The crankshaft position (CKP) sensor circuits consist of an engine control module (ECM) supplied 5-volt reference circuit, low reference circuit and an output signal circuit. The CKP sensor is an internally magnetic biased digital output integrated circuit sensing device. The sensor detects magnetic flux changes of the teeth and slots of a 58-tooth reluctor wheel on the crankshaft. Each tooth on the reluctor wheel is spaced at 60-tooth spacing, with 2 missing teeth for the reference gap. The CKP sensor produces an ON/OFF DC voltage of varying frequency, with 58 output pulses per crankshaft revolution. The frequency of the CKP sensor output depends on the velocity of the crankshaft. The CKP sensor sends a digital signal, which represents an image of the crankshaft reluctor wheel, to the ECM as each tooth on the wheel rotates past the CKP sensor. The ECM uses each CKP signal pulse to determine crankshaft speed and decodes the crankshaft reluctor wheel reference gap to identify crankshaft position. This information is then used to sequence the ignition timing and fuel injection events of the engine. The ECM also uses CKP sensor output information to determine the camshaft relative position to the crankshaft, to control camshaft actuator, and to detect cylinder misfire

Important: The ECM 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.

P0335

P0336

DTCs P0335 and P0336 are Type B DTCs.

DTCs P0335 and P0336 are Type B DTCs.

This test procedure requires that the vehicle battery has passed a load test and is completely charged.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Description and Operation

Electronic Ignition (EI) System Diagnosis

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

1. With the ignition OFF, inspect the engine wiring harnesses carrying the CKP sensor circuits for the following conditions:

•	Close routing of aftermarket electrical equipment

•	Close to solenoids, motors, and relays

⇒	Correct any wire harness routing or component placement conditions, if it is determined to be a possible source of electrical interference.

2. With the ignition ON, and the engine OFF, use the live plot function on the scan tool. Select the engine speed parameter and the CKP sensor parameter. Change the minimum spec to 400 RPM for both parameters. Change the maximum spec to 4,000 RPM for both parameters.
3. Start the engine and observe the scan tool.
4. Quickly accelerate and release the accelerator pedal several times. DO not accelerate pass 4,000 RPM. Two graphed lines on the live plot display should track together across the screen.

⇒	If the vehicle passes the Circuit/System Verification Test, 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 data list.

5. Engine running, observe the DTC information with a scan tool. DTCs P0335 or P0336 should not set.
6. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

P0335

1. Ignition OFF, disconnect the 8 way harness connector C104.
2. Test for less than 1 ohm of resistance between low reference circuit terminal A on the ECM side of the connector and ground.

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

3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal C on the ECM side of the connector and ground.

⇒	If less than the specified range, test the 5-volt reference circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the ECM.

⇒	If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.

4. Ignition ON, test for 4.8-5.2 volts between the signal circuit terminal B on the ECM side of the connector and ground.

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

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

5. Ignition OFF, connect a fused jumper wire connected to the CKP signal circuit terminal B on the ECM side of the connector.
6. Ignition ON, momentarily touch the end of the fused jumper wire to the negative battery post. The CKP active counter parameter on the scan tool should increment.

⇒	If the CKP Active Counter parameter does not increment, replace the ECM.

7. Ignition OFF, inspect the wiring harness, from the 8-way connector C104 to the CKP sensor, for any damage, opens, or shorts.

⇒	If the circuits test normal replace the CKP sensor.

P0336

1. Ignition OFF, inspect the CKP sensor for correct installation.

⇒	If the sensor is loose, inspect the sensor and the O-ring for damage, replace as necessary.

2. Inspect the engine for the following conditions:

•	The engine oil for debris

•	The crankshaft reluctor wheel for damage

•	The timing chain, tensioner, and sprockets for wear or damage

Important: You must perform the Circuit/System Testing before proceeding with Component Testing.

1. Inspect the CKP sensor for correct installation. Remove the CKP sensor from the engine and inspect the sensor and the O-ring for damage.

⇒	If the sensor is loose, incorrectly installed, or damaged; repair or replace the CKP sensor.

2. Connect the CKP Sensor connector to the CKP sensor. Turn ON the ignition, with the engine OFF.
3. Ignition ON and engine OFF. Observe the CKP Active Counter while passing a steel object across the tip of the sensor repeatedly. The CKP Active Counter parameter should increment.

⇒	If the parameter does not increment, replace the CKP sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.