Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

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 determine the optimum ignition and injection points of the engine. The ECM also uses CKP sensor output information to determine the camshaft relative position to the crankshaft, to control camshaft phasing, 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

DTC P0335 and P0336 are Type B DTCs

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Electrical Information Reference

Scan Tool Reference

Description and Operation

Electronic Ignition (EI) System Description

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

•	Close routing of secondary ignition wires

•	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 engine running, observe the Engine Speed parameter using the scan tool. Operate the engine from idle up to 3,000 RPM. The Engine Speed parameter should match the CMP Sensor parameter within 100 RPM.

P0335

1. Disconnect the CKP sensor connector.
2. Test for less than 1.0 ohm of resistance between low reference circuit 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 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 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 ON, using a jumper wire connected to ground, momentarily touch the CKP sensor signal circuit repeatedly. The CKP Active Counter parameter should increment

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

P0336

1. Ignition OFF, inspect the CKP sensor for looseness and 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:

•	Engine oil for debris

•	Crankshaft reluctor wheel for damage

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

⇒	If debris is found in the engine oil, inspect the internal engine components to determine the cause. Repair or replace any worn or damaged components. Refer to Camshaft Timing Chain and Sprocket Cleaning and Inspection and Crankshaft and Bearing Cleaning and Inspection .

1. Inspect the CKP sensor for looseness and correct installation. Remove the CMP 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. Observe the CKP Active Counter parameter on the scan tool; pass a steel object by the tip of the sensor repeatedly. The CKP Active Counter parameter should increment.

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

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.