Honda Accord Fuel Pump Relay Location: Your Essential Step-by-Step Guide

The fuel pump relay on a Honda Accord is always located inside the under-hood fuse and relay box, typically near the battery. Locating it is the crucial first step in diagnosing fuel pump electrical problems like a car that cranks but won't start. Understanding its exact position within that box and how to access and test it will save you time and money.

The starter spins the engine, but it refuses to catch and run. You don't hear the faint humming sound from the rear seat area that signals the fuel pump priming when you turn the key to the "ON" position before starting. These are classic symptoms pointing towards a potential issue with the fuel delivery system, and a primary suspect is often the fuel pump relay. Understanding its location is the vital starting point for diagnosis or replacement.

Why the Fuel Pump Relay Matters

Think of the relay as an electrical switch controlled by the main computer. When you turn the key (or press the start button), the Powertrain Control Module (PCM) sends a small electrical signal to the fuel pump relay. The relay responds by closing a much larger electrical circuit, allowing significant battery power to flow directly to the fuel pump located inside the fuel tank. Without the relay doing its job, the pump doesn't activate, no fuel gets pumped to the engine, and the car cannot start, regardless of how healthy the starter battery or the pump itself might be. The fuel pump relay location is your gateway to checking this critical component.

Uniform Location: The Under-Hood Fuse & Relay Box

Despite various generations and models of the Honda Accord spanning decades, the fuel pump relay location remains consistently within the under-hood fuse and relay box. This is the primary electrical center for the engine compartment, conveniently positioned near the vehicle's battery for easy power access. You won't find the fuel pump relay inside the car under the dashboard or hidden within trim panels; it resides exclusively under the hood. Here's what to look for:

  1. Pop the Hood: Release the hood latch inside the car, then go outside, lift the hood slightly, find the secondary release lever underneath the front center edge of the hood, and fully raise it. Secure it with the prop rod.
  2. Identify the Under-Hood Box: Walk to the side of the car where the battery is installed (usually the front passenger side for most Accords). Directly next to the battery, sometimes tucked behind it slightly towards the front fender, you'll see a rectangular, usually black plastic box with a lid. This is the under-hood fuse and relay box.
  3. Open the Box Lid: The lid is held down by simple latches, clips, or sometimes small bolts requiring a screwdriver. Gently press, slide, or unclip these mechanisms. Lift the lid straight up and move it aside where it won't get damaged or interfere. You'll now see an array of fuses (small plastic squares with metal prongs) and several larger plastic cubes – these cubes are the relays.

Finding the Specific Fuel Pump Relay Inside the Box

You now know the fuel pump relay location is inside this box. However, this box contains multiple relays that look virtually identical in shape and size. Identifying the correct one amidst several others is the next critical step. Don't rely on guessing; consult the labeling system Honda provides:

  1. Inspect the Box Lid: The inside surface of the lid you just removed is the primary map. Honda meticulously prints a comprehensive fuse and relay layout diagram directly onto it. This diagram lists each fuse and relay slot numerically or alphanumerically and identifies its function.
  2. Search the Diagram: Carefully scan this diagram for labels such as:
    • "Fuel Pump"
    • "FP" (common shorthand)
    • "PGM-FI Main" (Programmed Fuel Injection Main Relay - often incorporates the fuel pump relay function - Crucially important!)
    • "Main Relay" (Less common specific term, but sometimes still used).
  3. Locate the Slot Position: Find the corresponding number or letter on the diagram for the fuel pump relay location. Trace this position visually onto the physical fuse box layout beneath the lid. Note its position relative to easily identifiable markers like the power posts or a large fuse.
  4. Identify the Relay Physically: Go back to the open fuse box. Find the relay in the exact position indicated by the diagram. Most relays in this box will be standardized 4-pin or 5-pin mini ISO cube relays. The fuel pump relay is typically a standard mini-ISO cube relay, sharing the same form factor as other control relays nearby. Don't be surprised if it shares similar markings with other relays. Always confirm the position based on the diagram.
  5. Understand the PGM-FI Main Relay: On many Honda Accords (especially popular models like the 5th-10th generations), Honda combines the functions of the primary engine control relay and the fuel pump relay into a single, slightly larger component often called the PGM-FI Main Relay. It is frequently found in a prominent location within the under-hood box, sometimes denoted by a white base or white printing. If your diagram points to "PGM-FI Main," this is the relay that controls power to your fuel pump and numerous essential Engine Control Unit (ECU) functions. Its failure causes a no-start/no-pump scenario.

Double-Checking Your Identification

Before pulling anything out, take a final moment to verify:

  • Diagram Matches Slot: Is the relay you're looking at exactly in the position labeled "Fuel Pump," "FP," or "PGM-FI Main"?
  • Part Number (Optional but Helpful): If easily visible, the relay casing might have a Honda part number printed. Common numbers for the PGM-FI Main relay include 39400-Sxx-xxx variants (the "xx" varies by year/model). However, relying solely on visual relay identification without the diagram can be risky, as appearance can change slightly over production years, and non-OEM replacements may look different. The diagram position is the definitive guide for the fuel pump relay location.

Accessing and Removing the Relay

Once confidently identified based on the diagram position, removal is straightforward:

  1. Grip Firmly: Place your fingers securely around the body of the relay. Avoid pulling by the thin wires connected underneath (you can't even access them until the relay is out).
  2. Pull Straight Up: Relays plug directly downward into sockets. Apply steady, vertical upward pressure directly over the relay body. It should pull free of its socket with moderate force. There are no levers or twists involved – just a straight pull.
  3. Inspect: Examine the metal pins underneath the relay. Check if they look clean, straight, and free of significant corrosion or green/white crust (oxidation). Dirty pins can impede connection. Compare its appearance to other identical-looking relays nearby if you need reassurance it's different. However, remember its position is your key identifier.

