Ignition Coil Primary Control Circuit High Voltage
The P2316 code indicates that the powertrain control module (PCM) has detected a voltage higher than expected in the primary circuit of a specific ignition coil. This circuit controls the coil's ground path to fire the spark plug. A high voltage condition suggests an open or high resistance in the wiring, a faulty ignition coil, or a problem with the PCM driver. This can cause misfires, poor performance, and increased emissions.
01. Most Common Causes
- Faulty ignition coil
- Open or shorted wiring in the primary control circuit
- Poor electrical connection at the coil or PCM
- Failed PCM (rare)
02. Symptoms You Will Notice
- Engine misfire or rough idle
- Check Engine Light illuminated
- Reduced engine power and fuel economy
- Hard starting or stalling
03. Step-by-Step Diagnosis
Step 1: Scan for codes and note which cylinder is affected.
Step 2: Visually inspect the ignition coil and wiring for damage, corrosion, or loose connections.
Step 3: Use a multimeter to test the primary circuit resistance of the suspect coil (specs vary, typically 0.5-2 ohms).
Step 4: Swap the suspect coil with another cylinder and see if the code follows.
Step 5: If wiring and coil are good, test the PCM output with a test light or oscilloscope.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended. Driving with a misfire can damage the catalytic converter and cause poor performance.
How much does it cost to fix?▼
Typically $50-$150 for a DIY coil replacement; labor adds $50-$100 if done by a shop.