P264B
A Rocker Arm Actuator Position Sensor Circuit Range/Performance Bank 1
The position sensor reading does not transition cleanly between the two valve lift modes on bank 1. Sensor drift or mechanical wear leaves the signal between expected values.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: hard
Common causes
Ordered by how often each turns out to be the cause.
- Sensor signal drift after thermal agingPossible
- Worn lock pin reduces travel between modesPossible
- Sensor element aged beyond calibration windowLess likely
Parts involved
- Rocker Arm Position Sensor A B1
- Actuator Mechanism
P264B 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.