P023F — Fuel Pump Secondary Circuit/Open #

Note: The label for DTC P023F may vary depending on the vehicle manufacturer (OEM). Below are some known variations:

• Fuel Pump Secondary Circuit/Open — Generic/SAE
• Fuel Pump “B” Control Circuit Open — Ford, GM
• Secondary Fuel Pump Circuit Malfunction — Chrysler

Summary of DTC P023F #

The P023F diagnostic trouble code (DTC) indicates a problem detected by the engine control module (ECM) or powertrain control module (PCM) in the secondary circuit of the fuel pump. The fuel pump is responsible for delivering pressurized fuel from the tank to the engine. In many vehicles, especially those with high-performance or turbocharged engines, a secondary (auxiliary) fuel pump or secondary circuit is used to provide additional fuel flow under certain conditions. An “open” circuit means the ECM/PCM is not detecting expected voltage or continuity, suggesting a break in the electrical path or a component failure. This can lead to reduced fuel delivery, engine performance issues, or even a no-start condition. Addressing this code promptly ensures optimum fuel system operation and avoids potential engine damage.

Common Symptoms for Code P023F #

When the P023F code is present, you’ll likely notice changes in your vehicle’s performance. The severity of symptoms can range from mild hesitation to severe drivability problems, depending on whether the secondary fuel pump circuit is intermittently failing or completely open. Here are the most common signs:

• Check Engine Light (CEL) illuminated
• Hard starting or failure to start, especially under load
• Engine misfire or hesitation during acceleration
• Reduced engine power or stalling
• Poor fuel economy
• Possible fuel pump noise changes

Most Likely Causes for P023F #

The root cause of a P023F code is most often an issue with the fuel pump’s secondary circuit, but the underlying reasons can vary. Here’s a breakdown of the most common causes, ranked by frequency:

1. Faulty fuel pump relay or fuse (secondary circuit)
2. Wiring issues — open, corroded, or damaged wires/connectors in the secondary fuel pump circuit
3. Defective secondary fuel pump
4. PCM/ECM malfunction or failed fuel pump driver module
5. Poor ground connection for the fuel pump circuit

Step-by-Step Diagnosis for Code P023F #

Diagnosing P023F requires a logical, stepwise approach to pinpoint the exact cause. The process typically involves both visual inspection and electrical testing. Here’s how a professional would approach this code:

• 1. Read and record all stored DTCs — Use a scan tool to note any related codes (especially fuel system or electrical codes).
• 2. Inspect the fuel pump relay and fuses — Verify that relays/fuses related to the secondary fuel pump circuit are functional.
• 3. Perform a visual inspection — Check wiring and connectors for signs of corrosion, damage, or loose connections, especially near the fuel pump and relay box.
• 4. Test for voltage and continuity — With a multimeter, check for battery voltage at the fuel pump connector and continuity between the relay, pump, and ECM/PCM.
• 5. Command the secondary fuel pump ON with a scan tool — Listen for pump operation and check for circuit response.
• 6. Check ground integrity — Measure and clean ground points associated with the fuel pump circuit.
• 7. Test or replace the secondary fuel pump — If all wiring and control circuit tests pass, the pump itself may be faulty.
• 8. Evaluate ECM/PCM function — As a last resort, consider module testing or reprogramming if all else checks out.

Possible Repairs for P023F #

Once the cause is identified, repairs should directly address the underlying issue. Here are the most common fixes for P023F, each linked to their respective cause:

• Replace faulty fuel pump relay or fuse — Quick, cost-effective, and often solves the problem.
• Repair or replace damaged wiring/connectors in the secondary circuit
• Replace defective secondary fuel pump
• Clean and secure all fuel pump ground connections
• Repair or replace a malfunctioning PCM/ECM or fuel pump driver module (only after confirming all other components are sound)

Is It Safe to Drive with Code P023F? #

Driving with P023F is not recommended. While some vehicles may experience only minor symptoms at first, a compromised secondary fuel pump circuit can quickly lead to unpredictable engine performance, stalling, or even a complete no-start condition. In the worst-case scenario, you could be left stranded. If you must drive, do so only for short distances and avoid heavy loads or high speeds until the issue is resolved.

Vehicles Most Commonly Affected by P023F #

This code appears most frequently on vehicles equipped with a secondary or auxiliary fuel pump circuit, particularly those with high-output or forced induction engines. Manufacturers using this system include:

• Ford (EcoBoost and Performance models)
• General Motors (Chevrolet, GMC, Cadillac performance models)
• Chrysler/Dodge/Jeep (SRT, Hellcat, and select RAM trucks)
• Certain BMW and Mercedes-Benz turbocharged models
• Other performance-oriented or fleet vehicles with dual fuel pump setups

Common Mistakes & Best Practices for P023F #

A misdiagnosis can waste time and money. Here’s what to watch out for, and how to get it right:

• Replacing the fuel pump without checking relays or wiring first
• Overlooking corroded or loose connectors, especially near the fuel tank
• Failing to test for proper voltage and ground at the pump
• Not scanning for related DTCs that could point to a root cause
• Skipping a detailed visual inspection before ordering parts

Quick FAQ for P023F #

Got more questions? Here are quick answers to the most common concerns about this code:

• Q: Does P023F always mean my fuel pump is bad?
  A: Not necessarily. Many times, the issue is a relay, fuse, or wiring problem. Always diagnose before replacing expensive components.
• Q: Can a DIYer fix this code?
  A: If you’re comfortable using a multimeter and following wiring diagrams, you can often identify and repair simple causes. For complex cases, professional help is recommended.