P264D: Rocker Arm Actuator Position Sensor Circuit High Bank 1
The P264D code indicates that the Engine Control Module (ECM) has detected a high voltage signal from the rocker arm actuator position sensor on Bank 1. This sensor monitors the position of the rocker arm actuator, which controls variable valve timing or cylinder deactivation. A high circuit condition typically means the signal voltage is above the expected range, often due to a short to voltage, faulty sensor, or wiring issues. This can lead to improper valve operation, affecting engine performance and fuel economy.
1. Most Common Causes
- Faulty rocker arm actuator position sensor (oil pressure switch) internally damaged or contaminated with oil debris
- Signal wire shorted to battery voltage (B+) or to the 5V reference circuit
- Sensor ground circuit has excessive resistance, is corroded, or open
- Sensor electrical connector damaged, with bent pins or moisture/corrosion ingress
- Mechanical failure or oil deposit blockage in the rocker arm actuator or VTEC oil control solenoid valve
- Low engine oil level, incorrect oil viscosity, or severely contaminated/deteriorated oil
- PCM internal failure or need for calibration update (rare)
2. Symptoms You Will Notice
- Check Engine Light on
- Reduced engine performance
- Poor fuel economy
- Engine misfire or rough idle
3. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect the sensor and wiring for damage or corrosion.
Step 3: Test sensor voltage and ground with a multimeter.
Step 4: Compare sensor signal voltage to manufacturer specifications.
Step 5: If sensor is faulty, replace it and clear codes.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can cause engine performance issues and potential damage to the valve train.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and sensor replacement, depending on labor rates and parts.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.