P266C: Rocker Arm Actuator Position Sensor Circuit Low Bank 2
The P266C code indicates that the Engine Control Module (ECM) has detected a low voltage signal from the rocker arm actuator position sensor on Bank 2. This sensor monitors the position of the rocker arm actuator, which controls variable valve timing or cylinder deactivation. A low circuit condition typically means the signal voltage is below the expected range, often due to a short to ground, faulty sensor, or wiring issues. This can affect engine performance, fuel economy, and emissions.
01. Most Common Causes
- Faulty rocker arm actuator position sensor
- Short to ground in sensor circuit
- Damaged wiring or connector
- ECM failure (rare)
02. Symptoms You Will Notice
- Check Engine Light on
- Reduced engine power or performance
- Poor fuel economy
- Rough idle or misfire
03. Step-by-Step Diagnosis
Step 1: Scan for codes and freeze frame data
Step 2: Visually inspect wiring and connector for damage or corrosion
Step 3: Test sensor voltage and ground with a multimeter
Step 4: Compare sensor signal to manufacturer specifications
Step 5: Replace sensor if faulty, repair wiring if shorted
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can cause reduced engine performance and potential damage to the variable valve timing system.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for parts and labor, depending on the vehicle and shop rates.