Whenever an automatic transmission is replaced, overhauled or individual components are replaced, use this procedure to clear Engine Control Module (ECM, SAE term: Powertrain Control Module, PCM) “Learned Values” to minimize subsequent performance concerns. CAUTION: Failure to follow the procedure below may lengthen the time to readjust the ECM “Learned Values,” potentially resulting in performance concerns.
Applicable Vehicles
Refer to Reset Procedure 1 for the following vehicles with Electronically Controlled Automatic Transmissions:
Refer to Reset Procedure 2 for the following vehicles with Electronically Controlled Vehicles Automatic Transmissions:
Reset Procedure 1
1. Connect the Toyota Diagnostic Tester to the vehicle.
2. Reset the ECM (PCM). Refer to the procedures below.
3. Start the engine and warm it up to normal operating temperatures before test–driving.
4. Perform a thorough test drive with several accelerations from a stop with “light throttle” application until proper transmission shifting is verified.
Reset Procedure 2
1. Disconnect the negative battery cable for 5 minutes.
2. Reconnect battery cable.
3. Start the engine and warm it up to normal operating temperatures before test–driving.
4. Perform a thorough test drive with several accelerations from a stop with “light throttle” application until proper transmission shifting is verified.

Source

Related Tags: accelerations, automatic transmission, automatic transmissions, engine control module, engine control module ecm, failure, memory function, negative battery cable, performance concerns, powertrain, powertrain control module, scion, temperatures, test drive, throttle application, Toyota, toyota scion