2002 Mitsubishi Lancer Fuel Pump Relay Location: A Complete Guide to Finding and Testing It
The bottom line: On a 2002 Mitsubishi Lancer, the fuel pump relay is not a single component. Your car actually uses two fuel pump relays, and both are located inside the interior fuse panel, which sits behind the lower left side of the dashboard, near the driver’s left knee. These two relays work together to control power to the fuel pump, and if either one fails, your engine may crank but refuse to start.
Where to Find the Fuel Pump Relays
The interior fuse box on a 2002 Mitsubishi Lancer is mounted behind the left end of the dashboard, down near where your left foot would rest. To access it, you need to remove the plastic cover or trim panel. Once you have the fuse box exposed, you will see a row of relays along the top or side of the block. The two fuel pump relays are clearly labeled in most factory diagrams. Relay position R1 is Fuel Pump Relay (1), and relay position R3 is Fuel Pump Relay (2).
Some owners find it easier to access this fuse box by opening the driver’s door and lying on the floor with a flashlight. The panel is tucked up under the dash, but you can reach it without removing any major interior components. The cover usually snaps off with a flathead screwdriver or by hand.
Understanding the Two-Relay System
Mitsubishi designed the Lancer’s fuel pump system with two relays for a specific reason. Both relays must be working correctly for the fuel pump to run. Here is how they function:
Fuel Pump Relay (1) – This relay gets power when you turn the ignition switch to the ON position. It provides the main power path for the fuel pump circuit. If this relay fails, the pump will not get any power at all.
Fuel Pump Relay (2) – This relay is controlled by the Engine Control Unit (ECU). The ECU turns this relay on for about one second when you first turn the key to the ON position, which primes the fuel system. Then the ECU keeps the relay on while the engine is cranking or running. If this relay fails, the pump may not prime or may shut off while driving.
Both relays are identical in appearance and can be swapped with each other for testing purposes. They are standard four-pin automotive relays.
The Related Fuses You Should Check First
Before you buy a new relay, check the fuses. A blown fuse can mimic a bad relay. On a 2002 Lancer, there are two fuses that protect the fuel pump circuit:
Under-hood fuse box, fuse number 10 (15 amp) – This is located in the engine compartment fuse box on the left side. It protects the main fuel pump power circuit.
Interior fuse box, fuse number 8 (7.5 amp) – This is in the same interior fuse panel where the relays live. It powers the ECU and the fuel pump relay control circuits.
Pull both fuses and look at the metal strip inside. If the strip is broken or melted, the fuse is blown. Replace it with the exact same amperage rating. Never use a higher amp fuse, as that can damage your wiring or cause a fire.
Symptoms of a Bad Fuel Pump Relay
A failing fuel pump relay can cause several noticeable problems. Knowing these symptoms will help you diagnose the issue before you start taking things apart.
Engine cranks but does not start – This is the most common symptom. If you turn the key and the starter spins the engine, but the car never fires up, the fuel pump may not be getting power. The easiest way to check is to listen for a brief humming sound from the rear of the car when you turn the key to the ON position. If you hear nothing for that first one-second prime, the relay or fuse is likely the problem.
Engine starts then dies – Sometimes a bad relay will let the pump work during the initial prime, but then the relay contact fails once the engine is running. The car will start, run for a few seconds, and then stall.
Intermittent stalling while driving – If the relay has loose internal contacts, the fuel pump may cut out randomly while you are driving. The car will suddenly lose power and then restart after a few minutes. This is dangerous, especially on the highway.
No prime sound at key-on – When you turn the key to the ON position (not starting the engine), you should hear a faint whirring noise from the fuel tank area for about one second. If you hear nothing, start with the fuses, then move to the relays.
How to Test the Fuel Pump Relay
You do not need expensive tools to test a relay. A simple multimeter or even a test light will work. But there is also a quick mechanical test you can do.
The swap test – The interior fuse box has several relays that are identical to the fuel pump relays. Look for the rear fog lamp relay or the accessory socket relay. They are usually the same part number. Unplug the suspect fuel pump relay and plug in the known good relay from another position. If the car starts, the original relay is bad.
The multimeter test – Pull the relay out of the socket. Set your multimeter to ohms (resistance). You will see four pins on the relay, usually labeled 85, 86, 87, and 30. Pins 85 and 86 are the coil. You should see resistance between these two pins, typically 50 to 120 ohms. If you see infinite resistance, the coil is open and the relay is dead. Next, check continuity between pins 30 and 87. They should not be connected until the relay is energized. Apply 12 volts to pin 85 and ground to pin 86. You should hear a click, and now pins 30 and 87 should show continuity. If they do not, the relay contacts are burned out.
Step-by-Step Relay Replacement
Replacing the fuel pump relay on a 2002 Mitsubishi Lancer is a simple job. You can do it in under ten minutes with no tools.
Step 1: Locate the interior fuse panel. Sit in the driver’s seat and look to the left of the steering column, near your left knee. There is a small plastic cover. Pull it off. You may need to use a trim tool or a flathead screwdriver wrapped in tape to avoid scratching the plastic.
