Fault Family
System: Powertrain (P-Codes)
3 SAE Codes
Crank Position Variation Learn
Diagnostic & Technical Explanation
Code P0315 (Crankshaft Position System Variation Not Learned) sets when the ECM's crankshaft tooth-to-tooth variation learn procedure has not completed successfully, or the module cannot correctly determine the crankshaft's start position or rotational direction from the reluctor pattern. This is a learned-calibration fault rather than a simple open/short: causes are a battery disconnect or reflash that erased the prior learn, a reluctor wheel with worn or damaged teeth preventing a stable pattern, or a failing sensor with a marginal air gap that the relearn procedure cannot tolerate.
These 3 diagnostic trouble codes share one
detection mechanism and one repair path, which is why MechanicDB groups them into a single
authored fault family rather than repeating the same explanation 3 times.
What this page does not show
This page publishes the fault mechanism and the code index. The licensed dataset adds, for
every one of the 15,886 codes, the full authored repair set (56,729 procedures in total)
with the fields deliberately withheld here:
- Procedures 2..n after the first-listed procedure
- Aftermarket parts cost ranges in USD (
est_parts_cost_min/max_usd)
- Professional labor-hour estimates (
est_labor_hours)
- Step-by-step diagnostic and repair instructions
- Replacement-part mappings and catalog lookups
- 6,637 manufacturer-specific OEM codes across 32 makes ($149 tier)