Ignition Coil Primary Control Circuit High
The P2307 code indicates that the engine control module (ECM) has detected a high voltage condition in the primary control circuit of a specific ignition coil. This circuit controls the coil's ground path to fire the spark plug. A high voltage reading suggests a short to power, open circuit, or faulty coil driver within the ECM. This can cause misfires, poor performance, and increased emissions.
01. Most Common Causes
- Faulty ignition coil
- Short to voltage in wiring or connector
- Failed ECM (internal coil driver)
02. Symptoms You Will Notice
- Engine misfire or rough idle
- Check Engine Light illuminated
- Reduced fuel economy and power
03. Step-by-Step Diagnosis
Step 1: Scan for codes and note which cylinder is affected.
Step 2: Visually inspect the ignition coil connector and wiring for damage or corrosion.
Step 3: Swap the suspect coil with another cylinder and see if the code follows.
Step 4: If code stays, test for voltage at the coil connector with key on; expect battery voltage on power wire and a pulsed ground from ECM.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended as it can cause misfires, catalytic converter damage, and poor drivability. Have it diagnosed promptly.
How much does it cost to fix?▼
Typically $50-$150 for a DIY coil replacement; labor adds $50-$100 if done by a shop.