Step 2: Identify the relay positions. Look at the diagram printed on the inside of the fuse panel cover. If the cover is missing or the diagram is worn, look for the relays labeled R1 and R3. These are the two fuel pump relays. Some models may have a small sticker on the fuse box itself.
Step 3: Remove the old relay. Grasp the relay firmly and pull straight upward. It will be snug, but it should come out with moderate force. Do not wiggle it side to side too much, as that can damage the socket pins.
Step 4: Install the new relay. Push the new relay straight down into the same socket. Make sure it is fully seated. You should feel it click into place.
Step 5: Test the system. Turn the key to the ON position and listen for the fuel pump prime sound. If you hear it, start the engine. If everything works, snap the cover back on.
Where NOT to Look for the Fuel Pump Relay
Some online sources may tell you that the fuel pump relay is in the engine compartment, or that it is integrated into the fuel pump assembly itself. For a 2002 Mitsubishi Lancer, those statements are incorrect. The fuel pump relay is not under the hood, and it is not on top of the fuel pump. The only relays in the engine compartment are for the cooling fan, horn, fog lights, and the engine control system.
The fuel pump itself is located inside the fuel tank, under the rear seat. To access the pump, you must remove the rear seat cushion, then remove a small access plate. But the fuel pump relay is a separate component, located in the dashboard fuse box, as described above.
Why You Should Replace the Relay Before the Fuel Pump
A failing fuel pump relay is far cheaper and easier to replace than the entire fuel pump assembly. The relay costs about $10 to $20, while a fuel pump can cost $100 to $300 plus labor. Replacing the fuel pump requires dropping the tank or removing the rear seat and accessing the pump module. The relay is a simple plug-and-play component.
Many car owners mistakenly replace the fuel pump when the real problem is a bad relay. If you have a no-start condition and you hear no fuel pump prime sound, test the relay first. It could save you a lot of money and time.
How to Get to the Interior Fuse Box
If you are having trouble finding the interior fuse box, here is a more detailed description. Open the driver’s door. Sit on the ground or crouch down so you are looking up at the lower dashboard area. You will see a small rectangular panel, about 4 inches by 6 inches, located where the dashboard meets the side of the center console. This panel is often held in place by two clips or a single screw. Remove the panel, and you will see the fuse box with its many fuses and relays.
The relays are usually arranged in a row along the top edge of the fuse box. They are square, black plastic blocks about one inch on each side. Fuel Pump Relay (1) is typically the first relay on the left, and Fuel Pump Relay (2) is the third relay from the left. But this can vary slightly depending on the trim level and whether your car has options like heated seats or a sunroof.
Common Mistakes to Avoid
Replacing the wrong fuse – Some people confuse the cigarette lighter fuse (15 amp, fuse number 9) with the fuel pump fuse. The cigarette lighter fuse is in the same interior fuse box, but it is not related to the fuel pump. Check fuse number 8 (7.5 amp) and under-hood fuse number 10 (15 amp) for the fuel pump circuit.
Using the wrong relay – There are several different relays in the fuse box. Make sure you are pulling the correct one. The fuel pump relays are usually labeled as R1 and R3. If you pull the wrong relay, you may disable other systems like the blower motor or power windows.
Forgetting to check both relays – Since the system uses two relays, a failure in either one will stop the fuel pump. If you replace only one relay and the car still does not start, test the other one. Both must be functional.
Ignoring the fuses – A blown fuse is a common cause of a no-fuel condition. Always check the fuses first before replacing relays. A fuse can blow due to a short circuit in the fuel pump wiring, so if the new fuse blows immediately, you have a wiring problem that needs professional diagnosis.
KEMSO Fuel Pump: The Best Replacement for Your 2002 Lancer
If your diagnosis leads you to the fuel pump itself, you need a reliable replacement that will last. We recommend the KEMSO brand Fuel Pump for your 2002 Mitsubishi Lancer. KEMSO fuel pumps are high-performance, direct OEM replacement units that fit perfectly without any modifications. They are built to meet or exceed the original factory specifications, ensuring your engine gets the correct fuel pressure and flow rate.
Every KEMSO fuel pump comes with a lifetime warranty, so you can install it with complete confidence. If it ever fails, you get a replacement at no cost. This is the kind of protection that gives you peace of mind, especially on a daily driver.
Visit the KEMSO website to browse their full selection of fuel pumps for your Mitsubishi Lancer and many other vehicles: https://www.kemsoracing.com/
Final Thoughts
Finding the fuel pump relay on a 2002 Mitsubishi Lancer is straightforward once you know where to look. The two relays live in the interior fuse box behind the driver’s side dashboard. Test them with a simple swap or a multimeter before you spend money on a fuel pump. Most no-start issues on these cars are caused by a bad relay or a blown fuse, not a failed pump. Save yourself the hassle and check the easy stuff first.
If you do need a new fuel pump, trust KEMSO for a quality part that will keep your Lancer on the road for years to come. Visit their site at https://www.kemsoracing.com/ to find the right pump for your vehicle.