Lucerne V6-3.9L (2009)
Crankshaft Position Sensor: Service and Repair
Crankshaft Position System Variation Learn
Crankshaft Position System Variation Learn
Note: The crankshaft position system variation learn procedure is also required when the following service procedures have been performed, regardless
of whether DTC P0315 is set:
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An engine replacement
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A engine control module (ECM) replacement
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A crankshaft balancer replacement
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A crankshaft replacement
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A crankshaft position sensor replacement
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Any engine repairs which disturb the crankshaft to crankshaft position sensor relationship.
Note: The ECM monitors certain component signals to determine if all the conditions are met to continue with the Crankshaft Position System Variation
Learn Procedure. The scan tool only displays the condition that inhibits the procedure. The scan tool displays the signals of the following components:
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Crankshaft position sensors activity-If there is a crankshaft position sensor condition, refer to the applicable DTC that set.
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Camshaft position signal activity-If there is a camshaft position signal condition, refer to the applicable DTC that set.
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Engine coolant temperature (ECT)-If the engine coolant temperature is not warm enough, idle the engine until the engine coolant temperature
reaches the correct temperature.
1. Install a scan tool.
2. Monitor the ECM for DTCs with a scan tool. If other DTCs are set, except DTC P0315, refer to Diagnostic Trouble Code (DTC) List - Vehicle (
See: Testing and Inspection/Diagnostic Trouble Code Descriptions) for the applicable DTC that set.
3. With a scan tool, select the Crankshaft Position System Variation Learn Procedure and perform the following:
1. Block drive wheels.
2. Set parking brake.
3. DO NOT apply brake pedal.
4. Cycle ignition from OFF to ON.
5. Apply and hold brake pedal for the duration of the procedure.
6. Start and idle engine.
7. Turn the air conditioning (A/C) OFF.
8. The vehicle must remain in Park or Neutral.
Note: While 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.
9. Accelerate to wide open throttle (WOT) and release when the fuel cut-off occurs.
4. The scan tool displays Learn Status: Learned this Ignition. If the scan tool indicates that DTC P0315 ran and passed, the crankshaft position
variation learn procedure is complete. If the scan tool indicates DTC P0315 failed or did not run, or another DTC is present, refer to Diagnostic
Trouble Code (DTC) List - Vehicle (See: Testing and Inspection/Diagnostic Trouble Code Descriptions) and perform the appropriate diagnostic
procedure.
5. Turn OFF the ignition for 30 s after the learn procedure is completed successfully in order to store the crankshaft position system variation values
in the ECM memory.
