P2302 moderate

Ignition Coil B Primary Control Circuit Low

The P2302 code means the vehicle's onboard diagnostic system has detected: Ignition Coil B Primary Control Circuit Low. This is a moderate severity code.

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Keep driving?
Short distances only
DIY difficulty
moderate
Estimated cost
$50 - $300 (parts and labor)
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Common Symptoms

  • Engine misfire on cylinder 2
  • Check Engine Light flashing
  • Rough idle and engine vibration
  • Reduced power output
  • Smell of unburned fuel from exhaust

Probable Causes (Ranked by Likelihood)

  • Failed ignition coil B Very High
  • Damaged wiring to ignition coil B High
  • Corroded coil B connector Moderate
  • ECM coil driver circuit fault Low

Step-by-Step Diagnostic Procedure

  1. Swap coil B with another cylinder coil to verify the fault follows

  2. Check coil B connector for corrosion or damage

  3. Measure coil B primary resistance

  4. Inspect wiring harness to coil B for damage

  5. Also replace the spark plug if it appears worn or fouled

Frequently Asked Questions

Can I drive with code P2302?

Short distances only. Stop driving immediately if the Check Engine Light is flashing, as this indicates active catalyst-damaging misfires.

What causes P2302?

Usually a failed ignition coil on cylinder 2. Replace the spark plug at the same time since a worn plug can contribute to coil failure.

Is P2302 expensive to fix?

Typically $50 to $300. Coil and spark plug replacement together is a common repair that most DIY mechanics can handle.

Sources

This page is built from documented references. Verify against your own service info before repair work.

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