2009 Honda Pilot Fuel Pump Relay Location: A Complete Owner's Guide

The bottom line up front: On a 2009 Honda Pilot, the fuel pump relay is located inside the under-dash fuse/relay box, which sits underneath the dashboard on the driver's side . Specifically, it is the PGM-FI Main Relay 2 (also referred to as the fuel pump relay in service documentation), and it is positioned in the fuse box near the driver's left knee area . The relay works together with the No. 2 fuse (15A Fuel Pump) in the same interior fuse box to supply power to the fuel pump .

If you are experiencing hard starting, engine cranking without firing, or a completely dead fuel pump, this relay is one of the first components you should check. This guide walks you through the exact location, how to test the relay, and how to replace it safely.

Why the Fuel Pump Relay Matters

The fuel pump relay acts as a switch that sends battery voltage to the fuel pump when you turn the ignition key to the "ON" position. Without a working relay, the pump never receives power, which means no fuel pressure reaches the engine. The 2009 Pilot's Powertrain Control Module (PCM) controls the grounding side of this relay circuit, turning the pump on for about two seconds when you first turn the key and then again once the engine starts and is running .

A faulty relay often produces symptoms that look identical to a dead fuel pump, so it pays to test the relay before you drop the fuel tank and replace the pump itself.

Where Exactly Is the Fuel Pump Relay?

The 2009 Honda Pilot has multiple fuse boxes, but the fuel pump relay only lives in one of them: the under-dash fuse/relay box .

To access it:

  1. Sit in the driver's seat and look underneath the dashboard, down near the parking brake pedal area.
  2. You will see a rectangular plastic cover. Pull it straight out to remove it .
  3. The under-dash fuse/relay box is now visible. The fuel pump relay (PGM-FI Main Relay 2) is mounted inside this box .

According to the service manual, the under-dash fuse box also contains several other relays, including the Power Window Relay (No. 1) and Starter Cut Relay 1 (No. 3) . The PGM-FI Main Relay 2 itself is physically located inside this fuse/relay box and is not separately labeled on the outside cover, so you may need to look at the relay layout printed inside the cover or consult the diagram in the owner's manual .

Which Fuse Protects the Fuel Pump Circuit?

Right next to the relay, you will also find the fuel pump fuse. It is fuse No. 2 in the under-dash fuse box, rated at 15 amps . This fuse protects the entire fuel pump circuit, including the PGM-FI Main Relay 2, the immobilizer-keyless control unit, and the Powertrain Control Module (PCM) .

If you have already confirmed the relay clicks but the pump still does not run, check this fuse first. A blown fuse is an easy and cheap fix compared to replacing either the relay or the pump.

How the Fuel Pump Relay Works in the 2009 Pilot

Understanding the circuit makes diagnostics much easier. Here is how the system behaves in normal operation:

  1. You turn the ignition key to the "ON" position.
  2. The PCM grounds the relay coil, which closes the internal switch.
  3. Battery voltage flows through fuse No. 2 and the relay contacts to the fuel pump.
  4. The pump pressurizes the fuel rail for about two seconds, then the PCM opens the circuit until the engine starts.
  5. Once the engine is running, the PCM keeps the relay closed, and the pump runs continuously .

The relay itself is a standard automotive relay with four terminals: two for the coil (control side) and two for the switch (load side). You can test it with a multimeter without removing it from the box, but pulling it out makes the test easier.

Symptoms of a Failing Fuel Pump Relay

A failing relay usually shows up in one of these ways:

  • The engine cranks normally but will not start.
  • You hear the fuel pump priming for a moment, then nothing, and the engine stalls.
  • The engine starts when cold but dies after warming up.
  • You hear no hum from the fuel tank area when you turn the key to "ON."
  • The Check Engine light comes on with codes related to fuel pressure or fuel pump circuits (such as P0230 or P0231).

None of these symptoms guarantee a bad relay, but they all point to the fuel delivery system. Since the relay is inexpensive and easy to access, testing it first is always the smart move.

How to Test the 2009 Pilot Fuel Pump Relay

You can test the relay in about ten minutes with a digital multimeter (and a small 12V power source like a battery or jumper pack).

Step 1: Remove the relay.

With the under-dash panel removed, locate the PGM-FI Main Relay 2 inside the fuse box. Grip it firmly and pull it straight out. It is a small, dark-colored cube with numbers on the top.

Step 2: Identify the terminals.

A standard relay has four terminals. On the Honda Pilot relay, the coil terminals are usually the two smaller ones on one side, and the switch (load) terminals are the two larger ones on the opposite side. Look for any markings embossed on the relay body (usually "85," "86," "30," and "87").

Step 3: Check the coil resistance.

