P2301 moderate

Ignition Coil A Primary Control Circuit High

The P2301 code means the vehicle's onboard diagnostic system has detected: Ignition Coil A Primary Control Circuit High. 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 associated with coil A
  • Check Engine Light illuminated or flashing
  • Rough running engine
  • Loss of power during acceleration
  • Increased exhaust emissions

Probable Causes (Ranked by Likelihood)

  • Short circuit in ignition coil A wiring Very High
  • Failed ignition coil A (shorted internally) High
  • Damaged coil A connector with shorted pins Moderate
  • ECM coil driver transistor failure Low

Step-by-Step Diagnostic Procedure

  1. Swap coil A with another cylinder coil to confirm the coil is at fault

  2. Check coil connector pins for shorts between terminals

  3. Measure primary coil resistance and compare to specification

  4. Inspect wiring for chafing or melted insulation near exhaust heat

  5. Test the ECM coil driver output with a noid light

Frequently Asked Questions

Can I drive with code P2301?

Short distances only. Continued misfiring can overheat and damage the catalytic converter. Do not ignore a flashing Check Engine Light.

What causes P2301?

Usually a failed ignition coil or shorted wiring. The coil swap test is the fastest way to confirm whether the coil itself is the problem.

Is P2301 expensive to fix?

Typically $50 to $300. Ignition coil replacement is one of the more affordable engine repairs.

Sources

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

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