P0366 moderate

Ignition Coil K Primary/Secondary Circuit - No Activity

The P0366 code means the vehicle's onboard diagnostic system has detected: Ignition Coil K Primary/Secondary Circuit - No Activity. This is a moderate severity code.

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Keep driving?
Short distances only
DIY difficulty
moderate
Estimated cost
$80 - $400 (parts and labor)
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Common Symptoms

  • Check Engine Light illuminated
  • Dead misfire on cylinder 11
  • No spark to cylinder 11
  • Slight vibration from V12

Probable Causes (Ranked by Likelihood)

  • Dead ignition coil K Very High
  • Open circuit High
  • Disconnected connector Moderate
  • PCM driver failure Low

Step-by-Step Diagnostic Procedure

  1. Check connector.

  2. Measure coil resistance.

  3. Test PCM trigger signal.

  4. Replace coil if dead.

Frequently Asked Questions

Is P0366 an emergency?

Not immediately, but repair within a few days. Running a V12 with a dead cylinder can damage the catalytic converter on that bank.

Do W12 engines use the same codes?

Yes, W12 engines like the Bentley 6.0L use the same cylinder numbering and OBD-II codes as V12 engines.

Can I drive a V12 with P0366?

Short distances only. The engine will run but with reduced power and potential exhaust damage.

Sources

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

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