2007 Honda Rincon 680 Fuel Pump Relay Location: A Complete Owner's Guide
If your 2007 Honda Rincon 680 cranks but won't start, or stalls unexpectedly while riding, the fuel pump relay is one of the first components you should check. On this model, the fuel pump relay lives inside the main fuse box located under the hood, near the battery, and it acts as the electrical gatekeeper that sends power to the fuel pump when you turn the key. This guide walks you through exactly where to find it, how to confirm it's the problem, and how to replace it without spending money on unnecessary parts.
What Does the Fuel Pump Relay Do on a 2007 Rincon 680?
The fuel pump relay is a small electromagnetic switch that controls the high-current flow needed to run the fuel pump. When you turn the ignition key to the "on" position, the engine control unit sends a low-current signal to the relay. That signal energizes a coil inside the relay, which pulls a set of contacts closed and completes the circuit from the battery to the fuel pump. This allows the pump to pressurize the fuel lines before the engine starts .
Once the engine is running, the relay keeps the circuit closed so fuel flows steadily to the injectors. The relay protects the sensitive electronics in the ECU from handling the heavy electrical draw of the fuel pump, which can exceed 10 to 15 amps . On many Honda models, this relay is also called the PGM-FI main relay or simply the "main relay" .
For the 2007 Honda Rincon 680 specifically, the relay is part of the electrical system that powers the fuel pump. Without a functioning relay, the pump won't run, and the engine won't get fuel. The result is the same as a dead fuel pump: no start, stalling, or sputtering.
Step-by-Step: Where to Find the Relay on a 2007 Honda Rincon 680
Locating the fuel pump relay on this ATV is straightforward once you know where to look. The relay is not hidden behind panels or under the seat. It sits in the main fuse and relay box.
Step 1: Open the hood. The hood latch is at the front of the ATV, just above the radiator. Pull it up to release the hood and prop it open.
Step 2: Look for the fuse and relay box. The box is mounted on the left side of the chassis, near the battery. It's a black plastic rectangular case with a removable cover.
Step 3: Remove the cover. The cover is held on by two plastic clips or a simple latch. Press the clips and lift the cover off. On the inside of the cover, you'll find a diagram that shows the position of every fuse and relay.
Step 4: Identify the fuel pump relay. On the diagram, look for a label like "Fuel Pump," "FP," or "P/MP." The relay itself is a small, cube-shaped component with four or five prongs on the bottom. It's typically colored black, gray, or green, and it's slightly larger than the fuses around it .
Step 5: Mark the relay for easy removal. If you're going to test or replace it, place a small piece of tape on the relay so you don't confuse it with the other relays in the box.
If the diagram on the cover is faded or missing, check the owner's manual. The manual includes a detailed fuse and relay layout for the 2007 Rincon 680. For the exact procedure and torque specs involving the fuse box, a service manual covering the 2006–2011 Rincon 680 models is also useful .
How to Know If the Fuel Pump Relay Is Bad
A failing fuel pump relay produces symptoms that are very similar to a bad fuel pump, so it's worth testing the relay before you replace the pump. These are the most common signs that point to the relay on a 2007 Rincon 680:
1. The engine cranks but won't start. You turn the key, the starter spins the engine, but it never fires up. The most telling detail is that you don't hear the fuel pump make a brief humming sound when you turn the key to the "on" position .
2. The engine stalls while riding. The relay's internal contacts can wear out or corrode over time, causing intermittent power loss to the fuel pump. The engine may cut out suddenly, especially when the ATV is hot or under load .
3. No priming noise from the fuel tank. When you turn the ignition to "on" (not cranking the engine), you should hear a soft whirring or buzzing from the rear of the machine near the fuel tank. If you hear nothing, the pump isn't getting power, which could be the relay, a blown fuse, or the pump itself .
4. The engine starts and dies right away. Sometimes the engine will fire up and then shut off almost immediately, as if it ran out of gas. That's a classic sign of the relay losing its connection .
