1993 Honda Accord Fuel Pump Relay Location: Find It Fast & Fix Starting Problems

The fuel pump relay on a 1993 Honda Accord is located inside the underhood fuse and relay box, mounted near the driver's side strut tower. Specifically, it occupies position #6 within that box. Identifying and accessing this relay is crucial for diagnosing and resolving common no-start or fuel delivery issues with this vehicle.

Knowing where to find this critical component can save you time, money, and frustration when your Accord won't start. This guide provides detailed, step-by-step instructions to locate, identify, test, and replace the fuel pump relay in your 1993 Honda Accord.

Detailed Location of the 1993 Honda Accord Fuel Pump Relay

  1. Open the Hood: Ensure the vehicle is parked on a level surface with the parking brake engaged. Pull the hood release lever inside the cabin, then go to the front of the car, release the secondary safety latch under the hood's center front edge, and lift the hood securely.
  2. Locate the Underhood Fuse/Relay Box: Stand facing the front of the car. Look towards the rear of the engine compartment on the driver's side (left side for US-spec vehicles). You will see a rectangular black plastic box mounted vertically on the inner fender wall, close to the top of the suspension strut tower. This is the primary fuse and relay box.
  3. Open the Fuse/Relay Box: The box has a lid secured by clips. Press the clips inward or upward (depending on the specific design) and lift the cover off. Set the cover aside safely. Inside, you'll see an array of fuses (smaller, usually colored plastic) and larger cube-shaped relays.
  4. Identify Position #6: The relays and fuses are arranged in specific positions within the box. The positions are often numbered on the box itself, molded into the plastic near each slot, or indicated on a diagram printed on the underside of the cover you just removed. Carefully look for the position labeled "6".
  5. Recognize the Fuel Pump Relay: The relay in position #6 is the fuel pump relay. It's a standard automotive cube relay, typically black in color, measuring roughly 1 inch by 1 inch. It will have four or five metal blade terminals protruding from its bottom. Crucially, the relay itself or the socket it plugs into should be labeled. Common labels include:
    • FUEL PUMP
    • FP
    • PGM-FI (Honda often groups main relay and fuel pump relay functions, but position #6 is consistently the fuel pump relay in this box for the 1990-1993 Accord).
    • F/P
    • The diagram under the lid is your definitive guide – match position #6 to the label "Fuel Pump" or similar.

Visual Confirmation and Relay Identification

While position #6 is key, confirming the label is essential. Relays can look very similar. Here’s how to be sure:

  • Check the Lid Diagram: This is the most reliable method. The diagram clearly maps each numbered position to a specific circuit (e.g., Headlight, Cooling Fan, Horn, Fuel Pump).
  • Inspect the Relay Socket: Look closely at the plastic socket where the relay plugs in. Often, the function (FUEL PUMP, FP) is molded into the plastic next to the socket.
  • Inspect the Relay Body: Sometimes, the relay itself has a label on its top or side indicating its function. However, replacement relays might not, so relying on position and socket labeling is better.
  • Compare Relays (Use Caution): If you suspect a relay is faulty, you could carefully swap the relay from position #6 with an identical relay from another position known to be working correctly (like the horn relay, often position #5 – check your diagram first!). If the starting problem moves (e.g., horn stops working but car might start), it points to a faulty fuel pump relay. Only do this if you are confident and note the original positions!

Why the Fuel Pump Relay Matters

The fuel pump relay is an electromagnetic switch controlled by the engine control unit (ECU). Its job is critical:

  1. Safety: It prevents the fuel pump from running continuously when the engine is off or the key is just in the "ON" position.
  2. Power Control: When you turn the ignition key to the "START" position (and briefly in "ON" before cranking), the ECU sends a signal to energize the relay.
  3. Circuit Completion: The energized relay closes its internal contacts, completing the high-current circuit that delivers battery power directly to the fuel pump.
  4. Fuel Pressure: The fuel pump runs, pressurizing the fuel rail so the injectors can spray fuel when the engine cranks.

If this relay fails, power never reaches the fuel pump. No fuel pressure means no fuel delivery, resulting in a crank-but-no-start condition. It's a very common failure point on older Hondas.

