2000 Ford Mustang Fuel Pump Fuse: Location, Diagnosis, and Replacement Guide

If your 2000 Ford Mustang cranks but refuses to start, or if it stalls unexpectedly while driving, the fuel pump fuse is one of the first things you should check. The fuel pump fuse on a 2000 Ford Mustang is a 20-amp mini fuse located in the engine compartment fuse box (Power Distribution Box), specifically in position #14. Understanding where this fuse is, how to test it, and what to do when it blows can save you time, money, and the frustration of a stranded vehicle.

Understanding the Fuel Pump Circuit on Your 2000 Mustang

The 2000 Ford Mustang came with two main engine options: the 3.8L V6 and the 4.6L V8. While the engine configurations differ, the fuel pump electrical system is largely the same across both models. The system uses a returnless fuel delivery design, which means the fuel pump runs at a constant speed and pressure is regulated by a pressure sensor rather than a return line to the tank.

The fuel pump circuit consists of several key components:

  1. The Fuel Pump Fuse – A 20-amp mini fuse that protects the entire fuel pump circuit from overcurrent damage.
  2. The Fuel Pump Relay – Located in the engine compartment fuse box, this relay controls when power is sent to the fuel pump.
  3. The Fuel Pump Driver Module (FPDM) – This module is mounted in the trunk on the left side, behind the trunk liner. It regulates voltage to the fuel pump.
  4. The Inertia Fuel Shutoff Switch – Located in the trunk on the driver's side near the taillight, this switch cuts power to the fuel pump in the event of a collision.

Where Is the Fuel Pump Fuse Located?

The fuel pump fuse is located in the engine compartment fuse box, also called the Power Distribution Box (PDB). This black plastic box is typically found near the battery on the driver's side of the engine bay.

To access the fuse:

  1. Open the hood and secure it properly.
  2. Locate the fuse box – it's a rectangular black box with a removable lid.
  3. Remove the lid by pressing the retaining clips.
  4. Look at the diagram on the underside of the lid. Find position #14, which is labeled "Fuel Pump."
  5. The fuse is a 20-amp mini fuse and should be clearly identifiable.

Important note: Some earlier guides may mention a fuse under the dashboard for 1999-2000 models, but the factory service manual and most reliable sources confirm that the under-hood fuse box position #14 is the correct location for the fuel pump fuse on the 2000 Mustang.

How to Check the Fuel Pump Fuse

Before replacing any parts, it's wise to check the fuse first. Here's a simple step-by-step process:

Step 1: Visual Inspection
Remove the fuse using a fuse puller (often found inside the fuse box lid) or a pair of needle-nose pliers. Hold the fuse up to the light. Look through the clear plastic at the metal strip inside. If the strip is broken or melted, the fuse is blown.

Step 2: Use a Test Light or Multimeter
For a more reliable check, use a test light or multimeter:

  • Turn the ignition key to the "ON" position (do not start the engine).
  • Touch one probe to each of the two small metal prongs on top of the fuse (while it's still installed).
  • If the test light illuminates on both prongs, the fuse is good. If it lights on only one side, the fuse is blown.

What to Do When the Fuel Pump Fuse Blows

If you find that the fuel pump fuse is blown, simply replacing it may not solve the problem. A blown fuse is usually a symptom of a deeper electrical issue. Here's a systematic approach to diagnosing and fixing the cause:

1. Replace the Fuse and Test
Start by replacing the 20-amp mini fuse with a new one of the same amperage rating. Never use a higher-rated fuse, as this can cause wiring damage or fire. Try starting the engine. If the car starts and runs, the problem was likely a temporary surge or an old fuse that failed.

2. Check the Fuel Pump Driver Module (FPDM)
If the new fuse blows immediately, the FPDM is a common culprit. The FPDM is located in the trunk on the left side, behind the trunk liner.

  • Disconnect the wiring connector from the FPDM.
  • Replace the blown fuse with a new one.
  • Try to start the engine. The car won't start, but what you're checking is whether the fuse blows again.
  • If the fuse does NOT blow with the FPDM disconnected, the FPDM itself is likely faulty and needs replacement.

3. Inspect the Wiring Harness
If the fuse still blows with the FPDM disconnected, there may be a short in the wiring harness. Common causes include:

  • Rub-through wiring near the fuel tank or along the frame rails.
  • Damaged wiring from road debris or corrosion.
  • A shorted oxygen sensor that is affecting the fuel pump circuit.

