Closed Throttle Position Learning Performance Problem - P1226 Code - General

Closed Throttle Position Learning Performance Problem

OBD-II code P1226 represents a problem with the closed throttle position learning performance of your vehicle.

The electronic throttle control actuator is made up of the throttle control motor, throttle position sensor, and other components in this system. The throttle position sensor, or TPS, is meant to respond to movement in the throttle valve.

Your vehicle's throttle position sensor has two sensors; these sensors transform the signals from the throttle valve position into voltage. The throttle position sensor then sends the voltage signals from the throttle valve position to the vehicle's engine control module or ECM. Additionally, these sensors monitor the opening and closing speeds of the throttle valve and sends those voltage signals to the engine control module. With this data, the ECM will then judge the current throttle valve opening angle and control the throttle motor for proper opening angles in response to driving conditions.

Possible causes of the P1226 code include:

  • Faulty electric throttle control actuator, throttle position sensor 2
  • Faulty throttle control actuator harness is open or shorted, throttle position sensor 2
  • Electric throttle control actuator circuit has a poor electrical connection, throttle position sensor 2

To nail down the exact cause of the code, do a visual inspection for loose wires and connections at the sensor, or damage to the sensor body itself. If no problems with the wiring and connections are detected, a worn/damaged electric throttle control actuator is likely at fault. Signs of a bad throttle control actuator include erratic acceleration, and unresponsive throttle, and poor fuel economy.

While we do make every effort to offer expert advice on this trouble code, you should consult with a professional before making any major repairs. This guide is meant to give you information about what causes the trouble code itself and is not meant to act as your only source for making repairs.

For a comprehensive list of trouble codes, check out this article on the Toyota Parts Center Blog.