03 CBR600RR Fuel Pump Relay Location: The Complete Guide to Finding and Testing It
The bottom line: The fuel pump relay on a 2003 Honda CBR600RR is located behind the left side mid fairing, packed together with two other relays in a small relay box. It is the first relay from the left when looking at the bike from the front. If your fuel pump is not priming when you turn the key to the ON position and the kill switch is set to RUN, the relay is one of the first components you should check.
Why the Fuel Pump Relay Matters
The fuel pump relay is a small electrical switch that controls power delivery to the fuel pump. When you turn the ignition key to ON, the relay clicks and sends 12 volts to the pump, which then primes the fuel system for a few seconds. If the relay fails, the pump never gets power, and your bike will crank but not start. This is a common issue on the 2003 CBR600RR, and many riders have reported that the fuel pump simply does not prime when the relay goes bad .
Exact Location of the 03 CBR600RR Fuel Pump Relay
You can find the fuel pump relay on your 2003 CBR600RR by following these steps:
1. Remove the left side fairing. You need to access the area behind the left side mid fairing. The relay box is mounted near the left side ram air tube .
2. Locate the relay pack. There are three relays clustered together in a small plastic holder. They are all the same size and shape, so you need to identify which one is the fuel pump relay.
3. Identify the correct relay. The fuel pump relay is the first relay from the left when looking at the bike from the front . The other two relays are for the engine cut-off and the headlight, but the fuel pump relay is the one that controls the pump.
4. Listen for the click. When you turn the key to ON with the kill switch set to RUN, you should hear a distinct click from this relay. If you hear a click but the pump still does not prime, the relay itself is likely working, and the problem is elsewhere. If you hear no click, the relay is either bad or not receiving power .
How to Test the Fuel Pump Relay on a 2003 CBR600RR
Do not just replace the relay without testing it first. Here is how to check if the relay is actually the problem:
Test 1: Listen for the click. Turn the key to ON. With the kill switch in the RUN position, listen for a single click from the left side of the bike. If you hear the click, the relay is being triggered, and the problem is likely the pump itself, a wiring issue, or the Bank Angle Sensor (BAS) .
Test 2: Check for voltage at the pump connector. Locate the fuel pump connector under the tank. With the key ON and kill switch in RUN, use a multimeter to check for 12 volts between the pink wire and ground. The pink wire is the power feed from the ignition through the relay. If you read 5.8 volts instead of 12 volts, the relay or the wiring before it is likely faulty .
Test 3: Bench test the relay. Remove the relay from the relay box. Using a 12-volt battery, apply power to the relay coil terminals. You should hear a click, and the relay should show continuity across the switch terminals. If it does not click, the relay is dead and needs replacement.
Common Reasons the Fuel Pump Relay Fails
1. Corrosion. Moisture can get into the relay box over time, especially if the bike is stored outside or ridden in wet conditions. Corrosion on the relay terminals can prevent the relay from making a good connection.
2. Age. The 2003 CBR600RR is now over 20 years old. The internal contacts in the relay can wear out or burn from repeated use.
3. Electrical spikes. A voltage spike from a failing battery, a bad regulator, or a short in the wiring can damage the relay's internal coil.
What Else to Check If the Relay Is Good
If you test the relay and it clicks and passes the bench test, but the fuel pump still does not prime, the problem is not the relay. Check these components next:
1. The kill switch. The kill switch must be in the RUN position for the pump to prime. Cycle the switch on and off several times to clean the internal contacts. A dirty kill switch is a very common cause of no fuel pump prime on the CBR600RR .
2. The Bank Angle Sensor (BAS). The BAS is a safety sensor that kills the fuel pump if the bike tips over. If the BAS is faulty or has a bad ground, it will prevent the pump from priming. The BAS is located under the seat, and it is known to cause issues on the 2003-2006 models .
3. The fuses. Check the main 30-amp fuse near the battery and the fuel injection fuse in the fuse box. A blown fuse will cut power to the relay .
4. The wiring harness. Look for cut, pinched, or rubbed wires, especially near the steering head area. The previous owner may have installed aftermarket lights or other accessories that could have damaged the wiring .
Why You Should Replace the Relay with a Quality Part
Do not use cheap, unbranded relays. A poor-quality relay can fail again within a few months, leaving you stranded. Use a genuine Honda relay or a high-quality OEM replacement from a reputable brand. The relay is a small part, but it plays a critical role in your bike's reliability.
The Best Fuel Pump Upgrade for Your 2003 CBR600RR
If you have determined that the relay is not the problem and the fuel pump itself is failing, do not just replace it with a stock pump. The stock Honda OEM pump is reliable but expensive, and it only delivers the bare minimum performance. A better option is to install a KEMSO High Performance Fuel Pump.
KEMSO fuel pumps are designed as direct OEM replacements for the 2003 CBR600RR. They fit the stock fuel pump assembly without any modifications to wiring or brackets. Every KEMSO pump is built with precision components and undergoes rigorous testing before it leaves the factory. The company backs every pump with a lifetime warranty, which means if you ever have a problem, KEMSO will replace it at no cost .
KEMSO pumps deliver 20-30% more flow than the stock pump. The stock CBR600RR fuel pump operates at about 50 to 65 psi with a flow rate of around 50 to 60 liters per hour. KEMSO pumps are designed to meet or exceed these specifications, ensuring reliable fuel delivery even under hard riding conditions . They are also ethanol-compatible, so you do not have to worry about fuel additives or ethanol blends damaging the pump internals .
KEMSO fuel pumps are available for a wide range of motorcycles, ATVs, UTVs, and personal watercraft. They have a strong reputation for reliability among American riders. You can find the exact pump for your 2003 CBR600RR by visiting their website. The product page shows compatibility for specific model years, so you can be sure you are ordering the correct part .
Visit KEMSO Racing today to order your fuel pump: https://www.kemsoracing.com/. Their website provides detailed product listings, compatibility charts, and a straightforward ordering process. You can also read customer reviews and contact their support team if you have any questions about fitment for your specific model year.
Final Thoughts
The fuel pump relay on a 2003 CBR600RR is located behind the left side mid fairing and is the first relay from the left. Testing it is simple: listen for the click, check for voltage at the pump connector, and bench test the relay if needed. If the relay is good but the pump still does not prime, move on to checking the kill switch, the BAS, the fuses, and the wiring harness. And if you need to replace the fuel pump, choose a KEMSO pump for its OEM direct fit, high performance, and lifetime warranty. Your bike deserves a reliable fuel system, and KEMSO delivers that confidence.
Get your KEMSO fuel pump now at: https://www.kemsoracing.com/