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P0414 OBD-II Trouble Code: Secondary Air Injection System Switching Valve A Circuit Shorted

Check Engine LIght

P0414 code definition

The P0414 code indicates that the car’s computer has detected an issue within the vehicle’s secondary air injection system. This system reduces emissions through ambient air being pumped into the exhaust.

What the P0414 code means

If your vehicle’s computer has stored the P0414 code, it means that there is an issue with the secondary air system. This system is used to pump air into the car’s exhaust in order to reduce emissions by accelerating catalyst operations. If there is a variation of more than 10% from the manufacturer’s specifications, the car’s PCM will note this and usually store the code. It is also possible that the Check Engine Light will turn on, although this is not the case in all instances, as some vehicles require more than one erroneous operation to set the code.

What causes the P0414 code?

There are a number of potential causes for the P0414 code, although it should be noted that this is code is seen more often in cold weather than in warm weather. Possible causes include the following:

  • A failed air pump
  • Open or short in the air bypass solenoid wiring harness
  • Corroded or damaged connection at the air bypass solenoid
  • A failed check valve in the air pump allowing moisture in, which freezes in cold weather
  • Cracked or damaged air injection hose

What are the symptoms of the P0414 code?

You will notice very few symptoms with the P0414 code. They include the following:

  • Check Engine light on
  • Engine hesitation
  • Unusual noise from the secondary air injection system
  • Engine stalling

How does a mechanic diagnose the P0414 code?

The first step in diagnosing the P0414 code is to connect an OBD II scanner to the car’s port (usually found under the dash on the driver’s side). The stored code or codes will be read, and then cleared. The technician will then test drive the vehicle to see if the code resets, as well as to duplicate any symptoms the driver mentioned.

The next step is to check the condition of the air injection hoses or lines (some cars use steel lines, while others use rubber hoses). Next, the technician will inspect the one-way check valves on the pump. If air moves both ways, then the valve is bad and must be replaced. In some instances, this is all that is needed. However, if sufficient moisture has entered the pump, replacing it as well may be necessary.

If the check valves test good, then the mechanic will need to check the wiring harness for signs of damage, as well as the connections for corrosion.

Common mistakes when diagnosing the P0414 code

One of the most common mistakes made here is assuming that the pump has failed and replacing it without checking the wiring harness for damage or the connections for corrosion. Because of its location, it is possible for the wiring harness to be burned by hot exhaust gases.

How serious is the P0414 code?

The P0414 code is very serious, as it will affect the drivability of your car, as well as your safety while on the road. One of the symptoms of this code is the possibility of the engine stalling while idling, which can leave you stuck in traffic. Have it diagnosed and repaired immediately.

What repairs can fix the P0414 code?

The repair needed will depend on the actual cause of the P0414 code. However, possible repairs include the following:

Additional comments for consideration regarding the P0414 code

It is crucial for mechanics to verify the condition of the one-way check valves before the pump, as replacing the pump but not the check valves in the lines will result in the new pump failing prematurely.

Need help with a P0414 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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