P265B: B Rocker Arm Actuator Position Sensor Circuit Range/Performance Bank 1
The P265B code indicates that the Engine Control Module (ECM) has detected a range or performance issue in the B rocker arm actuator position sensor circuit on Bank 1. This sensor monitors the position of the rocker arm actuator, which controls variable valve timing or cylinder deactivation. A fault can cause incorrect actuator operation, leading to reduced engine performance, increased emissions, and potential drivability issues.
01. Most Common Causes
- Faulty rocker arm actuator position sensor
- Wiring or connector issues in the sensor circuit
- Failed rocker arm actuator
- ECM software or hardware problem
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine power or performance
- Rough idle or misfire
- Decreased fuel economy
03. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for additional codes.
Step 2: Visually inspect the wiring and connectors for damage, corrosion, or loose connections.
Step 3: Test the sensor's voltage and resistance with a multimeter and compare to manufacturer specs.
Step 4: If sensor and wiring are okay, test the actuator operation and replace if faulty.
Step 5: Clear the code and test drive to see if it returns; if so, further ECM diagnosis may be needed.
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 valve train. Have it diagnosed promptly.
How much does it cost to fix?▼
Repair costs typically range from $150 to $400, depending on the cause (sensor replacement vs. actuator replacement) and labor rates.