02 Honda Accord Fuel Pump Relay: Symptoms, Location, Testing, & Replacement Guide

Your 2002 Honda Accord won't start or randomly stalls? The fuel pump relay is a prime suspect. This small, critical electrical component acts as a switch, delivering the high current needed by the fuel pump when you turn the key. When it fails, your Accord loses fuel pressure and won't run. Understanding its function, recognizing failure signs, knowing where it's located, and learning how to test or replace it are essential skills for any 2002 Accord owner facing starting or stalling issues. This comprehensive guide covers everything you need to know about the 02 Honda Accord fuel pump relay.

The Vital Role of the Fuel Pump Relay in Your 02 Accord

The fuel pump in your 2002 Honda Accord requires significant electrical current to operate. Routing this high current directly through the ignition switch and engine control circuits is impractical and risky. The ignition switch isn't designed to handle that load repeatedly, and sensitive engine control modules could be damaged. This is where the relay comes in.

Think of the fuel pump relay as a heavy-duty remote-controlled switch. It uses a small, low-current signal from the Powertrain Control Module (PCM) – triggered when you turn the key to the "ON" or "START" position – to activate an internal electromagnet. This magnet closes much larger, heavy-duty internal contacts within the relay. These closed contacts then complete the high-current circuit directly from the battery fuse to the fuel pump itself. Essentially, the relay allows the car's computer to safely control the much larger electrical load required by the pump. When the relay malfunctions, it fails to complete this critical circuit, starving the engine of fuel.

Common Symptoms of a Failing 2002 Honda Accord Fuel Pump Relay

A bad fuel pump relay in your sixth-generation Accord (specifically the 1998-2002 model years) typically manifests in one or more of these ways:

1. No Start Condition (Most Common): This is the classic symptom. You turn the key, the starter cranks the engine strongly, but the engine never fires up and runs. It cranks but won't start. You don't hear the brief humming sound from the rear seat area (where the fuel pump is located) for 1-2 seconds when you first turn the key to the "ON" position (before cranking).
2. Engine Stalling While Driving: An intermittent relay can cause the engine to suddenly die while driving, as if the fuel was instantly cut off. The car might restart after cooling down for a few minutes, or it might refuse to restart immediately.
3. Intermittent Starting Problems: The car starts fine sometimes and won't start other times, often without any apparent pattern or logic. This inconsistency is a hallmark of a relay whose internal contacts are worn or becoming corroded.
4. Clicking Sound from Relay: You might hear a rapid, repeated clicking sound coming from the under-hood fuse/relay box when you turn the key. This can indicate a relay struggling to stay engaged or cycling rapidly due to internal failure.
5. Check Engine Light (Sometimes): While not always present, a failing relay can sometimes trigger Diagnostic Trouble Codes (DTCs) like P0230 (Fuel Pump Primary Circuit Malfunction) or P0627 (Fuel Pump Control Circuit Open). However, the absence of a check engine light does not rule out the relay as the cause.
6. No Fuel Pressure: This is a direct consequence but requires testing. Using a fuel pressure gauge on the fuel rail will typically show zero or extremely low pressure.

Locating the Fuel Pump Relay in Your 2002 Honda Accord

Finding the suspect relay is the first practical step. In the 2002 Accord, the main fuse and relay box is located in the engine compartment, typically on the driver's side (left side) near the firewall and strut tower. It's a black rectangular box.

1. Open the Hood: Safely secure the hood.
2. Locate the Under-Hood Fuse/Relay Box: Identify the primary black plastic box on the driver's side. It will have a lid.
3. Remove the Fuse Box Cover: The cover is usually secured with plastic clips. Squeeze or press these clips gently and lift the cover off. Place it aside safely.
4. Identify the Fuel Pump Relay: Look at the diagram printed on the underside of the fuse box lid. This diagram is your map. It clearly labels each fuse and relay position. The specific position might vary slightly between the 4-cylinder and V6 models, but it's commonly in one of the corners.
   • Common locations include Position #9, #14, #19, or #21. DO NOT GUESS. ALWAYS use the diagram on the underside of your specific lid to identify the correct slot labeled FUEL PUMP or PGM-FI MAIN (sometimes the fuel pump relay is also designated as the main relay for the fuel injection system in Hondas of this era). The relay itself might even have its position number printed on the plastic base.
   • The relay will be a small, typically square or rectangular, black plastic cube (about 1 inch x 1 inch or slightly larger) with 4 or 5 electrical pins protruding from the bottom. Compare it to the picture in the diagram.

How to Test the 02 Honda Accord Fuel Pump Relay

Testing is crucial before spending money on a replacement. You need a basic digital multimeter. You can perform two main tests:

Test 1: Listening/Touch Test (Preliminary Check)

1. Find the relay location using the lid diagram.
2. With the key OFF, carefully pull the relay straight up out of its socket. Note its orientation.
3. Turn the ignition key to the "ON" position (do not crank). You should hear the fuel pump motor hum for about 2 seconds near the rear seat.
4. Reinstall the relay firmly into its socket.
5. Turn the ignition key to "ON" again.
6. Listen: Place your ear near the relay. Do you hear/feel a distinct audible "click" inside the relay within 1-2 seconds of turning the key to ON?
7. Feel: Lightly touch the top of the relay. You should feel a faint "click" vibration as it energizes when the key is turned on.
8. Result: No audible or tactile click? This strongly indicates the relay isn't activating. Note: This doesn't guarantee the contacts are good internally, only that the coil isn't energizing or engaging the switch mechanism.

