P0505: Idle Control System Malfunction
HighPowertrainIdle Control
What does P0505 mean?
P0505 is a diagnostic trouble code indicating "Idle Control System Malfunction". A component in the idle control has been flagged as malfunctioning by the vehicle's ECU. This requires diagnosis to determine whether the part itself has failed or if there is a related wiring or control issue.
Symptoms you may notice
- Check engine light (MIL) illuminated on dashboard
- Noticeable change in engine performance
- Unusual sounds or vibrations
- Possible issues with idle control operation
- Vehicle may enter reduced power mode (limp mode)
Estimated repair cost
Typical range in Australia (parts + labour)
$100 – $600 AUD
Common causes
- Faulty idle control component
- Wiring or connector issue in the related circuit
- Failed sensor providing incorrect readings
- Software/calibration issue requiring ECU update
- Related component causing secondary fault
What should you do?
This is a significant issue that should be diagnosed and repaired soon. Avoid long trips or heavy driving until the problem is resolved. Continued driving may cause additional damage.
Get a diagnosis for YOUR car
Code P0505 can mean different things depending on your vehicle. TorqueBot gives you a diagnosis specific to your make, model, and year.