Tech notesCheck the ECM fuse, if fuse is OK try erasing the code first and if the code comes back you may have to reprogram or replaced the ECM.
There is a factory service bulletin for the following Toyota models:
2005 Toyota Corolla
2006 Toyota Corolla
2007 Toyota Corolla
2005 Toyota Matrix
2006 Toyota Matrix
2007 Toyota Matrix
2005-2007 Toyota Corolla, Matrix Factory Service Bulletin OBDII code P0606
When is the code detected?Indicates the ECM has experienced an internal memory fault.
P0606 Toyota DescriptionThe Engine Control Module (ECM) continuously monitors its internal memory status, internal circuits, and output signals to the throttle actuator. This self−check insures that the ECM is functioning properly. If any malfunction is detected, the ECM will set the code and illuminate the engine light.
The ECM memory status is diagnosed by internal mirroring of the main CPU and the sub CPU to detect Random Access Memory (RAM) errors. The two CPUs also perform continuous mutual monitoring. The ECM illuminates the MIL and sets a DTC if: 1) outputs from the two CPUs are different or deviate from the standards, 2) the signals sent to the throttle actuator deviate from the standards, 3) a malfunction is found in the throttle actuator supply voltage, and 4) any other ECM malfunction is found.