Test 2: Multimeter Resistance Test (Pin Check)
This tests the integrity of the internal switching contacts.

1. Remove the relay from its socket.
2. Identify the pins. Look at the bottom. You'll see 4 or 5 pins. Turn the relay so the pins face you. Looking at the standard markings:
   • Pins 1 & 2: These are typically the control coil pins (activates the relay). We don't test these directly in this resistance test.
   • Pin 3: Common terminal (connects to power source input).
   • Pin 4: Normally Open (NO) terminal (connects to Pin 3 only when the relay is activated). This is the pin that connects to the output going to the fuel pump.
   • (A 5-pin relay might have an additional Normally Closed terminal, usually not used in this fuel pump application)
   • Key: Consult a relay diagram specific to the part number or use the socket layout. The pin numbers are often molded into the plastic base near the pins.
3. Set your digital multimeter to measure Resistance (Ohms, Ω).
4. Touch the meter probes to Pin 3 (Common) and Pin 4 (Normally Open).
5. Reading: With the relay de-energized (just sitting on the bench), you should measure Infinite Resistance (OL or overload). This indicates the switch contacts inside are open.
6. Apply Power to the Coil: Now, apply a small voltage (9V or 12V DC is fine - a 9V battery works well) across Pin 1 and Pin 2. Observe polarity if you know it, or try both ways if not; it usually won't harm the coil.
   • You should hear/feel a distinct click as the relay energizes.
7. Retest Resistance: While keeping power applied to Pin 1 and 2 (the coil energized), retouch the meter probes to Pin 3 (Common) and Pin 4 (Normally Open).
8. Reading: You should now measure VERY LOW Resistance (close to 0 Ohms, maybe 0.1 - 0.5 Ohms). This indicates the internal switch contacts are now closed and conducting properly.
9. Result:
   • Failed Test 1 (No Click): Relay doesn't activate. Likely faulty coil or mechanism.
   • Failed Test 2 Step 5: Resistance is low (not OL) when the relay should be OFF: The contacts are stuck or welded shut. Faulty.
   • Failed Test 2 Step 8: Resistance is high/infinite when the relay should be activated and contacts closed: The contacts are burned out, corroded, or not making connection. Faulty.
   • If it passes both tests electrically, the problem might lie elsewhere.

The Swap Test (Functional Check Using a Known Good Relay)

One of the most reliable diagnostic methods is swapping the suspected fuel pump relay with a known good, identical relay from another, non-critical circuit in the same fuse box. This leverages Honda's common relay design.

1. Identify the fuel pump relay position (e.g., #14). Identify a relay with the exact same part number in another slot. Common choices include the radiator fan relay, A/C compressor clutch relay, or fog light relay. CRITICAL: Verify the replacement relay has identical pin layout and numbers and matches the part number stamped on the suspect relay.
2. Carefully remove the suspect fuel pump relay.
3. Carefully remove the known good relay from its non-critical socket.
4. Install the known good relay into the fuel pump relay socket. Ensure it's seated firmly and completely.
5. Attempt to start the car. Does the engine start? Do you hear the fuel pump prime?
6. Result:
   • Engine Starts: The original fuel pump relay is faulty. Replace it.
   • Engine Still Does Not Start: The original relay might be okay, OR the replacement relay is also faulty (less likely), OR the problem lies elsewhere (fuel pump itself, main fuse, wiring, PCM). Further diagnosis needed.

Replacing the Fuel Pump Relay in Your 2002 Honda Accord

Once testing confirms a faulty relay, replacement is straightforward:

1. Purchase the Correct Replacement:
   • OEM: Best option. Honda Part Number: 39400-S84-A01 (This supercedes older numbers). Denso is the primary OEM supplier. Use this number at the Honda dealer parts counter.
   • High-Quality Aftermarket: Brands like Bosch, Denso (sold aftermarket), Standard Motor Products (SMP), or Blue Streak are reliable choices. Ensure it matches the OEM specifications and pin layout. Avoid the cheapest no-name relays.
2. Locate the Relay: Using the lid diagram, locate the fuel pump relay socket under the hood. Verify it's the correct one.
3. Remove the Old Relay: With the ignition OFF, grasp the relay firmly and pull it straight up out of its socket. It should come out with moderate effort. Avoid excessive wiggling.
4. Inspect the Socket: Briefly check the socket for any obvious corrosion, bent pins, or debris. Blow it out gently with compressed air if necessary.
5. Install the New Relay: Align the new relay's pins perfectly with the holes in the socket. Push it firmly and squarely straight down until it is fully seated. You should feel it click or lock into place. Ensure it's seated to the same depth as the surrounding relays.
6. Test Operation: Turn the ignition key to the "ON" position. You should hear the new relay click within 1-2 seconds and hear the fuel pump prime for 2 seconds near the rear seat. Attempt to start the engine.

