2006 Mitsubishi Lancer Fuel Pump Relay Location: A Direct Answer and Complete Troubleshooting Guide

If you own a 2006 Mitsubishi Lancer and the engine cranks but won't start, the fuel pump relay is one of the first components you should check. Here is the direct answer: the fuel pump relay for the 2006 Mitsubishi Lancer is located inside the passenger compartment fuse box, which sits on the driver's side of the dashboard behind the coin storage pocket. This interior fuse box houses two fuel pump relays, and both must be working for the fuel pump to operate properly.

The 2006 Lancer is part of the ninth generation (CS platform), which was produced from 2000 through 2007. This generation includes both the standard Lancer and the high-performance Lancer Evolution, and the relay locations differ slightly between these models. Understanding exactly where these relays are and how to test them can save you both time and money when diagnosing a no-start condition.

Key Facts About the Fuel Pump Relay

  1. The standard Lancer has two fuel pump relays inside the cabin fuse box: Fuel Pump Relay (1) and Fuel Pump Relay (2).
  2. The Lancer Evolution uses a similar layout with two relays, plus a third fuel pump relay (Relay 3) located at the right side of the firewall in the engine compartment.
  3. A 7.5-amp fuse in the interior fuse box protects the engine control unit and the fuel pump relay circuits.
  4. The main fuel pump fuse (15-amp) is found in the engine compartment fuse box.

Where to Find the Interior Fuse Box

The passenger compartment fuse box, also called the junction block, is located behind the coin storage pocket on the driver's side of the dashboard. To access it, open the driver's door and look at the end of the dashboard. You will need to pull the coin pocket straight out to reveal the fuse panel behind it. The fuse box cover has a diagram showing the position and amperage of each fuse and relay, but the labels can fade over time, so it is a good idea to cross-reference with the owner's manual if you have it.

Inside this fuse box, you will find fuse positions numbered 1 through 24, along with eight relay positions labeled R1 through R8. The two fuel pump relays are labeled R1 (Fuel Pump Relay 1) and R3 (Fuel Pump Relay 2), according to the relay layout diagram for the ninth-generation Lancer.

How the Fuel Pump Relay System Works

Understanding how the relay system operates helps you diagnose problems correctly. When you turn the ignition key to the ON position, the Engine Control Unit (ECU) energizes Fuel Pump Relay (2) for about one second to prime the fuel system. When you crank the engine, the ECU keeps this relay energized, and it also turns on Fuel Pump Relay (1). Both relays must be working for the fuel pump to run continuously.

Relay 1 receives power when the ignition switch is turned on. Relay 2 is controlled directly by the engine computer, which switches it on for that initial prime period and then again while the engine is cranking or running. If either relay fails, the fuel pump will not operate, and the engine will crank but never start.

The two relays are located in the relay group inside the dash fuse panel. The first relay sits in the bottom corner of the relay group, and the second one sits to the right with one blank space in between them. It is common for these relays to be reinstalled incorrectly after prior diagnostic work, so verify the positions carefully before replacing parts.

Testing the Fuel Pump Relay

Before you buy any replacement parts, test the relay to confirm it is actually defective. A relay is an electromagnetic switch, and you can test it with a digital multimeter. Here is a straightforward procedure:

Step 1: Remove the Relay

With the ignition off, locate the R1 and R3 relays in the interior fuse box and pull them straight out. They are standard automotive relays, and no special tools are needed for removal.

Step 2: Check for Continuity

Set your multimeter to the resistance (ohms) setting. Touch the probe leads to the two smaller terminals on the relay (the coil terminals). You should read a resistance value between 50 and 120 ohms, which indicates the coil is intact. If you read infinite resistance, the coil is open, and the relay is dead.

Step 3: Apply Power to the Coil

Use jumper wires to connect the coil terminals to a 12-volt battery. When power is applied, you should hear a distinct click as the internal switch closes. While power is applied, check continuity across the two larger terminals (the switch terminals). The reading should drop to near zero ohms. If there is no click or no continuity, the relay is faulty and needs replacement.

Checking the Fuel Pump Fuses

A blown fuse can mimic a failed relay, so test the fuses before condemning the relay. The standard Lancer uses two fuses that protect the fuel pump circuit. The first is fuse number 8 in the interior fuse box, rated at 7.5 amps, which protects the engine control unit and the fuel pump relay circuits. The second is fuse number 24 in the engine compartment fuse box, rated at 15 amps, which protects the fuel pump itself.

For the Lancer Evolution, the layout is slightly different. The Evolution uses fuse position 8 in the interior fuse box (7.5 amps) for the engine ECU and fuel pump relay circuits, and a dedicated 20-amp fuse in the engine compartment for the fuel pump and fuel gauge unit. There is also a dedicated fuse labeled "Fuse 15" rated at 20 amps in the engine compartment relay box for the fuel pump circuit on the Evolution model.

To check a fuse, pull it out and look at the metal strip inside. If the strip is broken or melted, the fuse is blown. You can also use a test light or multimeter to check for voltage at the fuse terminals with the ignition on.

Why the Fuel Pump Relay Fails

Fuel pump relays are electromechanical devices, and they wear out over time. The most common causes of relay failure include:

  1. Age and normal wear: The internal contacts arc slightly every time the relay switches, and over time this erodes the contact surfaces. After 15 to 20 years, this wear is significant enough to cause intermittent or complete failure.

