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P0361 — Ignition Coil K Primary Control Circuitopen

Generic OBD-II · all makesPowertrain (engine & transmission)

P0361 indicates that the engine computer has detected a break in continuity (an open circuit) in the primary control circuit for ignition coil "K". This means the specified cylinder's coil is not receiving the proper electrical signal to fire the spark plug, which typically results in an engine misfire.

Symptoms

What causes it — most likely first

1. Failed ignition coil

The internal primary winding of the coil has broken, creating the open circuit detected by the engine computer.

2. Open or broken wiring

A physical break, severe chafing, or disconnected wire in the primary control circuit between the coil and the engine computer.

3. Corroded or loose connector

Poor contact at the coil or engine computer connector, such as a pushed-back pin or corrosion, prevents the circuit from completing.

4. Failed PCM/ECM

The internal driver for the ignition coil inside the engine computer has failed, though this is extremely rare compared to wiring or coil failures.

How it's diagnosed

  1. Scan for additional codes and document freeze frame data to understand the operating conditions when the fault occurred.
  2. Locate ignition coil "K" based on the specific vehicle's firing order and cylinder numbering scheme outlined in the service manual.
  3. Visually inspect the coil connector and wiring harness for obvious damage, corrosion, or disconnected pins.
  4. Test the primary circuit continuity between the coil connector and the engine computer to pinpoint the exact location of the open.
  5. Swap the suspected coil with an adjacent cylinder's coil to see if the misfire or code follows the coil, confirming coil failure.
  6. If the wiring and coil test fine, check the PCM connector pins and evaluate the PCM driver output directly as a last resort.

Code facts & related codes

SystemPowertrain (engine & transmission)
StandardizationSAE generic — identical on every make

Frequently asked

Can I drive with a P0361 code?

It is not recommended. A misfiring cylinder can cause unburned fuel to enter the catalytic converter, which can overheat and cause costly damage over time.

What does 'Ignition Coil K' mean?

The letter 'K' designates a specific cylinder based on the manufacturer's numbering system (often the 11th cylinder in the sequence A=1, B=2, etc.). You must consult a service manual to identify which physical cylinder this refers to on your specific engine.

Does P0361 mean my engine computer (PCM) is bad?

Rarely. While a failed PCM driver can cause an open circuit code, it is much more likely that the ignition coil itself has failed internally or there is a broken wire or bad connection in the circuit. The PCM should be the absolute last component tested and replaced.

Is replacing the ignition coil a permanent fix?

If the coil itself was the root cause, yes. However, if the underlying issue is damaged wiring or a poor connection that caused the coil to fail, the new coil may also fail if the circuit problem is not addressed first.