Skip the auto shop - Our mechanics make house calls

P0233 OBD-II Trouble Code: Fuel Pump Secondary Circuit Intermittent

Check Engine Light

P0233 code definition

Fuel pump Secondary Circuit Intermittent

What the P0233 code means

P0233 is a generic OBD-II code that is triggered when the engine control module (ECM) detects that the secondary circuit to the fuel pump has an intermittent voltage when the fuel pump relay is turned on.

What causes the P0233 code?

  • The engine control module (ECM) detects low, or no voltage to the secondary fuel pump circuit when the fuel pump relay is turned on

  • The fuel pump relay may have a poor or intermittent contact internally on the secondary side of the relay

  • The inertia fuel shutoff switch (IFS) is not passing voltage through it intermittently to the pump

What are the symptoms of the P0233 code?

  • The Check Engine Light will be illuminated and the P0233 code set

  • The engine will not start from lack of fuel pump operation whenever the problem is occurring

  • The engine may run normally until the problem occurs, then it will lose power and the engine will stall

How does a mechanic diagnose the P0233 code?

  • Scans codes and documents the freeze frame data in order to verify the problem

  • Clears the DTC codes to verify whether the concern comes back

  • Checks the IFS connection for any loose or corroded pins

  • Checks the fuel pump feed fuse or fusible link to see if it has a good contact to vehicle power

  • Tests to see if voltage is getting to the fuel pump secondary circuit through the IFS and relay while wiggling connections and wiring for intermittent connections

  • Lightly taps on relay and IFS to see if connection is lost to power the secondary fuel pump supply voltage

Common mistakes when diagnosing the P0233 code

Follow these simple guidelines to prevent misdiagnosis:

  • Verify that the battery voltage is not low and connections are good, causing intermittent voltage drops in the electrical system

  • Check the electrical connections at the fuel pump relay and at the IFS for any loose connections on the secondary side

How serious is the P0233 code?

  • The fuel pump secondary circuit powers the fuel pump and can cause a no start or the engine to suddenly stall while driving

  • A low battery voltage can trigger the code if the voltage falls below a specified level

What repairs can fix the P0233 code?

  • Replacing the fuel pump relay if it is making intermittent connection on the secondary side of the relay

  • Replacing the IFS or relay if it shows signs of corrosion inside the connections, and cleaning or replacing the connector of all corrosion

  • Repairing a low battery voltage condition by replacing the battery, or repairing and cleaning the connections

Additional comments for consideration regarding the P0233 code

Code P0233 is triggered when the ECM detects intermittent low voltage in the secondary circuit to the fuel pump through the relay falling below a specified voltage. Some vehicles have an IFS and use a relay, so check both of these on those vehicles.

Need help with a P0233 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

Post a question and get free advice from our certified mechanics.

ASK A QUESTION

More related articles

P0291OBD-II Trouble Code: Cylinder 11 Injector Circuit Low
P0291 code definition When your vehicle’s PCM registers the P0291 code, it means that a voltage reading came from the fuel injector circuit – for cylinder number 11’s fuel injector –...
P0359 OBD-II Trouble Code: Ignition Coil I Primary/Secondary Circuit Malfunction
P0359 code definition The P0359 code indicates that a fault has been detected in one of the vehicle’s ignition coils, generally the number 9 coil. This code can also be associated...
P0608 OBD-II Trouble Code: Control Module VSS Output "A" Malfunction
P0608 means there is an malfunction in the vehicle speed sensor A control module often due too faulty speed sensor or shorted electrical wiring.


Related questions

Q: Car bogging down

This may be related to a few different things such as a bad injector, fuel pressure issue, or potentially a faulty mass air flow sensor. A common symptom of a bad mass air flow sensor is very similar to what...

Q: P0786 code ford glaxay, gear shifting jurk or slip

This is a common code related to the MAP sensor. This can happen for a variety of reasons such as something as simple as a dirty mass air flow sensor which could be causing inaccurate fuel trim adjustments to be...

Q: Engine making weird noises and revving

With these combination of symptoms, it sounds like your car has a drive belt problem. When it is cold outside, there is more load on the belt on initial startup. In other words, the pulleys are harder to turn. When...