99 Honda Accord Fuel Pump Relay: Location, Testing, and Replacement Guide

The fuel pump relay on a 1999 Honda Accord is located in the under-dash fuse box on the driver's side, near the kick panel. If your Accord cranks but won't start, or you don't hear the fuel pump prime when you turn the key to the "ON" position, a faulty fuel pump relay is a common and inexpensive fix. This guide will walk you through finding it, testing it, and replacing it yourself.

Where Is the Fuel Pump Relay on a 1999 Honda Accord?

The fuel pump relay on a 1999 Honda Accord is housed in the under-dash fuse/relay box, which is on the driver's side, below the steering column. To access it, you need to remove the trim panel beneath the steering wheel. Once that panel is off, you will see the fuse box. The fuel pump relay is typically labeled "FP" or "FUEL PUMP" on the fuse box cover diagram. If you don't have the owner's manual, the diagram is often printed on the inside of the fuse box cover itself.

It's important to note that in some cases, the relay may be located in the engine compartment fuse box, but for the 1999 model, the under-dash location is the primary spot. Always cross-reference with the diagram on your fuse box cover.

Symptoms of a Bad Fuel Pump Relay

Before you start digging, here are the most common signs that your fuel pump relay is failing:

  1. Engine cranks but won't start: This is the most common symptom. The starter motor turns the engine over, but the fuel pump isn't getting power.
  2. No fuel pump priming sound: When you turn the ignition key to the "ON" position (without starting the engine), you should hear a faint whirring or buzzing sound from the rear of the car for about 1-2 seconds. This is the fuel pump priming. If you don't hear it, the relay may be bad.
  3. Engine stalls while driving: An intermittent failure can cause the relay to cut power to the fuel pump while the car is running, causing it to stall suddenly.
  4. Car starts after cooling down: If the relay is overheating internally, it may fail when hot but work again after the car sits for a while.

How to Test the Fuel Pump Relay

There are two simple ways to test the relay without needing expensive tools.

1. The Swap Test (Easiest Method)

This is the quickest diagnostic trick for DIYers.

  • Step 1: Locate the fuel pump relay in the under-dash fuse box.
  • Step 2: Find another relay in the same fuse box that is identical in size, shape, and part number. Common candidates include the horn relay, A/C clutch relay, or headlight relay.
  • Step 3: Carefully pull out the fuel pump relay and insert the known-good relay into its socket.
  • Step 4: Try to start the car. If the car now starts, your original fuel pump relay was faulty. If it still doesn't start, the problem is likely elsewhere.
  • Step 5: Remember to put the original relays back in their correct positions.

2. Visual and Auditory Check

  • Listen for the click: When you turn the key to "ON," you should hear a distinct "click" from the relay as it activates. If you hear nothing, the relay coil might be dead.
  • Visual inspection: Pull the relay out and look at the terminals. Are they corroded, bent, or burned? Look at the socket for any signs of melted plastic or damaged pins.

Replacing the Fuel Pump Relay

Once you've confirmed the relay is bad, replacement is straightforward. Safety first: disconnect the negative terminal of your car battery before starting.

Step-by-step replacement:

  1. Disconnect the battery: Use a 10mm wrench to disconnect the negative (-) terminal.
  2. Locate the relay: Find the faulty relay in the under-dash fuse box as described above.
  3. Remove the old relay: Grip the relay firmly and pull it straight upward. It may be snug, so a slight wiggling motion can help. Avoid yanking on the wires or using pliers that could damage the plastic housing.
  4. Inspect the socket: Check the socket for any signs of corrosion, rust, or damage. If you see damage, it may indicate a bigger electrical issue.
  5. Install the new relay: Align the pins of the new relay with the socket holes and push it firmly into place until it clicks or sits flush.
  6. Reconnect the battery: Reattach the negative terminal.
  7. Test the repair: Turn the key to "ON" and listen for the fuel pump priming sound, then start the engine.

Choosing the Right Replacement Part

Quality matters when replacing a fuel pump relay. You have two main options:

  • OEM (Original Equipment Manufacturer): This is the safest bet. Genuine Honda parts are designed specifically for your vehicle and are guaranteed to fit and function correctly. For a 1999 Accord, the OEM part number is typically 39794-SDA-004 or similar, but always verify with your VIN.
  • Reputable Aftermarket Brands: If you go aftermarket, choose a well-known brand. The part number for your 1999 Accord is often 39400-SM4-003 or 39400-SR3-003. Many aftermarket relays are compatible with multiple Honda models from 1990-2000, including the Accord, Civic, and CR-V. Avoid no-name, cheap parts, as they can fail quickly.

Recommended: KEMSO Fuel Pump for Your Honda Accord

For a reliable, long-lasting solution, consider upgrading to a KEMSO Fuel Pump. KEMSO is a brand known for producing high-performance, OEM Replacement fuel pumps. Their products are designed to meet or exceed the original factory specifications, ensuring a perfect fit and reliable operation for your 1999 Honda Accord.

Why choose KEMSO?

  • High Performance: Designed for optimal fuel delivery.
  • OEM Replacement: A direct fit, so installation is simple.
  • Lifetime Warranty: KEMSO stands behind the quality of their products, offering peace of mind.

To find the perfect fuel pump for your 1999 Honda Accord, visit their website: https://www.kemsoracing.com/ . Check their product catalog for compatibility with your specific engine and trim level.

Final Thoughts

A faulty fuel pump relay is a common and easily fixable problem on a 1999 Honda Accord. It's almost always located in the under-dash fuse box on the driver's side. Testing it with a simple swap test can save you time and money. When replacing, always choose a quality part. If you need a new fuel pump itself, KEMSO offers a great option with a lifetime warranty. For more information, visit https://www.kemsoracing.com/.


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