Idle Air Control System Malfunction
Powertrain Code · Medium
What does P0505 mean?
The idle air control (IAC) system is not maintaining proper idle speed.
System: Idle Control
P0505 is a powertrain diagnostic trouble code indicating idle air control system malfunction. This code is classified as medium severity, which means: schedule service — affects performance or emissions. We have vehicle-specific diagnostic data for 43 models below. Select your vehicle for tailored causes, symptoms, and repair cost estimates.
Diagnostic data on this page is compiled from publicly available repair resources and technical service bulletins. Always have a qualified mechanic confirm the diagnosis before authorizing repairs on your vehicle.
See causes, symptoms, and repair costs for P0505 on specific vehicles: