harnesses/connectors of the CKP sensor and verify the engine does not stumble, stall, or change engine speed.
3. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records List.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the crankshaft position (CKP) sensor.
2. Ignition ON, measure for 2-3 volts between the high signal circuit terminal 1 and ground.

⇒	If less than the specified range, test the high signal circuit for an open/high resistance or for a short to ground. If the circuits/connections test normal, replace the ECM.

⇒	If greater than the specified range, test the high signal circuit for a short to voltage. If the circuits/connections test normal, replace the ECM.

3. Ignition ON, measure for 2-3 volts between the low signal circuit terminal 2 and ground.

⇒	If less than the specified range, test the low signal circuit for an open/high resistance or for a short to ground. If the circuits/connections test normal, replace the ECM.

⇒	If greater than the specified range, test the low signal circuit for a short to voltage. If the circuits/connections test normal, replace the ECM.

4. If all circuits/connections test normal, test or replace the CKP sensor.

Component Testing

1. Ignition OFF, disconnect the harness connector at the crankshaft position (CKP) sensor.

Important: If the CKP sensor lead is damaged in any way, replace the CKP sensor.

2. Test for 700-1200 ohms of resistance between the high signal terminal 1 and the low signal terminal 2 of the CKP sensor.

⇒	If the resistance is not within the specified range, replace the CKP sensor.

3. Set the DMM to the AC voltage scale.
4. While cranking the engine, test for more than 1.3 ACV between the high signal terminal 1 and the low signal terminal 2 of the CKP sensor.

⇒	If less than 1.4 ACV, replace the CKP sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.