Crankshaft Position System Variation Learn Procedure
- Install a scan tool.
- With a scan tool, monitor the powertrain control module for DTCs. If other DTCs are set, except DTC P1336, refer to Diagnostic Trouble Code (DTC) List for the applicable DTC that set.
- With a scan tool, select the crankshaft position variation learn procedure.
- Observe the fuel cut-off for the engine that you are performing the learn procedure on.
- The scan tool instructs you to perform the following:
- Block the drive wheels.
- Apply the vehicles parking brake.
- Cycle the ignition from OFF to ON.
- Apply and hold the brake pedal.
- Start and idle the engine (with A/C OFF).
- Place the vehicle's transmission in Park (A/T) or Neutral (M/T).
The scan tool monitors certain component signals to determine if all the conditions are met to continue with the procedure. The scan tool only displays the condition that inhibits the procedure. The scan tool monitors the following components:
Crankshaft position (CKP) sensors activity--If there is a CKP sensor condition, refer to the applicable DTC that set.
With the scan tool, enable the crankshaft position system variation learn procedure.
NOTEWhile the learn procedure is in progress, release the throttle immediately when the engine starts to decelerate. The engine control is returned to the operator and the engine responds to throttle position after the learn procedure is complete.
- Slowly increase the engine speed to the RPM that you observed.
- Immediately release the throttle when fuel cut-off is reached.
- The scan tool displays Learn Status: Learned this ignition. If the scan tool does NOT display this message and no additional DTCs set, refer to Symptom Diagnosis (No Codes) section . If a DTC set, refer to Diagnostic Trouble Code (DTC) List for the applicable DTC that set.
- Turn OFF the ignition for 30 seconds after the learn procedure is completed successfully.
The crankshaft position (CKP) sensor is a three wire sensor based on the magneto resistive principle. A magneto resistive sensor uses two magnetic pickups between a permanent magnet. As an element such as a reluctor wheel passes the magnets the resulting change in the magnetic field is used by the sensor electronics to produce a digital output pulse. This system uses two sensors within the same housing for the V6 engine, and two separate sensors for the V8 engine. The PCM supplies each sensor a 12-volt reference, low reference, and a signal circuit. The signal circuit returns a digital ON/OFF pulse 24 times per crankshaft revolution.
Removal & Installation
- Raise and support the vehicle.
- Remove the air deflector.
- Remove the oil filter adaptor.
- Disconnect the crankshaft position sensor electrical connector.
- Remove the crankshaft sensor retaining bolt.
Remove the crankshaft sensor.
Lubricate the crankshaft sensor O-ring with clean engine oil.
NOTEUse the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
- Install the crankshaft sensor and the retaining bolt. Tighten the retaining bolt between 10 Nm (89 inch lbs.).
- Connect the crankshaft position sensor electrical connector.
- Install the oil filter adaptor.
- Install the air deflector.
- Lower the vehicle.
- Operate the engine and inspect crankshaft sensor for engine oil leaks.
- Perform the CKP System Variation Learn Procedure.