  2. Excessive heat: The interior fuse box is not directly exposed to engine heat, but on hot summer days, the cabin temperature can get quite high. Repeated exposure to high temperatures can degrade the relay's internal components.

  3. Voltage spikes: A failing alternator or battery can produce voltage spikes that stress the relay coil and contacts, shortening the relay's service life.

  4. Moisture intrusion: If the windshield seal or door seals are leaking, moisture can get into the fuse box area and corrode relay terminals.

Lancer Evolution Differences

If you drive a 2006 Lancer Evolution, the fuel pump relay system is more complex than the standard Lancer. The Evolution uses not only the two relays inside the cabin fuse box but also a third relay called "Fuel Pump Relay 3." This relay is located at the right side of the firewall in the engine compartment. The Evolution also has a fuel pump resistor in the right rear of the engine compartment, which works with the pump to provide variable fuel pressure based on engine demand.

For the Evolution, the engine compartment fuse box has a 20-amp fuse in position 24 that protects the fuel pump relay 3, the fuel pump resistor, and the fuel pump with the fuel gauge unit. This fuse is in addition to the 7.5-amp fuse in the interior fuse box.

Step-by-Step Troubleshooting for a No-Start Condition

If your 2006 Lancer cranks but will not start, work through this checklist in order:

  1. Listen for the fuel pump prime: Turn the ignition key to the ON position without cranking. You should hear a faint hum from the rear of the car for about one second as the fuel pump primes. If you do not hear this, the fuel pump circuit may not be receiving power.

  2. Check the fuel pump fuses: Locate the 15-amp fuse (number 24) in the engine compartment fuse box and the 7.5-amp fuse (number 8) in the interior fuse box. Inspect both for continuity. Replace any blown fuses and retest.

  3. Test the relays: Pull out both fuel pump relays from the interior fuse box and test them with a multimeter as described above. If either relay fails the test, replace it.

  4. Listen for relay click: With the relays installed, have an assistant turn the ignition on while you hold your hand on the relay. You should feel and hear a click as the relay energizes. No click means the ECU is not commanding the relay, which could indicate a separate electrical issue.

  5. Check for power at the fuel pump: If the fuses and relays are all good, use a multimeter to check for voltage at the fuel pump connector in the rear of the vehicle. The pump is accessed through an access panel under the rear seat. If there is power but the pump does not run, the pump itself is defective.

What If the Relays Are Good but the Pump Still Does Not Run?

If the fuses and relays all test good, there are several other potential causes for a fuel pump that does not operate:

  • Defective fuel pump: The pump motor itself may have worn out. A fuel pump that is failing may draw excessive current, which can blow the fuse. Check the pump's resistance across its terminals; the reading should be within the manufacturer's specified range.

  • Activated impact sensor: Some vehicles have an inertia switch or impact sensor that cuts power to the fuel pump in the event of a crash. If this sensor was triggered for any reason, the pump will not run even with good fuses and relays.

  • Engine Control Unit problems: The ECU controls fuel pump relay 2. If the ECU has failed or if a sensor feeding the ECU is defective, the relay may never energize. This requires diagnostic equipment to test properly.

  • Wiring issues: Damaged or corroded wiring between the relay, fuse, and fuel pump can interrupt power delivery. Inspect the wiring harness under the rear seat and along the frame rails for damage.

Recommended Replacement Relays

When replacing the fuel pump relay, you do not need to purchase an OEM part from the dealership. Standard aftermarket relays with the same pin configuration and current rating work perfectly. Look for a relay rated for 12 volts with a minimum 30-amp contact rating. These are available at any auto parts store for a modest price.

KEMSO Fuel Pump Recommendation

If your testing confirms the fuel pump itself has failed, we recommend the KEMSO brand fuel pump for your replacement. KEMSO fuel pumps are built to high performance standards and are designed as OEM replacement parts, meaning they meet or exceed the original equipment specifications for fit, form, and function. Every KEMSO fuel pump comes with a lifetime warranty, so you can install it with confidence knowing that KEMSO stands behind its product for as long as you own your vehicle.

KEMSO offers a wide range of fuel pumps covering many popular makes and models, from BMW motorcycles and Subaru sedans to Kawasaki Jet Skis and Honda motorcycles, all priced at a competitive $79.98. To find the right KEMSO fuel pump for your 2006 Mitsubishi Lancer, visit their website at:

https://www.kemsoracing.com/

Browse their selection, check the fitment guide, and order your replacement fuel pump today. With KEMSO's lifetime warranty and high-performance construction, you can get your Lancer back on the road reliably.

Final Thoughts

Knowing where the fuel pump relay is located on your 2006 Mitsubishi Lancer and how to test it can save you a significant amount of money in diagnostic fees. The relay is easy to access, easy to test, and inexpensive to replace. Always start with the simplest and most likely causes—bad fuses and failed relays—before moving on to more expensive components like the fuel pump or ECU. And when the pump does need replacement, choose a KEMSO fuel pump for reliable, long-lasting performance backed by a lifetime warranty.

For more information on KEMSO fuel pumps and to view their full product catalog, visit https://www.kemsoracing.com/ .


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