Reinstalling or Replacing the Relay

Installation is the reverse of removal:

  1. Align Pins: Position the relay directly above its socket, ensuring the orientation is correct (the pins will only fit one way due to their arrangement).
  2. Press Firmly Down: Push the relay straight down vertically until it seats completely. You should feel and possibly hear a distinct click or snap as it locks into place. Don't force it; ensure pin alignment is correct first.
  3. Test Operation: If replacing a suspected bad relay, immediately test your result. Turn the ignition key to the "ON" position (don't start). Stand near the rear of the car, preferably by the fuel filler area or open a rear door, and listen carefully. You should hear the fuel pump activate for about 2 seconds, producing a distinct whirring or buzzing sound. Hearing this prime signals the relay is supplying power correctly.

Troubleshooting Tips When the Relay is Located

Locating the fuel pump relay location is essential, but what if testing or replacing it doesn't solve the problem? Knowing its location aids in deeper diagnostics:

  1. Swap Test (If Possible): If your box contains another relay identical in size, pin configuration, and labeled function (e.g., another PGM-FI Main is unlikely, but perhaps a horn relay or headlight relay shares the same mini-ISO standard type), you can temporarily swap it with the suspected fuel pump relay. Turn the key to "ON." If the fuel pump now primes, your original relay is faulty. If the horn (or other swapped function) stops working and the pump still doesn't prime, the issue likely lies elsewhere. Use this method cautiously, only with verified compatible relays, and return them to original positions afterwards.
  2. Electrical Testing: Accessing the relay socket allows for more advanced checks using a multimeter.
    • Ground Check: Verify one pin in the socket has good continuity to the vehicle chassis (negative battery terminal) using the multimeter's Ohms setting. Expect low resistance (near 0 Ohms).
    • Ignition Power: With the ignition turned to "ON," another socket pin should read full system voltage (12-13V) relative to ground.
    • Pump Power Output: With the ignition turned to "ON" (pump should prime), the designated output pin leading to the pump (usually different from the power input pin) should also show full voltage briefly. (Consult vehicle-specific wiring diagrams or use process of elimination carefully).
    • Control Signal: The small pin receiving the signal from the PCM should also see voltage briefly during prime when the ignition is turned on. A multimeter is highly recommended for these checks if swapping proves inconclusive.
  3. Check Fuses: While the fuel pump relay location is clear, the fuel pump power circuit is also protected by a fuse. Locate the fuse diagram inside the under-hood box lid. Identify the fuse labeled "Fuel Pump," "FP," or part of the PGM-FI circuit. Remove it visually or with fuse pullers (often included in the box lid). Look for a broken metal strip inside the clear plastic body. Replace with an identical amperage fuse if blown. Always check the fuse associated with the relay circuit.
  4. Beyond the Relay: If power reaches the fuel pump wire harness connection (near or on top of the fuel tank, accessible typically from inside the trunk or under the rear seat) when the key is in "ON," but the pump doesn't run, the fault likely is the pump itself. If no power reaches the harness connection, backtrack to the relay socket outputs and inspect wiring for damage.

Generational Notes on Honda Accord Fuel Pump Relay Location

While consistently located under the hood near the battery, the specific designation within that box can vary slightly across Accord generations. Here's a quick guide:

  • 5th Generation (1994-1997): Typically uses a PGM-FI Main Relay (often a slightly larger relay). Check the lid diagram for "PGM-FI Main" or "Main Relay."
  • 6th Generation (1998-2002): Almost universally uses the PGM-FI Main Relay. Frequently located near the front of the fuse box or against a sidewall.
  • 7th Generation (2003-2007): Primarily uses the PGM-FI Main Relay. Refer to lid diagram. Sometimes labeled clearly as a multi-function unit.
  • 8th Generation (2008-2012): Continues with the PGM-FI Main Relay tradition. Diagram is essential for slot ID.
  • 9th Generation (2013-2017): Still relies on the PGM-FI Main Relay integrated unit.
  • 10th Generation (2018-2022): The PGM-FI Main Relay remains standard. Diagram is crucial.
  • 11th Generation (2023-Present): Under-hood location remains consistent. Consult lid diagram for exact relay.

Regardless of generation, always, always rely on the fuse box lid diagram for the definitive fuel pump relay location and its correct label (FP, PGM-FI Main, etc.) for your specific vehicle.

Conclusion: Empowered Diagnosis Starts Here

Knowing the precise fuel pump relay location in your Honda Accord – always within the under-hood fuse box near the battery, definitively identified by the diagram on the box lid – is an invaluable piece of knowledge. It empowers you to efficiently tackle one of the most common causes of a frustrating no-start situation: a failed fuel pump relay or its integrated form within the PGM-FI Main relay. By following the steps to locate, identify, remove, test, and potentially replace this relay, you can often restore your Accord's ability to start and run properly without an expensive trip to the repair shop. Remember the sequence: Locate the under-hood box, open it, consult the lid diagram meticulously, find the relay based on position, test safely (swap or multimeter), check associated fuses, and move forward with confidence. Your journey to fixing a no-start problem begins with knowing exactly where this critical electrical switch lives.

Back to blog