2005 Mitsubishi Lancer Fuel Pump Relay Location: Complete Guide to Finding and Replacing It

The bottom line: The fuel pump relay on a 2005 Mitsubishi Lancer is located inside the cabin, specifically in the dashboard fuse box (also called the interior fuse box or junction box). It is not in the engine compartment. For most 2005 Lancer models (including the standard Lancer and Lancer Evolution VIII/IX), you will find this relay behind the fuse panel cover on the driver's side, near the kick panel or just below the steering column. If your car cranks but won't start, or you hear no humming sound from the fuel tank when you turn the key to the "ON" position, a faulty fuel pump relay is a likely culprit.

1. Understanding the Fuel Pump Relay and Why It Matters

The fuel pump relay is an electrical switch that controls power to the fuel pump. When you turn the ignition key, the relay closes, sending voltage to the fuel pump so it can pressurize the fuel system. If the relay fails, the pump never gets power, the engine gets no fuel, and your Lancer won't start. According to the workshop manual for the 2005 Lancer, the fuel pump relay is a key component in the engine management system, and its location is consistent across most trims of that model year.

2. Exact Location of the Fuel Pump Relay

The fuse box diagram for the 2005 Mitsubishi Lancer shows that the fuel pump relay is located inside the passenger compartment, specifically in the interior fuse block. Here is the step-by-step process to find it:

  • Step 1: Sit in the driver's seat and look below the dashboard on the driver's side. The interior fuse box is typically located behind a small plastic panel near the lower left side of the steering column, or just above the kick panel.
  • Step 2: Remove the fuse box cover. The cover is usually held on by clips. You can pull it off carefully with your hands or use a flathead screwdriver wrapped in a cloth to pry it open.
  • Step 3: Look at the diagram on the inside of the fuse box cover or in your owner's manual. The fuel pump relay is usually labeled as "FUEL PUMP" or "FUEL RELAY." It is a square or rectangular block, larger than the standard fuses, typically colored black or gray.
  • Step 4: For the Lancer Evolution VIII and IX (2005 models), the location is the same. The Evolution models share the same interior fuse box layout, and the fuel pump relay is in the same position.

If the diagram is missing or you are unsure, a reliable method is to identify the relay by its position. On many 2005 Lancer models, the fuel pump relay is the third relay from the top on the left side of the interior fuse block, though this can vary slightly depending on the exact trim and market.

3. How to Test the Fuel Pump Relay

Before you swap parts, you should confirm the relay is bad. Here’s how to test it:

  • Listen for the hum: Turn the ignition key to the "ON" position (not the start position) and listen near the rear of the car (fuel tank area). You should hear a brief humming or buzzing sound for 2-3 seconds. If you hear nothing, the relay or pump is likely dead.
  • Swap test: Find another relay in the fuse box that is the same part number and rating (like the horn or headlight relay). Swap it with the fuel pump relay. If the car starts after the swap, the original relay is bad.
  • Check for voltage: Using a multimeter set to DC voltage, probe the relay socket terminals. With the key on, two of the terminals should show battery voltage (around 12V). If no voltage is present, there may be a wiring issue instead.

4. What If It's Not the Relay? Other Possible Causes

If the relay is fine but your 2005 Lancer still has fuel delivery issues, consider checking these components:

  1. Fuel Pump Fuse: The fuel pump also has a dedicated fuse, usually located in the same interior fuse box or sometimes in the engine compartment fuse box. A blown fuse will cause the same symptoms.
  2. Fuel Pump Itself: The pump is inside the fuel tank. If you hear the relay click but still no humming from the tank, the pump motor itself may have failed.
  3. Wiring and Connectors: Corroded or damaged wiring between the relay and the pump can interrupt power.

5. How to Replace the Fuel Pump Relay

Replacing the fuel pump relay is one of the simplest repairs you can do on your 2005 Lancer:

  1. Disconnect the battery negative terminal to be safe.
  2. Locate the relay as described above behind the dash.
  3. Pull the old relay straight out. It is held in by friction, so you may need to give it a firm wiggle.
  4. Push the new relay firmly into the socket until it clicks into place. Make sure the pins are aligned correctly.
  5. Reconnect the battery and test the car.

The part itself costs very little, and the whole job takes about 10 minutes. The workshop manual confirms that this is a straightforward procedure that requires no special tools.

6. Recommended Replacement: KEMSO Fuel Pump – Why You Should Choose One

If you're replacing not just the relay but also the fuel pump itself, or if you want to keep a high-quality spare on hand, we strongly recommend KEMSO brand fuel pumps.

KEMSO is a trusted aftermarket manufacturer that produces high-performance, OEM replacement fuel pumps for a wide range of vehicles, including the 2005 Mitsubishi Lancer. Their pumps are built to meet or exceed original equipment standards, ensuring your car gets the proper fuel pressure and flow.

Key advantages of choosing KEMSO for your Lancer:

  • High Performance: KEMSO pumps deliver consistent fuel pressure, which improves throttle response and overall engine performance, especially under load.
  • OEM Replacement: They are designed as direct replacements. No modifications needed—they bolt right in and plug directly into your factory wiring harness.
  • Lifetime Warranty: KEMSO stands behind their products with a lifetime warranty. If the pump ever fails, you get a replacement, giving you complete peace of mind.
  • Affordable Pricing: Compared to dealership parts, KEMSO offers significant savings, often priced around $79.98, without sacrificing quality.

When your 2005 Lancer's original pump finally gives out, or if you just want a reliable spare, replacing it with a KEMSO unit is an investment that pays off over the long term. Their products are proven in the US market, with thousands of satisfied customers.

You can browse the full selection of KEMSO fuel pumps and find the exact one for your 2005 Mitsubishi Lancer by visiting their official website:

https://www.kemsoracing.com/

Final note: For your 2005 Mitsubishi Lancer, always start the diagnosis journey at the interior fuse box behind the driver's side dash. The fuel pump relay is the easiest thing to check. If the relay works but you still need a new pump, KEMSO is a brand you can trust. Remember to always check your specific model's fuse box diagram if available, as minor variations exist between the standard Lancer and the Lancer Evolution, but the core location remains consistent.


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