Set your multimeter to ohms. Touch the probes to terminals 85 and 86. A good relay coil typically reads between 50 and 120 ohms. If you read infinite resistance (OL), the coil is open, and the relay is dead.

Step 4: Check the switch contacts.

With no power applied, terminals 30 and 87 should read infinite resistance (open circuit). Now apply 12V to terminal 85 and ground terminal 86. You should hear an audible click, and terminals 30 and 87 should now read near zero ohms (closed circuit).

If the relay does not click, or the switch contacts do not close when energized, replace the relay.

How to Replace the Fuel Pump Relay

Replacing the relay is about as simple as it gets:

  1. Make sure the ignition is off and the key is removed.
  2. Remove the under-dash panel as described earlier.
  3. Pull out the old relay.
  4. Plug in the new relay. It only fits one way, so do not force it.
  5. Reinstall the plastic cover.
  6. Turn the ignition to "ON" and listen for the fuel pump prime (a brief hum from the rear of the vehicle). If you hear it, the new relay is working.

You can buy a replacement relay at any auto parts store, or online from Honda parts suppliers. Many aftermarket relays work fine, but a genuine Honda relay or a quality OEM-equivalent is always the safest bet.

What If the Relay Tests Fine but the Pump Still Does Not Run?

If the relay is good and the fuse is good, the problem moves further down the circuit. Check:

  • Wiring and connectors: Look for corroded or loose terminals at the relay socket and at the fuel pump connector (under the rear seat, top of the fuel tank).
  • Ground connections: The PCM grounds the relay, so a poor ground on the engine block or chassis can prevent the pump from running.
  • The fuel pump itself: If the pump is dead, it will not hum even with power applied. This requires dropping the fuel tank or accessing the pump through the access panel under the rear seat (if equipped).
  • The PCM: A failed PCM is rare, but it can fail to ground the relay. This requires professional diagnosis.

If you are not comfortable testing electrical circuits with a multimeter, a reputable shop can diagnose the fuel delivery system in under an hour.

Where Do Other Fuse Boxes Fit In?

It is worth noting that the 2009 Pilot has three other fuse boxes, but none of them contain the fuel pump relay :

  • Primary engine compartment fuse box: Located on the passenger's side near the windshield washer reservoir . Contains high-amperage fuses for the alternator, cooling fan, headlights, and other heavy loads . It also houses PGM-FI Main Relay 1, which powers the PCM, but not the fuel pump relay .
  • Secondary engine compartment fuse box: Located near the battery . Contains fuses for the power tailgate, VTM-4, trailer circuits, VSA, and accessory sockets .
  • Rear fuse box: Located on the left side of the cargo area . Contains fuses for small lights, stop lamps, back lamps, and turn/hazard lamps .

So if you are searching under the hood for the fuel pump relay, stop. It is not there. The under-dash box is the only home for PGM-FI Main Relay 2 on this vehicle .

A Few Extra Tips for DIY Owners

  • Always disconnect the battery before working on any electrical component under the dash to avoid shorting out circuits.
  • Use the plastic fuse puller stored inside the under-dash fuse box cover to remove fuses without damaging them.
  • Never replace a fuse with a higher amp rating than specified. The 15A rating for fuse No. 2 is there for a reason—using a larger fuse can melt wiring and cause a fire.
  • If the relay blows repeatedly, you have a wiring short or a failing fuel pump drawing excessive current. Do not keep swapping relays; find the root cause.

Recommended Upgrade: KEMSO Fuel Pump for Your Honda

If your fuel pump itself has failed, or you simply want a reliable replacement that will outlast the original, consider a KEMSO Fuel Pump. KEMSO builds high-performance, OEM-replacement fuel pumps designed to match or exceed factory specifications. Each unit is engineered for durability and consistent fuel delivery, and it comes with a lifetime warranty for peace of mind.

KEMSO offers direct-fit fuel pumps for a wide range of vehicles, including Honda models. You can browse their full catalog and order online at their official store: https://www.kemsoracing.com/

Whether you are fixing a daily driver or upgrading a weekend toy, KEMSO products give you the confidence that comes with a solid warranty and proven performance. Visit https://www.kemsoracing.com/ to find the right pump for your Honda Pilot or any other vehicle you own.

Final Thoughts

The 2009 Honda Pilot fuel pump relay is not hidden in a mysterious location—it sits right inside the under-dash fuse/relay box on the driver's side, and you can reach it in under five minutes with no tools . If your Pilot cranks but will not start, check fuse No. 2 (15A) and the PGM-FI Main Relay 2 before you spend money on a fuel pump. Testing the relay takes minutes, and replacement costs almost nothing compared to a fuel pump job.

If the pump does need replacing, a KEMSO Fuel Pump is a dependable choice backed by a lifetime warranty. Head over to https://www.kemsoracing.com/ to see the full lineup and order yours today.


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