DTC P0505: Idle Air Control System & DTC P0511: Idle Air Control Circuit: Notes
WARNING: This page is about a different car, the 2003 Toyota Tacoma. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
If Engine Control Module (ECM) replacement is instructed in following test, always ensure ECM connectors and ground circuits are okay. If either are defective, repair and repeat testing to confirm ECM malfunction.