2004 Honda Accord Fuel Pump Relay Location: Find It, Test It, and Fix It Fast

If your 2004 Honda Accord cranks but won’t start, stalls while driving, or takes multiple tries to fire up, the fuel pump relay is likely the culprit. On the 2004 Honda Accord, the fuel pump relay is located inside the passenger compartment, specifically mounted behind the left side of the dashboard near the driver’s kick panel. This relay is part of the PGM-FI main relay assembly, which controls power to both the engine computer and the fuel pump. Before you assume the fuel pump itself has failed and start tearing into the tank, testing and replacing this relay is the faster, cheaper fix nine times out of ten. Relays fail far more often than fuel pumps, especially on Hondas from this era, and swapping it out takes about five minutes with no special tools required.

Where Exactly Is the Fuel Pump Relay on a 2004 Honda Accord?

The fuel pump relay on a 2004 Honda Accord is not under the hood. That catches a lot of people off guard. Instead, it’s in the interior fuse box on the driver’s side. On the 2004 model, the PGM-FI main relay is mounted to the left side of the steering column, tucked up above the hood release lever. It is secured to the metal bracket with a single 10mm bolt.

Here is how to access it:

  1. Open the driver’s door. You need access to the lower dash panel on the left side of the steering wheel.
  2. Remove the left kick panel. This is the plastic trim piece that covers the fuse box area. On the 2004 Accord, there is usually one Phillips-head screw at the bottom and a metal clip holding the top edge. Pull the panel straight off after removing the screw.
  3. Look above the hood release lever. The relay is a black or grey plastic box, larger than a standard mini-relay, with multiple wires running into it. It has seven wires in two rows on the connector. It is bolted directly to the bracket with a 10mm bolt.
  4. Remove the bolt and unplug the relay. Use a 10mm socket or wrench to remove the bolt. Then pull the relay straight out of its connector.

That is the entire process. No need to remove the glove box, no need to crawl under the dash on the passenger side. On the 2004 Accord, the main relay lives right there, in plain sight once you pull that kick panel off.

Why the 2004 Accord’s Fuel Pump Relay Fails

The fuel pump relay on the 2004 Honda Accord has a known weak spot: the solder joints inside the relay crack over time due to heat cycling and vibration. When these joints crack, the relay stops sending power to the fuel pump. The tricky part is that this failure is often temperature-sensitive. The relay will work fine when the car is cold, but after driving for a while and the engine bay heat soaks into the cabin, the cracked solder joint expands and loses contact. The engine stalls, then won’t restart until the relay cools down. This is why intermittent stalling followed by a no-start condition is the classic symptom of a failing main relay on the 7th generation Accord.

One owner of a 2004 Honda Accord V6 described exactly this scenario: the car stopped at a traffic light, would not restart for several tries, then eventually fired up, only to stall again after a few hundred meters. After the car sat for 15-20 minutes, it would start again, then stall again after less than a minute. That intermittent, temperature-dependent behavior is textbook fuel pump relay failure. The roadside assistant found no error codes in the computer because the relay failure does not always trigger a check engine light.

Symptoms of a Bad Fuel Pump Relay on the 2004 Accord

Recognizing these symptoms early can save you from being stranded. If your 2004 Honda Accord is showing any of the following, start with the relay:

  • Engine cranks but won’t start. This is the most common symptom. You turn the key, the starter spins the engine, but it never fires up.
  • No fuel pump prime sound. Turn the ignition key to the “ON” position (do not crank the engine). You should hear a faint humming sound from the rear of the car for about two seconds. That is the fuel pump pressurizing the system. If you do not hear it, the pump is not getting power. Listen near the fuel filler door or remove the gas cap and put your ear to the filler neck.
  • Intermittent stalling. The car runs fine for a while, then suddenly dies while driving. After sitting for 10-20 minutes, it starts again. This is the classic heat-related relay failure.
  • Long crank times. The engine cranks for several seconds before finally starting. This means the fuel pump is getting power only intermittently.
  • Car starts then immediately stalls. If the engine fires up for a second using residual fuel pressure, then dies, the relay is likely not keeping the pump running.

How to Test the Fuel Pump Relay on a 2004 Honda Accord

Before you buy a new relay, you can test the existing one. Testing is straightforward and requires only a multimeter.

Test 1: The Swap Test (Easiest Method)

This is the fastest way to diagnose a bad relay. Many relays in the under-hood fuse box on the 2004 Accord are identical to the fuel pump relay. Look for relays with the same part number and physical size. Common candidates include the horn relay or the rear defroster relay. Pull the suspect fuel pump relay out, and swap it with a relay you know works from a less critical system. If the car starts after the swap, the original relay was bad.

Test 2: Bench Test with a Multimeter

If you want a definitive answer, test the relay out of the car.

