How To Fix P0505 Obd2 Code?

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How To Fix P0505 Obd2 Code?
Table of Contents

The Idle Air Control Valve is critical to your vehicle’s engine. In situations where your car is stopped, but the engine is still running, this component is in charge of controlling the engine speed (RPM). AIC can increase or decrease engine RPM as necessary. Even though you may not even notice it, it’s performing its job.

An idle air control system problem will be flagged by your car’s primary computer, which is known as the powertrain control module (PCM). The PCM will also log the proper diagnostic trouble code. P0505 is one of the codes that may show up on the scanner.

Definition of P0505: P0505 code can be defined as the failure of the Idle Management System.

Meaning of P0505

The engine control module (ECM) decided that the engine idle control system is not managing the idle to stay in the specification, hence P0505 is an obd2 generic code. The idle is either too high or too low. The higher the idle, the more air the IAC gets around the throttle plate. With varying engine demands, the PCM assists in maintaining the optimum optimal speed.

Meaning of P0505

Depending on the model, there may be one or more wire sensors. The PCM also detects anomalies in the IAC circuits, and one or more of the IAC circuits will set the Error Code P0505 as soon as it detects the incorrect voltage. When the throttle is closed or at idling, problems with the IAC are usually only noticeable

Symptoms of P0505

There are a few possibilities that your car may be experiencing if you suspect you have a P0505 code. The Engine Light will turn on, and the code will be stored in the ECM memory. The engine’s idle speed may be lower or greater than the manufacturer’s standards. Following are the symptoms:

  • Check The engine light has come on.
  • To idle a stalling engine, a vigorous throttle squeeze is required.
  • When the throttle is taken off, the car stalls on occasion.
  • Low idle speed of the engine and engine death at stop signals
  • The idle speed that is too fast or too slow
  • When coming to a stop, the engine may stall.
  • At times, the engine’s idle may be too high.

Causes of P0505

The emergence of this problem and the subsequent appearance of the P0505 error code can be traced back to several different factors. The most prevalent culprit is a carbonized idle air control (IAC) valve. Carbon buildup might cause it to stick or have restricted maneuverability. Dirt, debris, or carbon buildup in the IAC passageways may potentially be at blame. Lastly, the engine may have a vacuum leak in its intake system. Either the throttle body, which the ECM cannot regulate using the IAC, or the accelerator pedal. P0505 is an obd2fault code that indicates that the PCM is keeping track of the voltages in the IAC circuits and that a problem has been found. Only at idle, with the throttle closed, and generally when the car is parked, would you detect an issue with the IAC.

  • IAC motor link has been damaged.
  • IAC circuits that are open or shorted to the ground.
  • It is shorted to the voltage of the IAC circuit.
  • IAC failure and a malfunctioning motor.
  • A noticeable accumulation of air passages in the throttle body
  • The buildup of carbon in the Throttle Body air channel.

How to diagnose P0505 Obd2 code

The P0505 code can only be fixed with an accurate diagnosis. Finding the source of the problem, on the other hand, may prove difficult in light of a large number of potential triggers for the error code. You can leave the diagnosis to a mechanic, or you can use a repair manual or an online tutorial to assist you to figure out what’s wrong. If you’d want to learn more about the P0505 code, you may watch the video below: Clears and verifies the code by scanning and documenting it in the ECM.

Checks to check if the engine idles remain within specifications in and out of gear and during a road test by monitoring the engine’s performance. The engine’s throttle plates and IAC valve inlet should be checked for carbon buildup. To see if the engine’s base idle is within specs, the IAC is disconnected. Remove the IAC and look for any obstructions to the flow of air.

A common mistake you must avoid when diagnosing p0505

Replacing the IAC without making sure the engine does not have a vacuum leak.

If replacing the IAC valve, do not remove excess carbon from the IAC passageways.

How to fix the p0505 Obd2 code

How to fix p0505

  • Clear any stored fault codes in the PCM to begin your P0505 diagnosis.
  • Check the IAC for carbon and oil buildups.
  • You should clean and reinstall the IAC if you find it to be clogged with debris. 
  • Start the engine and check for the return of the fault code P0505 when the IAC is attached. Keep going with this diagnosis if this issue code reappears.
  •  Start the car by unplugging the IAC. 
  • Other error codes will be generated as a result, but you can choose to disregard them for the time being.
  •  Replace the IAC if the error number P0505 does not display when the engine is started without the IAC connected. 
  • We advise checking the connections and harness. 
  • The PCM should be checked if the trouble code P0505 continues coming back even after you’ve eliminated all possible wiring issues. 
  • The IAC wires connecting the IAC and PCM should all be checked for continuity. 
  • The PCM likely is to blame if the P0505 code does not return after disconnecting the IAC wires from the PCM connector.
  •  Replacement of the PCM should only be considered as a last resort if the PCM is defective.

Tips for avoiding p0505 obd2 error

 P0505 is a diagnostic code for inconsistent idle and a lack of control over the idle speed. An intake or throttle body pressure line issue is the most frequent occurrence. Use this guide to help you identify, diagnose, and fix a P0505 problem. Diagnose the problem by following the procedures and avoiding the most typical blunders.