2008 Honda Fit Fuel Pump Relay Location: A Practical Owner’s Guide

The bottom line up front: If you own a 2008 Honda Fit and need to find the fuel pump relay, stop searching under the hood. On this model, the fuel pump relay—officially called the PGM-FI main relay 2—is located inside the passenger compartment, mounted on the under-dash fuse/relay box on the driver’s side . It is a blue, cube-shaped relay that sits in a small relay holder attached to the fuse box, and you must remove the driver’s side under-cover to reach it . This guide walks you through exactly where it is, how to confirm it’s the culprit, and how to replace it without guesswork.

Where Exactly Is the Fuel Pump Relay on a 2008 Honda Fit?

The 2008 Honda Fit belongs to the second generation (GE/GP/GG chassis, 2007–2015), and its fuse and relay layout differs significantly from the first-generation model . For the 2008 model year specifically, the fuel pump relay is not in the engine bay—it lives inside the cabin.

Here is the precise step-by-step to get to it:

1. Turn the ignition switch OFF and disconnect the negative battery terminal (safety first, especially if you’ll be probing wires).

2. Remove the driver’s side under-cover. This is the plastic panel beneath the dashboard, above the driver’s footwell. It is typically held by a few clips or screws .

3. Locate the under-dash fuse/relay box. It is mounted on the driver’s side, behind the under-cover, near the steering column area . On left-hand-drive models, it sits directly under the steering column trim .

4. Slide the relay holder out of the fuse box. The PGM-FI main relay 2 (the fuel pump relay) is housed in a separate relay holder that clips onto the fuse box. Gently slide or unclip the holder to access the relay .

5. Identify the blue relay. The fuel pump relay is the blue relay in the holder . In some service documents, it is also referred to simply as the “main relay 2” (blue) . The brown relay next to it is the PGM-FI main relay 1, which powers the ECU and injectors—do not mix them up .

6. Remove the relay and inspect it. Use relay pliers if space is tight. Check both the relay pins and the socket for signs of melting, corrosion, or burning .

Note for 2008 vs. other years: The second-generation Fit (2007–2015) uses the same general layout, but some years or trim levels may have slightly different relay holder configurations . If your car has an anti-theft system, additional relays may be present nearby .

What Does the Fuel Pump Relay Do?

The fuel pump relay is the electrical switch that delivers power from the battery to the fuel pump. When you turn the ignition to the ON position, the engine control module (ECM/PCM) sends a small signal to the relay’s coil. This closes the internal contacts, allowing high current to flow to the fuel pump for about 2 seconds to build pressure in the fuel lines . Once the engine starts, the relay stays closed, keeping fuel flowing continuously.

If the relay fails, the fuel pump never gets power—your engine will crank but won’t start. No fuel pressure, no combustion.

How to Confirm the Relay Is Bad (Before You Buy a New One)

A dead fuel pump relay produces symptoms that are easy to confuse with a failing fuel pump . Here is a quick diagnostic sequence:

1. Listen for the prime. Turn the ignition key to ON (do not crank). Put your ear near the fuel fill port (cap removed) or the rear of the car. You should hear a brief hum from the fuel pump for 2 seconds . No sound = no power to the pump.

2. Feel the relay. With the ignition OFF, place a finger on the blue relay and have someone turn the key to ON. You should feel and hear a distinct click as the relay energizes . No click = the relay coil is not being triggered, or the relay is dead .

3. Swap the relay. If you have a known-good relay of the same type (e.g., from another circuit like the horn or main relay), swap it in temporarily and try again . If the car starts, your relay was faulty. Make sure the replacement has the same part number or equivalent rating.

4. Check the fuse first. Before condemning the relay, check the fuel pump fuse in the under-dash fuse box. On the 2008 Fit, the fuel pump fuse is rated 15 A . A blown fuse will produce the exact same “no prime, no start” symptom.

5. Use a jumper wire (advanced). As a last resort, you can jumper the relay socket’s wide terminals to supply power directly to the pump (use a fused jumper wire rated 15 A). If the pump runs, the problem is in the relay control circuit, not the pump .

