B Camshaft Position - Actuator Circuit (Bank 2)
Diagnostic trouble code P0023 indicates that the Engine Control Module (ECM) has detected an electrical malfunction in the Bank 2 exhaust (B) camshaft position actuator circuit. The ECM sets this code when the voltage or resistance in the actuator control circuit falls outside of the expected manufacturer specifications.
While the vehicle can usually still be driven, this code should be addressed soon to restore proper engine performance and prevent potential long-term wear. Driving with improper camshaft timing can lead to poor fuel economy and rough running conditions.
Common symptoms
- Illuminated Check Engine Light
- Rough or unstable engine idle
- Hesitation or poor acceleration
- Decreased fuel economy
- Occasional engine stalling
Likely causes
- Low engine oil level or dirty, degraded oil
- Faulty Bank 2 exhaust camshaft position actuator solenoid (VVT valve)
- Corroded, damaged, or loose wiring and connectors in the actuator circuit
- Sludge buildup blocking the VVT solenoid oil passages
- Internal mechanical failure in the camshaft phaser
- Faulty Engine Control Module (ECM)
What to check before replacing parts
Check the engine oil level and condition.
Look for: Low oil levels or excessively dirty, sludged oil can prevent the hydraulic VVT system from operating correctly.
Visually inspect the wiring and connector at the Bank 2 exhaust camshaft actuator solenoid.
Look for: Look for frayed wires, melted insulation, or corroded pins that would cause an open or short circuit.
Measure the internal resistance of the Bank 2 exhaust VVT solenoid using a multimeter.
Look for: Compare the resistance reading to the manufacturer's specification; an infinite reading indicates an open internal coil, while a very low reading indicates a short.
Check for proper power and ground signals at the solenoid connector with the key on.
Look for: A lack of 12-volt power or a missing ground control signal from the ECM indicates a wiring harness issue or a blown fuse.
Use a bi-directional scan tool to command the Bank 2 exhaust VVT solenoid on and off.
Look for: Listen for a clicking sound from the solenoid or observe changes in engine idle; no change indicates a stuck solenoid or circuit failure.
This page explains the generic P0023 definition and is general reference information, not a diagnosis for your specific vehicle. Actual causes, severity, and repairs vary by make, model, engine, and mileage — always confirm with a scan tool and a qualified technician before replacing parts.
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