Technical Description of OBD-II Trouble Code
The RPM of the Idle Air Control (IAC) System is Lower Than Expected
This diagnostic trouble code (DTC) is a generic powertrain code, which means that it applies to vehicles equipped with OBD-II. Although it is a generic code, the specific repair steps may vary depending on the make and model of the vehicle.
What does that mean?
This P0506 code is sometimes triggered in vehicles that have electronic throttle control, meaning they do not have a regular throttle cable connecting the accelerator pedal to the engine. Instead, they rely on sensors and electronics to control the throttle.
In this case, the P0506 DTC (diagnostic trouble code) is triggered when the powertrain control module (PCM) detects an engine idle speed that is lower than the desired (pre-programmed) RPM.
Potential Symptoms
The most noticeable symptom is a lower than normal idle speed, which may result in a rougher idle. There may also be other potential symptoms. Additionally, when trouble codes are set, the malfunction indicator lamp (MIL), also known as the check engine light, will illuminate.
Causes
A P0506 DTC trouble code may be caused by one or more of the following:
Possible Solutions
This DTC is more of an informational code, so if there are any other codes set, it is recommended to diagnose them first. If there are no other codes, inspect for vacuum leaks, restrictions, and damage. If there are no symptoms other than the DTC itself, simply clear the code and monitor whether it returns.
Other related DTCs: P0505, P0507