Symptoms of a Faulty Fuel Pump Relay

A failing or failed fuel pump relay in your 1993 Accord often shows these signs:

  1. Engine Cranks But Won't Start: The most common symptom. The starter motor turns the engine over, but there's no fuel being delivered to start combustion.
  2. Intermittent Starting Problems: The car might start fine sometimes and fail to start other times. This can happen as the relay's internal contacts become worn or corroded, making inconsistent connections. Tapping the relay might temporarily get it working.
  3. No Fuel Pump Prime Sound: When you turn the ignition key to the "ON" position (before cranking), you should hear a distinct whirring or humming sound from the rear of the car (near the fuel tank) for about 2 seconds. This is the fuel pump priming the system. No prime sound is a strong indicator of either a failed fuel pump relay, a blown fuse, a wiring issue, or a failed pump itself. Checking the relay is the easiest first step.
  4. Relay Doesn't Click: With the key turned to "ON," you might hear a faint but audible click from the underhood fuse box as the fuel pump relay energizes. If you don't hear this click (and you know you should hear other relays click), it suggests the relay isn't activating. Note: Sometimes the click is very subtle.

How to Test the 1993 Accord Fuel Pump Relay

Before replacing the relay, it's wise to test it. You have a couple of options:

Method 1: The Swap Test (Simple but Requires Known Good Relay)

  1. Locate another relay in the underhood box that is identical in appearance and pin configuration to the suspected fuel pump relay (position #6). The horn relay (often position #5) is frequently the same type. Consult your lid diagram to confirm which relay is safe to swap!
  2. Carefully pull out the known good relay (e.g., horn relay) and the suspected fuel pump relay.
  3. Insert the known good relay into the fuel pump relay socket (position #6).
  4. Turn the ignition key to "ON." Listen for the fuel pump prime sound (2-second whir from the rear).
  5. Attempt to start the engine.
    • If the fuel pump now primes and the engine starts: The original fuel pump relay is faulty.
    • If there's still no prime sound/no start: The problem likely lies elsewhere (fuse, wiring, pump, ECU signal).
  6. Important: Remember to swap the relays back to their original positions once testing is complete.

Method 2: Physical Inspection and Bench Test (More Involved)

  1. Remove the Relay: Carefully pull the relay straight out of its socket in position #6.
  2. Visual Inspection: Examine the relay terminals and the socket terminals for any signs of corrosion, melting, burning, or damage. Clean any corrosion gently with electrical contact cleaner and a small brush if found.
  3. Shake Test: Gently shake the relay. If you hear anything rattling loose inside, the relay is likely bad.
  4. Bench Testing with Multimeter (Resistance Check - Ohms):
    • Set your multimeter to measure resistance (Ohms, Ω symbol).
    • Identify the relay terminals. Look for a diagram on the relay body or search online for a standard 4 or 5-pin automotive relay diagram. Typically:
      • Two terminals belong to the relay coil (lower resistance, usually 50-150 ohms).
      • Two terminals belong to the switched contacts (normally open, infinite resistance when coil is not powered).
    • Measure resistance across the coil terminals. You should get a reading typically between 50 and 150 ohms. A reading of "OL" (Over Limit) or infinite resistance means the coil is broken – relay is bad. A reading of 0 ohms means the coil is shorted – relay is bad.
    • Measure resistance across the switched contact terminals (usually the heavier gauge terminals). With the coil not energized, you should read "OL" or infinite resistance (open circuit). If you read low resistance, the contacts are fused or stuck closed – relay is bad.
  5. Bench Testing with Multimeter (Continuity Check - Diode Symbol/Beeper):
    • Set multimeter to continuity (usually a diode symbol or sound wave symbol). This mode beeps when there's a complete circuit (low resistance).
    • Test the coil: Place probes on the two coil terminals. You should not get continuity (no beep). (Continuity mode expects very low resistance; the coil's 50-150 ohms is usually too high to trigger continuity beep on most meters). This is normal.
    • Test the contacts: Place probes on the two main switched contact terminals. You should not get continuity (no beep) when the coil is not powered. If you get continuity (beep), the contacts are fused/stuck closed – relay is bad.
  6. Bench Testing with Jumper Wires & Power (Advanced):
    • Requires: A 12V power source (like a small battery or power supply), two jumper wires with alligator clips.
    • Identify the coil terminals (usually two smaller terminals).
    • Connect one jumper wire from the positive (+) terminal of your 12V source to one coil terminal on the relay.
    • Connect the other jumper wire from the negative (-) terminal of your 12V source to the other coil terminal on the relay. You should hear and feel a distinct "click" as the relay energizes.
    • Set your multimeter to continuity (beeper mode).
    • Place probes on the two main switched contact terminals. You should now get continuity (beep) when the coil is powered. If you don't, the contacts are not closing – relay is bad.
    • Remove power from the coil. The continuity beep should stop. If it doesn't, the contacts are stuck closed.

