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CKP System Variation Learn Procedure

NOTE: The Crankshaft Position (CKP) system variation learn procedure is required when the following service procedures have been performed, regardless of whether DTC P0315 is set:
  • CKP sensor replacement.
  • Engine replacement.
  • PCM replacement.
  • Harmonic balancer replacement.
  • Crankshaft replacement.
  • Any engine repairs which disturb the CKP sensor relationship.

For additional diagnostic information, see DTC P0315: CRANKSHAFT POSITION SENSOR VARIATION NOT LEARNED under DIAGNOSTIC TESTS in SELF-DIAGNOSTICS - 4.8L, 5.3L & 6.0L "C", "K" & "N" SERIES article.

  1. Install a scan tool to Data Link Connector (DLC).
  2. With a scan tool, monitor the powertrain control module for DTCs. If only DTC P0315 is set, go to next step. If a DTC other than P0315 is set, diagnose that DTC first. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 4.8L, 5.3L & 6.0L "C", "K" & "N" SERIES article.
  3. With a scan tool, select the CRANKSHAFT POSITION VARIATION LEARN PROCEDURE.
  4. The scan tool instructs you to perform the following:
    • Set parking brake.
    • Block drive wheels.
    • DO NOT apply brake pedal.
    • Observe fuel cut-off for applicable engine.
    • Accelerate to Wide Open Throttle (WOT).
    • Release throttle when fuel cut-off occurs.
    • Engine should not accelerate beyond calibrated RPM value.
    • Release throttle immediately if value is exceeded.
    • Cycle ignition from OFF to ON.
    • Apply and hold brake pedal.
    • Start and idle engine.
    • Turn A/C OFF.
    • Vehicle must remain in Park or Neutral.
    • 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:
      1. Crankshaft Position (CKP) sensor activity. If there is a CKP sensor condition, refer to the applicable DTC that set. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 4.8L, 5.3L & 6.0L "C", "K" & "N" SERIES article.
      2. Camshaft Position (CMP) sensor activity. If there is a CMP sensor condition, refer to the applicable DTC that set. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 4.8L, 5.3L & 6.0L "C", "K" & "N" SERIES article.
      3. 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.
  5. With the scan tool, enable the crankshaft position system variation learn procedure.
    6. 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.
  6. Slowly increase the engine speed to the RPM that you observed.
  7. Immediately release the throttle when fuel cut-off is reached.
  8. The scan tool displays Learn Status: Learned this ignition. If the scan tool does NOT display this message and no additional DTCs set, see DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article. If a DTC set, see DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 4.8L, 5.3L & 6.0L "C", "K" & "N" SERIES article.
  9. Turn OFF the ignition for 30 seconds after the learn procedure is completed successfully.
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