P264B code meaning
"A" Rocker Arm Actuator Position Sensor Circuit Range/Performance (Bank 1)
Powertrain system Generic code P26xx codes Check engine light
What P264B means
Range/Performance means the bank 1 feedback sensor for actuator A delivers a signal inside its electrical limits that still does not fit what the engine expects, for example a position that lags or overshoots the commanded one, or that fails to move when the actuator is driven. CARB requires valve lift systems to catch target errors and slow response before emissions exceed set limits. No manufacturer documents P264B publicly; the closest documented case is Toyota's P265B on Valvematic engines (2014 Corolla, 2018–19 C-HR, 2020 Corolla), cured by ECM reprogramming or a new continuously variable lift controller. Worn linkage, a loose sensor, or a dragging actuator are plausible causes.
P264B at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor0.5 to 4 hours
- Clears after repairAfter a drive cycle
Symptoms of P264B
- MIL on after a drive cycle
- Hesitation or uneven power delivery
- Idle speed fluctuating
Common causes of P264B
- PossibleActuator or linkage moving sluggishly
- PossibleSensor loose or misaligned on its mount
- Less likelyControl software needing an update
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Rocker arm position sensor a b1Actuator mechanism
What each part of P264B means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 6 | Area: computer (engine control module) and output circuits. |
| 4B | The exact fault in that area. |
What to do next
- Note P264B and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P264B
What does P264B mean?
P264B means ""A" Rocker Arm Actuator Position Sensor Circuit Range/Performance (Bank 1)". Range/Performance means the bank 1 feedback sensor for actuator A delivers a signal inside its electrical limits that still does not fit what the engine expects, for example a position that lags or overshoots the commanded one, or that fails to move when the actuator is driven. It is a generic code, so it means the same on every make.
Is it safe to drive with P264B?
Drive gently and only to a workshop. With P264B the car can go into limp mode (reduced power) to protect itself.
Will P264B fail an emissions test?
Yes, it can. P264B is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P264B to fix?
Difficulty: hard. A typical repair takes 0.5 to 4 hours of work. This is a job for a workshop.
Will P264B clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.