  1. Remove the relay. Pull it straight out from its connector.
  2. Identify the pins. Most automotive relays have four or five pins. The two smaller pins are the coil (control circuit). The two larger pins are the switch (power circuit).
  3. Check coil resistance. Set your multimeter to ohms (Ω). Connect the probes to the two smaller pins. You should see a reading between 50 and 150 ohms. If you get “OL” (open line) or infinite resistance, the coil is burnt out and the relay is dead.
  4. Test continuity on the switch side. Set the multimeter to continuity or ohms. Connect the probes to the two larger pins. You should get no continuity (infinite resistance) when the relay is unpowered.
  5. Apply power to the coil. Connect a 12V battery or power supply to the two smaller pins (polarity does not matter for most relays). You should hear an audible click. Now check the two larger pins again. You should get continuity (low resistance, usually less than 1 ohm). If you hear the click but still get no continuity, the internal contacts are burnt and the relay is bad.

What If the Relay Tests Good?

If the relay passes both tests and the car still won’t start, you need to dig deeper. The problem could be:

  • Blown fuel pump fuse. Check the under-hood fuse box for a fuse labeled “FUEL PUMP” or “PGM-FI.” A blown fuse will cut power to the pump entirely.
  • Bad fuel pump. If the relay and fuse are fine, the pump itself may have failed. On the 2004 Accord, the fuel pump is located inside the fuel tank, accessible through an access panel under the rear seat. You can test for 12V power at the fuel pump connector using a multimeter.
  • Wiring issues. Corroded or broken wires between the relay and the fuel pump can cause intermittent or total failure. Check the wiring harness under the car, especially near the fuel tank.
  • Failed PGM-FI main relay (the whole assembly). On the 2004 Accord, the fuel pump relay is part of the PGM-FI main relay assembly. If the relay itself is fine but the main relay board has a cracked solder joint, the entire assembly may need replacement. This is a known issue on 7th generation Accords.

Step-by-Step Replacement: How to Swap the Fuel Pump Relay on a 2004 Honda Accord

Replacing the relay is simple. Here is the process:

  1. Remove the left kick panel as described earlier.
  2. Locate the PGM-FI main relay. It is bolted to the bracket above the hood release.
  3. Remove the 10mm bolt holding the relay to the bracket.
  4. Unplug the relay connector. Pull it straight out. Do not yank on the wires.
  5. Plug in the new relay. Make sure it clicks firmly into place.
  6. Bolt the relay back onto the bracket. Do not overtighten.
  7. Reinstall the kick panel. Line up the metal clip at the top, then push the bottom in and reinstall the screw.
  8. Test the car. Turn the key to the “ON” position and listen for the fuel pump prime sound. Then start the engine.

The entire job takes about 10 minutes. The fuel pump relay part number for the 2004 Honda Accord is 39794-SDA-004. This is a genuine Honda OEM part used across many Honda and Acura models from 2003 onward. Check your owner’s manual or fuse box diagram to confirm, but this part number covers a huge range.

Common Mistakes People Make

Mistake 1: Replacing the fuel pump instead of the relay. This is the most expensive mistake. The symptoms of a bad relay and a bad fuel pump are nearly identical. Always test or swap the relay first. A new fuel pump costs hundreds of dollars and requires dropping the fuel tank or cutting an access panel. A new relay costs under $70 and takes minutes to install.

Mistake 2: Looking under the hood. The 2004 Honda Accord fuel pump relay is not in the under-hood fuse box. It is inside the car, behind the driver’s kick panel. Looking under the hood wastes time and causes confusion.

Mistake 3: Ignoring the intermittent symptoms. If your car stalls when hot but starts fine when cold, do not assume the problem will go away. It will get worse. The cracked solder joints in the relay degrade over time until the relay fails permanently.

Mistake 4: Not using a genuine replacement. Aftermarket relays may not match the pin configuration or electrical ratings of the OEM part. Stick with the genuine Honda part number 39794-SDA-004 or a high-quality equivalent from a trusted brand that provides OEM replacement specifications.

Final Thoughts

The 2004 Honda Accord fuel pump relay location is behind the driver’s side kick panel, above the hood release lever, secured with a 10mm bolt. If your Accord is having trouble starting or stalling intermittently, this relay should be the first thing you check. Testing it takes minutes with a multimeter or even less time with the swap test. Replacing it is one of the easiest and cheapest repairs you can do on this car. Do not fall into the trap of replacing the fuel pump before confirming the relay is good. That mistake costs hundreds of dollars and hours of labor. Start with the relay, and nine times out of ten, you will have your Accord back on the road in under an hour.

Why Choose KEMSO for Your Fuel Pump Replacement

If testing confirms that your fuel pump itself needs replacement, you want a part that delivers reliable performance without breaking the bank. That is where KEMSO comes in. KEMSO fuel pumps are built as high-performance, OEM replacement units that match or exceed the specifications of your factory equipment. Every KEMSO fuel pump comes with a lifetime warranty, giving you peace of mind long after the installation is done. Whether you drive a Honda Accord, a BMW motorcycle, a Kawasaki Jet Ski, or any other vehicle on the road, KEMSO has a direct-fit solution designed for durability and consistent fuel delivery. Skip the expensive dealer parts and the questionable used pumps. Choose a brand that stands behind its product with a lifetime guarantee. Visit https://www.kemsoracing.com/ to browse the full lineup of KEMSO fuel pumps and find the right fit for your 2004 Honda Accord or any other vehicle in your garage.

For more detailed guides, product updates, and DIY tips, check out the KEMSO blog and product pages at https://www.kemsoracing.com/.


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