P0023
"B" Camshaft Position Actuator Circuit/Open (Bank 2)
Moderate· Fix soonDIY friendlyPowertrainGeneric, all makes
What it means
The ECU has detected an electrical fault in the variable valve timing solenoid (oil control valve) for the exhaust camshaft on bank 2. This solenoid directs oil to the cam phaser to advance or retard valve timing.
Is it safe to drive?
Usually drivable short-term, but power and economy may suffer. If it comes with a rattle on start-up or other timing codes, get it checked soon: a stretched timing chain can jump and cause serious engine damage.
Symptoms
- Check engine light on
- Rough idle
- Reduced power and poor fuel economy
- Rattle from the engine on cold start (chain wear)
- Possible stalling
Probable causes
Most likely first
- 1Failed VVT solenoid (open or shorted coil)
- 2Damaged or oil-soaked connector
- 3Open or shorted wiring
- 4ECU driver fault (rare)
How to diagnose it
Work through these in order before buying parts
- 1Record the code and its freeze frame data (speed, load, temperature when it set), then clear it and see if it comes back.
- 2Inspect the solenoid connector for oil and corrosion.
- 3Measure solenoid resistance (often 6–13 Ω) and compare with specification.
- 4Check for battery voltage and the ECU control signal at the connector.
- 5Check for technical service bulletins (TSBs) or software updates for your make and model; some codes have known factory fixes.
Common fixes
- Replace the VVT solenoid
- Repair the wiring or connector
This information is general guidance for all makes. Exact causes, specifications and procedures vary by vehicle, so confirm with your service manual or a qualified mechanic before replacing parts.