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 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.

The ECM stores the CKP system variation values after a learn procedure has been performed. If the actual CKP variation is not within the CKP system variation compensating valves 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 P0106, P0107, P0108, P0117, P0118, P0122, P0123, P0132, P0201, P0202, P0203, P0204, P0324, P0327, P0336, P0337, P0341, P0342, P0351, P0352, P0402, P0404, P0405, P0406, P0488, P0502, and P0700 are not set.
* The engine coolant temperature (ECT) is more than 65°C (149°F).
* DTC P0315 runs continuously once the above conditions are met.

Conditions for Setting the DTC

* The CKP system variation values are not stored in the ECM memory.
* The manufacturer enable counter is set to zero.

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

* The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
* 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 Description

The number below refers to the step number on the diagnostic table.
2. The Crankshaft Position Variation Learn Procedure may have to be repeated up to 5 times before the procedure is learned.