The P0505 code on your 2022 Toyota RAV4 indicates a malfunction in the idle air control system. Modern vehicles with electronic throttle control (ETC) manage idle speed differently than older vehicles with traditional idle air control valves.
Modern Idle Control
The 2022 RAV4 uses electronic throttle control where the ECM directly controls the throttle plate for idle speed management. There's no separate IAC valve—the throttle body itself manages airflow at idle. P0505 indicates the system can't achieve or maintain proper idle speed.
What the ECM Monitors
The ECM targets a specific idle RPM based on engine temperature, load, and operating conditions. It adjusts throttle position to maintain this target. P0505 sets when the system can't achieve the target or the achieved idle doesn't match throttle position expectations.
Common Causes
Carbon buildup in the throttle body restricts airflow. Vacuum leaks cause unmetered air entry. A dirty or failing throttle body affects precise control. The throttle position sensor may be providing inaccurate feedback. Intake manifold leaks disrupt idle air management.
Diagnostic Approach
Use Toyota Techstream to monitor idle RPM targets and actual values. Check for vacuum leaks with smoke testing. Inspect the throttle body for carbon deposits. Monitor throttle position sensor readings for accuracy. Perform throttle body relearning after any cleaning or service.