DTC P0315: Crankshaft Position Sensor Variation Not Learned: Description
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The Crankshaft Position Sensor (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 Powertrain Control Module (PCM) to detect misfire events over a wide range of engine speed and load. If the CKP system variation values are not stored in the PCM memory, DTC P0315 sets.