P0315
DTC P0315
CIRCUIT DESCRIPTION
The crankshaft position (CKP) system variation learn feature is used to calculate reference period errors caused by slight tolerance variations in the crankshaft, and the CKP 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 wide range of engine speed and load. The ECM stores the Crankshaft Position System Variation values after a learn procedure has been performed. If the actual crankshaft position variation is not within the Crankshaft Position System Variation compensating values stored in the ECM, DTC P0300 may set. If the CKP system variation values are not stored in the ECM memory, DTC P0315 sets.
DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC P0315 Crankshaft Position (CKP) System Variation Not Learned
CONDITIONS FOR RUNNING THE DTC
- DTCs P0335, P0336, or P0341, are not set.
- DTC P0315 runs continuously.
CONDITIONS FOR SETTING THE DTC
- The CKP system variation values are not stored in the ECM memory.
- The enable counter equals 0.
ACTION TAKEN WHEN THE DTC SETS
- The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
- The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.
CONDITIONS FOR CLEARING THE MIL/DTC
- A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
- Clear the MIL and the DTC with a scan tool.
TEST
