P0315

DTC P0315: 58X Crank Position Tooth Error Not Learned

Circuit Description
In order to detect engine misfire at higher engine speeds, the Engine Control Module (ECM) must know of any variation between the crankshaft sensor pulses. Most variations are due to the machining of the crankshaft reluctor wheel. However, other sources of variation are also possible. A Crankshaft Position (CKP) system variation learning procedure must be performed any time a change is made to the crankshaft sensor to crankshaft relationship or if the ECM is replaced or reprogrammed. The ECM measures the variations and then calculates compensation factors needed to enable the ECM to accurately detect engine misfire at all speeds and loads. A scan tool must be used to command the ECM to learn these variations. If for any reason the ECM is unable to learn these variations or they are out of an acceptable range, the ECM will set Diagnostic Trouble Code (DTC) P1336. An ECM that has not had the CKP system variation learning procedure performed due to replacement or reprogramming will also set DTC P0315.

Conditions for Setting the DTC
- Tooth error not learned if the manufacture enable counter is set to zero.
- 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.

Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will illuminate.
- The ECM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame and Failure Records buffer.
- A history DTC is stored.

Conditions for Clearing the MIL/DTC
- The MIL will turn OFF after four consecutive ignition cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- Disconnecting the ECM battery feed for more than 10 seconds.
- The DTC(s) can be cleared by using the scan tool.

Diagnostic Aids

NOTE:
The On-Board Diagnostic (OBD II) System Check prompts the technician to complete some basic checks and store the Freeze Frame and Failure Records data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored on the scan tool for later reference.

1) Engine temperature is critical to properly learn the CKP system variation. Failure to properly warm the engine before performing this procedure will result in an inaccurate measurement of the CKP system variation The ECM learns this variation as the engine is decelerating and then allows engine control to be returned to the operator. All accessories must be OFF when learning the CKP system angle variation. If the A/C is not disabled when the learn procedure is enable, the ECM will disable the A/C.

2) If after the specified number attempts the ECM cannot learn the CKP system variation, then the variation is too large and no further attempts should be made until the variation problem is corrected.

3) Being unable to learn the procedure indicates that the variation is out of range.

4) After the CKP system variation has been learned, wait above 10 seconds with ignition switch OFF to prevent being cleared the learned value.

Test Description
The number(s) below refer to step(s) on the diagnostic table.
(1) The On-Board Diagnostic (OBD II) System Check prompts the technician to complete some basic checks and store the freeze frame and failure records data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored on the scan tool for later reference.
(2) Engine temperature is critical to properly learn the CKP system variation. Failure to properly warm the engine before performing this procedure will result in an inaccurate measurement of the CKP system variation. The ECM learns this variation as the engine is decelerating and then allows engine control to be returned to the operator. All accessories must be OFF when learning the CKP system angle variation. If the A/C is not disabled when the learn procedure is enabled, the ECM will disable the A/C.
(3) Being unable to learn the procedure indicates that the variation is out of range.
(4) If after the specified number attempts the ECM cannot learn the CKP system variation, then the variation is too large and no further attempts should be made until the variation problem is corrected.

Steps 1-6:

Troubleshooting