DTC P0315
Diagnostic Instructions
DTC Descriptor
DTC P0315: Crankshaft Position System Variation Not Learned
Circuit/System Description
The crankshaft position system variation learn feature is used to calculate reference period errors caused by slight tolerance variations in the crankshaft, and the crankshaft position sensor. The calculated error allows the engine control module (ECM) to accurately compensate for reference period variations. This enhances the ability of the ECM to detect misfire events over a wider range of engine speed and load conditions.
The crankshaft position system variation compensating values are stored in ECM memory after a learn procedure has been performed and the ignition switch is turned to the OFF position for at least 30 s. If the actual variation is not within the crankshaft position system variation compensating values stored in the ECM, DTC P0300 may set.
If the crankshaft position system variation values are not stored in the ECM memory or a proper ECM power down does not occur after completing the Crankshaft Position Learn Procedure, DTC P0315 sets.
Conditions for Running the DTC
DTC P0315 runs continuously.
Conditions for Setting the DTC
The ECM detects that the crankshaft position system variation values are not stored in memory.
Action Taken When the DTC Sets
DTC P0315 is a Type A DTC.
Conditions for Clearing the MIL/DTC
DTC P0315 is a Type A DTC.
Diagnostic Aids
This test procedure requires that the vehicle battery has passed a load test and is completely charged. Refer to Battery Inspection/Test .
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End Views
Component Connector End Views
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
Note: The Crankshaft Position System Variation Learn Procedure may have to be repeated up to 5 times before the procedure is successful.
- Perform the Crankshaft Position System Variation Learn procedure. The scan tool should display Learned Successful.
⇒ | If the Crankshaft Position System Variation Learn Procedure cannot be performed successfully, inspect for the following conditions: |
• | Worn crankshaft main bearings |
• | A damaged or misaligned reluctor wheel |
• | Excessive crankshaft runout |
• | Interference in the signal circuit of the crankshaft position sensor |
• | The ignition switch is in the ON position until there is insufficient system voltage. |
• | An ECM power disconnect with the ignition ON that may have erased the crankshaft position system variation values and set DTC P0315 |
• | Debris between the crankshaft position sensor and the reluctor wheel |
- Verify the Learn Procedure is successful.
⇒ | If the ECM is unable to complete the learn procedure, replace the ECM. |
Repair Instructions
Perform the Diagnostic Repair Verification after using this diagnostic procedure.
Control Module References for engine control module replacement, programming, and setup.
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