Ignition Coil H Primary Control Circuit High
What does P2315 mean?
The P2315 code means the vehicle's onboard diagnostic system has detected: Ignition Coil H Primary Control Circuit High. This is a moderate severity code.
Common Symptoms
- Cylinder 8 misfire detected
- Check Engine Light illuminated
- Engine rough at idle and under load
- Loss of performance during acceleration
- Higher emissions from tailpipe
Probable Causes (Ranked by Likelihood)
- Short circuit in coil H wiring Very High
- Internally shorted ignition coil H High
- Fluid contamination in spark plug well Moderate
- ECM coil driver transistor failure Low
Step-by-Step Diagnostic Procedure
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Check cylinder 8 spark plug well for oil or water
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Swap coil H to verify it is the faulty component
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Inspect wiring for shorts to ground or power
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Measure coil resistance and compare to specification
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Check valve cover gaskets for oil leaks into plug tubes
Frequently Asked Questions
Can I drive with code P2315?
Short distances only. Get the coil replaced soon to prevent catalytic converter damage from the cylinder 8 misfire.
What causes P2315?
Usually a failed or shorted ignition coil. On large V8 engines, heat cycling causes coil degradation over time especially at higher mileages.
Is P2315 expensive to fix?
Typically $50 to $400. Coil replacement is affordable. If oil is present in the plug well, valve cover gasket replacement adds cost.