Idle Control System Malfunction
Table of contents
P0505 SCION Possible Causes
- Idle Air Control (IAC) Valve is stuck or closed
- Faulty Idle Air Control Valve
- Idle Air Control Valve harness is open or shorted
- Idle Air Control Valve circuit poor electrical connection
- Air Induction System (Intake leak)
- PCV hose connection
- Faulty Engine Control Module (ECM)
How do I fix code P0505 SCION?
Check the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector’s pins.
Cost of diagnosing the P0505 SCION code
The cost of diagnosing the P0505 SCION code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle’s make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.
Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Engine hard to start
- Rough or erratic idle speed
P0505 SCION Description
The rotary solenoid type Idle Air Control (IAC) valve is located on the throttle body and intake air bypassing the throttle valve is directed to the IAC valve through a passage. In this way the intake air volume bypassing the throttle valve is regulated, controlling the engine speed. The Engine Control Module (ECM) operates only the IAC valve to perform idle-up and provide feedback for the target idling speed.
The ECM regulates the idle speed by opening and closing the throttle valve using the ETCS. The ECM concludes that the idle speed control ECM function is malfunctioning and set the Diagnostic Trouble Code (DTC) if:
1. The actual idle RPM varies more than the specified amount five times or more during a drive cycle
2. The learning value of the idle speed control remains at the maximum or minimum five times or more during a drive cycle.
Example: If the actual idle RPM varies from the target idle RPM by more than 200* rpm five times during a drive cycle, the ECM will turn on the MIL and will set a DTC.