P264A code meaning
"A" Rocker Arm Actuator Position Sensor Circuit (Bank 1)
Powertrain system Generic code P26xx codes Check engine light
What P264A means
Some valve lift systems report back where the rocker arm actuator actually is, rather than relying on oil pressure; continuously variable designs driven by an electric motor, such as Toyota Valvematic, work this way. P264A is the general circuit fault for the position sensor of actuator A on bank 1: signal missing or implausible without a clear low or high pattern. No manufacturer documents this code publicly with thresholds; Toyota's Valvematic bulletin T-SB-0098-19 files its sensor fault under the B sensor code P265B. CARB demands monitoring of all electrical parts of such systems. Without valid feedback the controller usually freezes lift at a safe value, costing power and fuel economy.
P264A at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor0.5 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P264A
- MIL on
- Lift held at a fixed value, less power
- Higher fuel consumption
Common causes of P264A
- Most likelyLoose or corroded position sensor connector
- PossibleDamaged signal, supply or ground wire
- PossiblePosition sensor failed internally
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 b1Wiring harness
What each part of P264A 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. |
| 4A | The exact fault in that area. |
What to do next
- Note P264A 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 P264A
What does P264A mean?
P264A means ""A" Rocker Arm Actuator Position Sensor Circuit (Bank 1)". Some valve lift systems report back where the rocker arm actuator actually is, rather than relying on oil pressure; continuously variable designs driven by an electric motor, such as Toyota Valvematic, work this way. It is a generic code, so it means the same on every make.
Is it safe to drive with P264A?
Drive gently and only to a workshop. With P264A the car can go into limp mode (reduced power) to protect itself.
Will P264A fail an emissions test?
Yes, it can. P264A 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 P264A to fix?
Difficulty: hard. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will P264A clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.