4. Check the Fuel Pump Itself
If the FPDM and wiring check out, the fuel pump inside the tank may be failing and drawing excessive current. This can cause the fuse to blow intermittently. A failing fuel pump often produces symptoms like:

  • Whining noise from the rear of the car.
  • Hard starting, especially when the fuel level is low.
  • Loss of power under load or while accelerating.

5. Verify the Inertia Switch
The inertia switch in the trunk can also cause a no-start condition. If the red button on top of the switch is popped up, press it down to reset it. However, this switch does not typically cause a blown fuse.

Common Symptoms of a Blown Fuel Pump Fuse

Knowing the signs can help you diagnose the problem quickly:

  • Engine cranks but won't start – This is the most common symptom. The starter turns the engine over, but there's no fuel pressure.
  • No fuel pump prime noise – When you turn the key to the "ON" position, you should hear a brief humming sound from the rear of the car (the fuel pump priming). If you don't hear this, the fuel pump fuse or relay may be blown.
  • Sudden stalling while driving – If the fuse blows while you're driving, the engine will stall immediately and won't restart.
  • Fuel pump runs continuously – In rare cases, a stuck relay can cause the pump to run even with the key off, which may blow the fuse.

Relays and Other Components to Know

While the fuse is your first check, the fuel pump relay is also critical. On the 2000 Mustang, the fuel pump relay is located inside the engine compartment fuse box. It's typically labeled as part of the Constant Control Relay Module (CCRM) on V6 models, or as a standalone relay on V8 models.

The relay is a small, rectangular component that clicks when engaged. If the fuse is good but the fuel pump isn't running, the relay may be faulty. You can test the relay by swapping it with an identical relay in the fuse box (like the horn relay) and seeing if the fuel pump starts working.

Safety Precautions When Working on the Fuel System

Working with the fuel system requires caution. Always follow these safety guidelines:

  • Disconnect the battery before working on any electrical components.
  • Relieve fuel system pressure before disconnecting any fuel lines. The 2000 Mustang's fuel system holds pressure even when the engine is off.
  • Work in a well-ventilated area to avoid fuel vapor buildup.
  • Keep a fire extinguisher nearby rated for Class B (flammable liquids) fires.
  • Never use a fuse with a higher amperage rating than specified.

Preventive Maintenance Tips

To avoid future fuel pump fuse issues, consider these simple maintenance steps:

  1. Keep the fuel tank above a quarter tank – Running the tank low repeatedly can cause the fuel pump to overheat, leading to increased current draw and blown fuses.
  2. Use quality fuel – Contaminated fuel can clog the fuel filter and strain the pump.
  3. Replace the fuel filter regularly – A clogged filter forces the pump to work harder, drawing more current.
  4. Inspect wiring periodically – Look for any signs of wear or corrosion on the fuel pump wiring harness, especially near the rear axle and fuel tank.

Upgrade Your Fuel System with KEMSO

If you're dealing with a failing fuel pump or simply want to ensure your 2000 Mustang runs at its best, consider upgrading to a high-quality replacement. KEMSO Racing offers high-performance, OEM replacement fuel pumps designed to meet or exceed factory specifications. Their fuel pump products are built with durability in mind, featuring lifetime warranty coverage for your peace of mind. Whether you need a direct replacement for your stock V6 or V8 Mustang, or you're looking for improved flow for a modified engine, KEMSO has the right solution.

Visit https://www.kemsoracing.com/ to explore their full line of fuel pump products and other performance parts for your Ford Mustang.

Final Thoughts

The fuel pump fuse on your 2000 Ford Mustang is a simple component that can cause major headaches when it fails. By knowing its location (position #14 in the engine compartment fuse box, 20-amp mini fuse) and understanding how to diagnose the underlying cause of a blown fuse, you can save significant time and money.

Remember that a blown fuse is rarely the end of the story. Faulty Fuel Pump Driver Modules, damaged wiring, and failing fuel pumps are common root causes. Systematic troubleshooting will help you identify the real problem quickly.

If you need a reliable replacement fuel pump, consider KEMSO Racing for high-quality, OEM-replacement products backed by a lifetime warranty. Their fuel pumps are designed to deliver reliable performance for years to come. Check out their selection at https://www.kemsoracing.com/.

For more detailed information on your specific Mustang's electrical system, always refer to the owner's manual or a factory service manual. The 2000 Ford Mustang owner's manual provides a complete fuse box diagram and can be found online or in print.


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