Skip the auto shop - Our mechanics make house calls
  1. Home
  2. Articles
  3. P2409 OBD-II Trouble Code: Fuel Cap Sensor/Switch Circuit Range/Performance

P2409 OBD-II Trouble Code: Fuel Cap Sensor/Switch Circuit Range/Performance

Check Engine Light

P2409 code definition

Fuel Cap Sensor/Switch Circuit Range/Performance

What the P2409 code means

P2409 is an OBD-II generic code for the Engine Control module (ECM) detecting the fuel cap sensor, switch or circuit is out of range or performance within the specifications.

What causes the P2409 code?

  • The ECM monitors the fuel cap to see if it is open or closed. The code is set when the fuel cap is left open or the circuit has failed open.

  • The Evaporative Emission Control System (EVAP) cannot operate correctly if the fuel cap is left open.

  • The fuel cap sensor is out of the specified range for a closed or open cap.

What are the symptoms of the P2409 code?

  • The Check Engine Light will be illuminated and the code is set in the ECM memory as a fault.

  • The vehicle will not run any different in most cases.

  • The vehicle may have a fuel odor in the vehicle or around the fuel cap.

  • The vehicle may have a Check Gas Cap Light on in the dash.

  • The vehicle will fail emission testing.

How does a mechanic diagnose the P2409 code?

  • Try to scan for codes and document the codes in the ECM memory and look at the freeze frame data for the problem before clearing the codes and retesting.

  • Check the fuel cap to see if it is loose or missing.

  • Test the resistance of the cap switch or sensor and check toward its specification.

  • Test wiring for open circuits between the ECM and the cap sensor.

Common mistakes when diagnosing the P2409 code?

  • Clearing ECM memory codes before checking the freeze frame data for the main failure problem, so the failure may be duplicated and repaired.

  • Failing to clear the ECM codes after the codes are fixed.

  • Failing to verify the failure before replacing parts.

  • Failing to check with the vehicle operator to see if the cap was recently left off or loose.

How serious is the P2409 code?

Code P2409 is an indication that the gas cap is not closed or not activating the cap closed switch or sensor. The cap being left off can cause fumes to build up around the vehicle. Dirt and water may be able to get in the tank and contaminate the fuel in the tank if the cap is off.

What repairs can fix the P2409 code?

  • Replace the gas cap if it is not closing properly or is missing.
  • Replace the gas cap closed sensor or switch.
  • Repair the wiring to the gas cap switch or sensor.

Additional comments for consideration regarding the P2409 code

Code P2409 is for the gas cap closed sensor or switch. The most common cause for this code is when the operator is not closing the cap tight enough every time and the sensor detects this as a performance problem with the sensor, thus turning on the light and setting the code.

Need help with a P2409 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
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

Veteran and Military Driver Laws and Benefits in New Mexico
The state of New Mexico offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch...
P2159 OBD-II Trouble Code: Vehicle Speed Sensor B Range/Performance
Diagnostic Trouble Code (DTC): P2159 P2159 code definition Vehicle Speed Sensor B Range/Performance...
Auto Safety Tips
Driving is more than a way to get from point A to point B. Owning and driving a car can also be a highly enjoyable experience. Whether a person is driving...

Related questions

Q: I get trouble code P2138, but I have cleared it and the car works for a while. Now I am getting trouble code P2127 along with P2138.

Hi there. The pedal position sensor on the gas pedal has lost signal for the switch 'E' and 'D'. The code P2138 means that the computer has discovered a malfunction with the pedal sensor. Check the harness to the...

Q: Check Engine code p0758

A P0758 code indicates a problem with the vehicle's shift solenoid, specifically shift solenoid B. If this light has come on, then the vehicle may be experiencing poor performance, or unusual shifting. As this component is located on the underside...

Q: Hello I have a 2006 f150 XLT with a 2v 4.6. It has a cold air intake from k

Hi, thanks for writing in. I'd be happy to help you. Code P2104 relates the throttle position control actuator, and code P2126 relates to the throttle position sensor. When either of these components is not working properly, this can cause...