What Does P266C Mean?
The rocker arm actuator position sensor on Bank 2 is reporting a voltage signal below the expected minimum threshold. This sensor monitors the position of variable valve timing components. Low voltage indicates a potential short to ground or sensor failure.
Common Causes
35%
Damaged or shorted wiring harness between ECM and rocker arm actuator position sensor
30%
Faulty rocker arm actuator position sensor
20%
Poor electrical connection or corroded connector at sensor
10%
Short to ground in sensor circuit
5%
Failed Engine Control Module (ECM)
Diagnostic Steps
1
Step 1: Visually inspect wiring harness and connector at Bank 2 rocker arm actuator position sensor for damage, corrosion, or loose connections
2
Step 2: Measure voltage at sensor connector with ignition on; verify reference voltage (typically 5V) is present from ECM
3
Step 3: Check sensor ground circuit for continuity to ground and verify resistance is less than 1 ohm
4
Step 4: Disconnect sensor and measure resistance across sensor terminals; compare to manufacturer specifications
5
Step 5: If all circuits test good, replace rocker arm actuator position sensor and retest
Estimated Repair Cost
$150 - $600
Parts + labor, varies by vehicle and location
The rocker arm actuator position sensor on Bank 2 is reporting a voltage signal below the expected minimum threshold. This sensor monitors the position of variable valve timing components. Low voltage indicates a potential short to ground or sensor failure.
The most common cause of P266C (A Rocker Arm Actuator Position Sensor Circuit Low Bank 2) is: Damaged or shorted wiring harness between ECM and rocker arm actuator position sensor
Typical repair costs for P266C range from $150 to $600, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Vehicle is generally safe to drive but may experience reduced engine performance, poor fuel economy, and rough idle. Prolonged operation may cause engine damage due to improper valve timing.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P266C to identify the root cause.
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Quick Info
Category
Powertrain
System
Variable Valve Timing System
Difficulty
Type
Generic (SAE)
Recommended Tools
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