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 sensors. The calculated error allows the powertrain control module (PCM) to accurately compensate for reference period variations. This enhances the ability of the PCM to detect misfire events over a wider range of engine speed and load.

The PCM stores the CKP system variation values after a learn procedure has been performed. If the actual CKP variation is not within CKP system variation compensating values stored in the PCM the DTC may set. If the CKP system variation values are not stored in the PCM memory, DTC P0315 sets.