P264D "A" Rocker Arm Actuator Position Sensor Circuit High (Bank 1)

With P264D the position signal of actuator A on bank 1 reads above its plausible maximum. An open ground return, a signal line touching the 5 V or battery feed, or water in the connector can push it up. Because a reading at the upper stop looks like an impossible position, the controller rejects it and runs a fixed lift. No public manufacturer documentation gives a threshold; the regulatory basis is CARB's demand to check every input of a variable lift system for out-of-range values. Toyota's Valvematic engines show that such feedback exists, though Toyota files its sensor faults under the B codes. Compare with P264C (low) and P264E (intermittent).

Likely causes

Symptoms

• MIL on
• Engine runs on a fixed lift setting
• Noticeably less power

Repair estimate

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

Related codes

References: law.cornell.edu, static.nhtsa.gov, en.wikipedia.org.