Common Symptoms of a Failing Fuel Pump Relay on a 2008 Fit

Here is what you will typically notice when the relay starts to fail:

  • Engine cranks but will not start (the most common symptom)
  • No fuel pump prime (no humming sound when the key is turned ON)
  • Intermittent stalling while driving, then the engine restarts after cooling down
  • Loss of power under load if the relay contacts are arcing
  • Green key indicator flashing on the dash (in some cases, this indicates the immobilizer has lost communication due to a relay/ECU power issue)

If you experience these symptoms, do not assume the fuel pump itself is dead. Many owners replace the entire pump assembly, only to find the relay was the real issue .

Replacement Cost and Part Information

The good news: a fuel pump relay is inexpensive.

  • OEM part number: For the 2008 Honda Fit, the genuine fuel pump relay is part number 39794-SDA-004 (Denso), which replaces 39794-SDA-305 and 39794-SDA-003 . It fits 2007–2013 Honda Fit models .
  • Average cost of the part: Between $20 and $50 for the relay itself .
  • Labor cost: If you pay a mechanic, expect $30 to $150 depending on accessibility and shop rates .
  • DIY cost: $0 (your own labor) plus the part. The job takes about 15 minutes once you have the under-cover off.

If you choose to test the relay with a multimeter before buying:

  • Find the two thin control-circuit terminals and the two thick power-circuit terminals (refer to the diagram on the relay housing) .
  • Use an ohmmeter to measure continuity across the power terminals—it should read open (no continuity) when the relay is de-energized .
  • Apply 12V across the control terminals; you should hear a click and see continuity across the power terminals .

A Few Important Safety Tips

  • Always disconnect the battery negative terminal before working near the fuse box or fuel system .
  • Relieve fuel pressure if you plan to disconnect any fuel lines. To do this, remove the main relay 2, start the engine, and let it idle until it stops, then turn the ignition OFF .
  • Do not use an unfused jumper wire to bypass the relay—use a fused jumper rated at 15 A or less to protect the circuit .

Why Choose a KEMSO Fuel Pump for Your Honda Fit?

If your diagnosis points to the fuel pump itself—not just the relay—it pays to choose a reliable replacement. KEMSO is a trusted brand that specializes in high-performance fuel pumps designed to meet or exceed OEM specifications. Every KEMSO fuel pump is built as a direct OEM replacement, meaning it bolts in and plugs in just like the factory unit, with no modifications required.

Here is what sets KEMSO apart:

1. High-Performance Build: KEMSO pumps are engineered for consistent fuel delivery under demanding conditions, whether you drive a stock daily commuter or a modified performance build.

2. True OEM Replacement Fitment: Every KEMSO fuel pump is manufactured to match the exact dimensions, connectors, and flow characteristics of the original part. You get a hassle-free install every time.

3. Lifetime Warranty: KEMSO stands behind its products with a lifetime warranty, giving you peace of mind that your fuel system investment is protected for as long as you own the vehicle.

If you need a replacement fuel pump for your 2008 Honda Fit or any other vehicle, visit KEMSO’s official store to browse their full lineup:

👉 https://www.kemsoracing.com/

Their catalog covers everything from Honda and Subaru to BMW, Ducati, and Kawasaki—all backed by their performance-focused, warranty-protected reputation.

Final Recap

To sum it up simply:

  1. The 2008 Honda Fit fuel pump relay is under the dash, not under the hood. It is the blue relay in the PGM-FI relay holder on the driver’s side fuse box .
  2. Before replacing the pump, check the relay and the 15 A fuel pump fuse .
  3. Listen for the 2-second prime when turning the key ON—if you hear nothing, suspect the relay .
  4. Replacing the relay is a 15-minute DIY job that costs only $20–$50 in parts .

If you confirm the fuel pump itself is dead, choose a dependable replacement like a KEMSO fuel pump from https://www.kemsoracing.com/—high-performance, OEM-replacement fitment, and backed by a lifetime warranty.


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