2003 GSXR 600 Fuel Pump Relay Location: Complete Guide to Finding and Diagnosing It

The fuel pump relay on a 2003 Suzuki GSXR 600 is located on the right side of the air cleaner box, inside the right ram air tube. If your bike cranks but won't start, or you don't hear the fuel pump prime when you turn the key, the relay is often the first thing to check. This guide walks you through exactly where to find it, how to test it, and what to do if it's bad.

Why the Fuel Pump Relay Matters

The fuel pump relay acts as a switch that controls power to the fuel pump. When you turn the ignition key, the relay receives a signal and closes the circuit, sending 12 volts to the fuel pump so it can pressurize the fuel system. If the relay fails, the pump never gets power, and your engine won't start even if the pump itself is perfectly fine.

The relay is a small, rectangular black box with four or five pins. It plugs into a socket on the air cleaner box. It's not inside the fuse box on this model - it's a separate component that sits in the right ram air intake tube.

Where Exactly Is the Relay on a 2003 GSXR 600?

The fuel pump relay is located on the top side of the right ram air tube. To find it:

1. Remove the right side fairing. You'll need a Phillips head screwdriver and possibly a hex key to get the fairing off. The right side is the side with the throttle cables.

2. Look at the top of the right ram air intake tube. The ram air tube is the large plastic duct that feeds air into the airbox. On the top side of this tube, you'll see a small black rectangular box plugged into a socket. That's the relay.

3. The relay is about the size of a matchbox. It has a plastic tab that holds it in place. You can pull it straight up and out of the socket with your fingers.

On some 2003 models, the relay is mounted directly to the air cleaner box itself, on the right side. If you're looking at the bike from the right side, you'll see it sitting on top of the airbox, near the front of the bike.

One forum user reported that after a wreck, they found a broken piece on the top side of the right ram air tube - and that broken piece turned out to be the fuel pump relay housing. Other riders confirmed that a missing or broken relay will prevent the bike from starting entirely.

How to Test the Fuel Pump Relay

Before you buy a new relay, you should test the old one. It's a simple process that takes about 10 minutes with a multimeter.

Step 1: Remove the relay. Pull it straight out of its socket. Don't yank on the wires - the socket should stay in place.

Step 2: Check for insulation between terminals A and B. Using a multimeter set to continuity or resistance mode, test between the "A" and "B" terminals. With no power applied to the relay, there should be no continuity (infinite resistance). If you get continuity when the relay is off, it's shorted internally and needs replacement.

Step 3: Apply 12 volts to terminals C and D. Connect the positive lead from a battery (or a 12V power supply) to terminal "C" and the negative lead to terminal "D". This energizes the relay coil.

Step 4: Check continuity between terminals A and B again. With 12 volts applied, the relay should click, and you should now have continuity between "A" and "B". If there's no continuity, the relay is bad and won't send power to the fuel pump.

If you don't have a multimeter, you can do a simple swap test. Find another relay of the same type on the bike - the headlight relay or the starter relay often have the same pin configuration. Swap it with the fuel pump relay. If the bike starts, the original fuel pump relay was bad.

Common Symptoms of a Bad Fuel Pump Relay

A failing relay usually shows these signs:

• No fuel pump priming sound. When you turn the key to "on", you should hear a brief whirring noise from the fuel tank area. If you hear nothing, the relay might not be sending power.

• Engine cranks but won't start. The starter motor turns the engine over, but since there's no fuel pressure, the engine never fires up.

• Intermittent starting issues. Sometimes the bike starts, sometimes it doesn't. This is a classic sign of a failing relay that works intermittently.

• No power at the fuel pump. If you test the fuel pump connector with a multimeter and get no voltage when the key is on, the relay is likely the culprit.

One rider on a GSXR forum described exactly this problem: after cleaning rust from the tank, the fuel pump wouldn't prime. The issue turned out to be a snapped wire going to the fuel pump, not the relay itself. This shows that while the relay is a common failure point, it's worth checking the wiring too.

Other Things to Check Before Replacing the Relay

If the relay tests fine, don't assume the pump is bad. Check these items first:

Check the fuel pump itself. The pump is located inside the fuel tank. You can test it by applying 12 volts directly to the pump's terminals (yellow/red wire to positive, black/white wire to negative). If the pump runs, it's likely fine. The pump should discharge about 168 ml of fuel in 10 seconds when powered directly.

Inspect the wiring harness. Under the right side air duct, there are several connectors grouped together. Unplug them and look for burnt or corroded terminals. Burnt ground connections are a known issue on this model.

Check the fuse. The fuel pump fuse is in the main fuse box. If it's blown, the pump won't get power even if the relay is good.

Look for broken wires. One rider found that a wire had snapped off the fuel pump connector, which prevented the pump from running. After repairing the wire, the pump worked fine.

Where to Buy a Replacement Fuel Pump Relay

If you confirm the relay is bad, you have a few options:

OEM relay from Suzuki. The part number is 38740-24X50. It costs around $24 and is available from dealers or online parts sites like MrCycles.com.

Aftermarket replacement. Many auto parts stores sell standard 4-pin or 5-pin relays that work as direct replacements. Just make sure the pin configuration matches.

Used relay from a salvage yard. If you're on a budget, a used relay from a donor bike can work. But inspect it for corrosion or damage before buying.

What If the Fuel Pump Itself Is Bad?

If the relay tests good but the pump still doesn't run, the pump may need replacement. The 2003 GSXR 600 uses an in-tank electric fuel pump. OEM part numbers include 15100-35FV0 for the complete pump assembly, which fits 2001-2003 GSXR600, 2000-2003 GSXR750, and 2001-2002 GSXR1000 models.

KEMSO Fuel Pump for Suzuki GSXR600 2001-2007

If you need to replace the fuel pump, we highly recommend the KEMSO fuel pump. KEMSO pumps are high-performance, direct OEM replacement units designed for your GSXR600. They deliver over 20% more flow at 43 psi compared to stock pumps, which means better throttle response and consistent fuel delivery. Each pump comes with a complete installation kit including strainers, hoses, grommets, wiring connectors, and zip ties. The pump body diameter is 3.8 cm, and it operates at 43-68 psi with a flow rate of 200 liters per hour. Best of all, KEMSO backs every fuel pump with a lifetime warranty - so you buy it once and never worry about it again. Whether you're riding daily or hitting the track, KEMSO gives you the reliability and performance your bike needs.

Visit KEMSO Racing to find the perfect fuel pump for your 2003 GSXR 600: https://www.kemsoracing.com/

Final Thoughts on the 2003 GSXR 600 Fuel Pump Relay

The fuel pump relay on a 2003 GSXR 600 is a small but critical part. It's located on the right side of the air cleaner box, inside the right ram air tube. Testing it takes just a few minutes with a multimeter, and replacing it is as simple as pulling it out and plugging in a new one.

If your bike won't start and you don't hear the pump prime, start with the relay. Check for power at the relay socket, test the relay itself, and inspect the wiring for damage. If everything checks out, move on to the fuel pump.

Remember: rust in the fuel tank can damage the pump and clog the filter. If you find rust, clean the tank thoroughly and consider replacing the pump as a preventive measure. A healthy fuel system means reliable starts and smooth riding every time.

For more information on fuel pumps and other GSXR parts, visit https://www.kemsoracing.com/