P2648
A Rocker Arm Actuator Control Circuit Low Bank 1
Voltage on the rocker arm actuator A control line on bank 1 is below the expected window. Usually a short to ground or a shorted solenoid coil.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: hard
Common causes
Ordered by how often each turns out to be the cause.
- Control wire shorted to groundCommon
- Internal short in solenoid coilPossible
- Connector pins corroded - high contact resistanceLess likely
Parts involved
- Rocker Arm Actuator A B1
- Oil Control Valve
- Wiring Harness
P2648 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.