Replacing the 1993 Honda Accord Fuel Pump Relay

If testing confirms the relay is faulty, replacement is straightforward:

  1. Purchase a New Relay:
    • OEM Part Number: While specific numbers can vary slightly, common Honda OEM numbers for this era include 39400-SR0-003 or 39400-S04-A01. Bringing your old relay to the parts counter is the best way to match it.
    • Aftermarket: Many brands make compatible relays. Bosch 0332019150 is a very common and reliable aftermarket equivalent. Standard Motors RY291 is another. Confirm compatibility for "1993 Honda Accord Fuel Pump Relay."
  2. Remove the Old Relay: Ensure the ignition is OFF. Locate the relay in position #6 of the underhood fuse box. Grasp it firmly and pull it straight out of its socket. Avoid excessive wiggling.
  3. Install the New Relay: Orient the new relay so its terminals match the socket. Align it carefully and push it straight down into the socket until it seats fully. You should feel it click into place.
  4. Test the Repair: Turn the ignition key to "ON." You should now hear the fuel pump prime for about 2 seconds. Attempt to start the engine. It should start normally.
  5. Replace the Fuse Box Cover: Snap the cover securely back onto the fuse box.
  6. Dispose of the Old Relay: Recycle the old relay if possible.

Safety Precautions and Tips

  • Disconnect Battery (Optional but Recommended): For absolute safety, especially if probing terminals, disconnect the negative battery terminal before removing or testing relays. Reconnect it after installation.
  • Avoid Short Circuits: Be extremely careful when testing relays in the socket or using jumper wires. Accidental contact between terminals or to ground can cause sparks, blow fuses, or damage wiring.
  • Use Correct Tools: Needle-nose pliers can help remove a stubborn relay but grip the plastic body, not the terminals, to avoid bending them.
  • Check the Fuse First: Before blaming the relay, always check the fuel pump fuse. In the 1993 Accord, this is usually a 15-amp fuse located inside the car, in the dashboard fuse box on the driver's side. Consult your owner's manual or fuse box diagram. A blown fuse points to a different problem (like a short circuit), and replacing the relay won't help if the fuse is blown.
  • Listen for the Pump: The fuel pump prime sound is your best audible clue. Learn what it sounds like when your car is working properly.
  • Consider Age: Relays are electro-mechanical devices with moving parts. After 30+ years, failure is common. Replacement is inexpensive and good preventative maintenance if you experience intermittent issues.

When to Seek Professional Help

While replacing the fuel pump relay is generally simple, consider professional diagnosis if:

  • Replacing the relay doesn't solve the no-start problem.
  • You are uncomfortable working with electrical components or testing procedures.
  • You suspect deeper electrical issues (damaged wiring, faulty ECU).
  • You've confirmed the relay and fuse are good, but the fuel pump still doesn't run (requires more advanced testing of power, ground, and pump itself).

Conclusion

Locating the fuel pump relay in your 1993 Honda Accord is the first critical step in diagnosing a no-start condition related to fuel delivery. Remember, it's found in position #6 within the underhood fuse and relay box near the driver's side strut tower. Always confirm its identity using the diagram on the fuse box cover. Testing the relay is relatively simple, either by swapping it with a known good identical relay or using a multimeter. Replacement is quick and affordable. By understanding the location, function, and testing procedures for this vital component, you can effectively troubleshoot and resolve fuel pump power issues, getting your reliable Accord back on the road. If problems persist after relay replacement, further investigation into fuses, wiring, the fuel pump itself, or the ECU signal will be necessary.

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