Crucial Notes on PGM-FI Main Relay vs. Fuel Pump Relay (2002 Accord)

Honda terminology on relay boxes can sometimes be confusing. In the sixth-generation Accord:

• Fuel Pump Relay: As discussed, this relay directly controls power to the fuel pump motor itself. This is the relay our guide focuses on testing and replacing.
• PGM-FI Main Relay (Sometimes Listed as MAIN or INJ Relay): This is a different, very important relay. It powers the entire Engine Control Module (ECM/PCM) and the fuel injectors. When this fails, you get a "silent death" – no fuel pump prime and the engine won't crank or may crank but act completely dead electronically (no injector pulse, no spark). Symptoms are similar but broader than just no fuel pump operation. Diagnosing and replacing the PGM-FI Main relay involves a similar process, but the location and symptoms differ.

*Always, always refer to the diagram on your specific under-hood fuse box lid to identify which relay slot controls the FUEL PUMP.* Do not confuse it with the MAIN relay slot.

Why Honda Fuel Pump Relays Fail in 2002 Accords

Fuel pump relays are electro-mechanical devices with moving parts and electrical contacts. Common failure modes include:

• Worn/Burned Contacts: Repeated cycling over decades causes the internal metal contacts to pit, corrode, or weld together. This leads to open circuits (no connection) or stuck contacts (always on or fused).
• Coil Failure: The small electromagnetic coil inside can fail open (broken wire) or short internally, preventing the relay from activating.
• Internal Solder Joint Failure: Vibration and thermal cycling can cause solder joints on the relay's internal circuit board to crack.
• Contamination/Moisture: While sealed, ingress of moisture or corrosive elements over very long periods can lead to internal corrosion.
• Heat: The relay heats up during operation. Continuous exposure to high under-hood temperatures accelerates component aging. Poor connections in the socket generating heat can exacerbate this.

OEM Denso or quality replacements generally last many years. Cheap, low-quality relays fail much sooner.

Fuel Pump Relay Cost and Availability

• OEM Honda (Denso): $25-$50 USD.
• Quality Aftermarket (Bosch, Denso, SMP): $15-$30 USD.
• Budget Aftermarket: $5-$15 USD (Use with caution; reliability varies greatly).

Parts are readily available from Honda dealers, major auto parts stores (AutoZone, Advance Auto Parts, O'Reilly Auto Parts, NAPA), and online retailers (RockAuto, Amazon).

When It's NOT the Fuel Pump Relay: Other Possible Causes

If replacing the relay doesn't fix the no-start or stalling issue, investigate these systems:

1. The Fuel Pump Itself: The pump motor can burn out. Test for power and ground at the pump connector (located under the rear seat access panel) to confirm the relay command is getting there. Listen for pump noise. Confirm fuel pressure at the rail. Replacing a failed pump requires dropping the fuel tank.
2. Fuel Pump Fuse: Check the main fuse powering the fuel pump circuit. It's usually a large fuse (15A, 20A, or 30A) in the same under-hood fuse box. Look for one labeled "FUEL PUMP" or "PCM". Inspect it visually and test it with a multimeter for continuity.
3. Ignition Switch: A faulty ignition switch may not send the "ON" signal to the PCM to activate the fuel pump relay. Symptoms often include loss of dash lights or multiple electrical failures at once.
4. PCM/Fuel Pump Control Module Issues: Rare, but failure of the PCM itself or its output driver controlling the relay coil could prevent activation. Requires specialized diagnostics.
5. Wiring Harness Damage: Corrosion, breaks, or shorts in the wiring between the fuse box and the relay, the relay and the pump, or within the ground circuits can cause identical symptoms. Check for chafed wires, especially near connectors or moving parts. Wiggle tests of the harness while trying to start can sometimes reveal an intermittent fault.
6. Security System (Immobilizer) Fault: If equipped, a problem with the immobilizer system preventing recognition of your key can disable the fuel pump. Often accompanied by a flashing security light on the dash. Requires dealer-level diagnostics or reprogramming.
7. Main Battery Cables & Grounds: Severe corrosion or looseness at major battery cables or engine/body grounds can prevent sufficient current flow for any component, including the fuel pump circuit.

Conclusion: The Critical Link for Your 2002 Accord's Fuel System

The humble fuel pump relay is a simple yet vital component in your 2002 Honda Accord's fuel delivery system. Its failure leads directly to frustrating no-start conditions or dangerous stalling while driving. By understanding its function, learning to recognize the symptoms, knowing precisely where it's located under the hood (using the lid diagram!), mastering basic testing techniques, and performing a straightforward replacement, you can quickly resolve one of the most common causes of fuel-related problems in your Accord. Keep a reliable spare relay in your glove compartment – it's inexpensive insurance against getting stranded. Always prioritize correct identification and safety, and if testing points elsewhere, be prepared to investigate the fuel pump, fuses, and related wiring to get your trusty Honda back on the road reliably.