P0365 moderate

Ignition Coil K Primary/Secondary Circuit

The P0365 code means the vehicle's onboard diagnostic system has detected: Ignition Coil K Primary/Secondary Circuit. 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 on
  • Misfire on cylinder 11
  • V12 engine rough running
  • Power loss

Probable Causes (Ranked by Likelihood)

  • Faulty ignition coil K (cylinder 11) Very High
  • Damaged wiring High
  • Worn spark plug Moderate
  • PCM driver failure Low

Step-by-Step Diagnostic Procedure

  1. Check for misfire code on cylinder 11.

  2. Swap coil K with adjacent coil.

  3. Inspect spark plug.

  4. Measure coil resistance.

Frequently Asked Questions

What engines have coil K?

Only V12 engines have ignition coils K and L, serving cylinders 11 and 12.

Are V12 coils expensive?

V12 coils for luxury and exotic cars typically cost $60-$200 each, with labor costs of $200-$800 per coil depending on accessibility.

Can a V12 misfire be hard to detect?

Yes, V12 engines are very smooth, and a single cylinder misfire may be subtle at idle. It becomes more noticeable under load.

Sources

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

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