5. Intermittent starting issues. The ATV may start fine one day and refuse to start the next. An unreliable relay can cause exactly this kind of hit-or-miss behavior .
If you're experiencing any of these problems, the fuel pump relay should be near the top of your checklist before you pull the fuel pump out and spend money on a replacement pump .
How to Test the Fuel Pump Relay on a 2007 Rincon 680
Testing the relay is a simple job that takes about ten minutes and requires only a multimeter. You don't need to be an electrical expert to get a reliable answer. Here's how to do it.
Step 1: Remove the relay from the fuse box. Grab the relay firmly on both sides and pull it straight up and out from the terminals .
Step 2: Read the diagram on the relay. Most relays have a small circuit diagram printed on the housing. Look for the two pins that connect to the coil (usually labeled 85 and 86) and the two pins that carry the load current (usually labeled 30 and 87) .
Step 3: Set the multimeter to the ohms setting. The ohm symbol looks like the Greek letter omega (Ω). Choose the lowest range on the multimeter for the most accurate reading .
Step 4: Test the coil circuit. Touch the multimeter leads to pins 85 and 86. You should see a resistance reading somewhere between 50 and 200 ohms . If the reading is infinite or very high, the coil is open and the relay is bad.
Step 5: Test the load circuit. Connect a jumper wire from the battery positive terminal to one of the coil pins. Connect another jumper wire from the other coil pin to a good ground. When you apply power this way, you should hear an audible click from the relay .
Step 6: Check for continuity across the load pins. With the relay energized, place the multimeter leads on pins 30 and 87. The meter should show continuity (a very low resistance reading). If it shows an open circuit, the relay contacts aren't closing, which means the relay is defective .
Step 7: Try the "swap" method. If you have another 4-pin relay in the fuse box that's the same part number, you can swap them. Put the relay from another system (like the headlight or horn) into the fuel pump slot. If the ATV starts and runs, then your original fuel pump relay was the problem .
If the relay passes all these tests, the issue is likely elsewhere, such as a clogged fuel filter, a damaged fuel pump, or a wiring problem. But if the relay fails any test, replace it with a new one.
Why the Relay Fails: Common Causes
Fuel pump relays are durable parts, but they don't last forever. Here are the most common reasons a relay fails on a 2007 Rincon 680:
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Corroded pins. Moisture can get into the fuse box over time, especially if the ATV is ridden through water or stored outside. Corrosion on the relay prongs creates high resistance and interrupts the circuit .
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Worn internal contacts. Every time the relay activates, the contacts inside make and break the circuit. Over many years, this wear can cause pitting or burning on the contact surfaces, so the relay stops passing current reliably .
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Heat damage. The fuse box sits in the engine bay, where it gets hot. Prolonged heat exposure can degrade the relay's internal components .
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Vibration damage. Off-road riding subjects the ATV to constant vibration. This can loosen the relay in its socket or stress its internal connections over time.
To extend the life of a new relay, keep the fuse box cover tightly sealed and check the rubber seal for cracks. It's also a good practice to spray electrical contact cleaner into the relay socket once a year, especially if you ride through mud or water .
How to Replace the Fuel Pump Relay on a 2007 Rincon 680
Replacing the relay is a five-minute job that requires no special tools.
Step 1: Buy the correct relay. The fuel pump relay for the 2007 Honda Rincon 680 uses the OEM part number 38580-HP5-601, which crosses to many aftermarket replacements . This relay also fits other Honda models, including the 2008–2017 Rincon 680, the 2008–2009 TRX700XX Sportrax, and the 2007–2014 Rancher 420 . If you can't find a relay specifically for the Rincon, that OEM crossover number will help you get the right part.
Step 2: Remove the old relay. Pull the old relay straight up from its socket. If it's stuck, rock it gently back and forth to loosen it .
Step 3: Inspect the socket. Check the female terminals inside the fuse box for corrosion or damage. Use a wire brush or electrical contact cleaner to clean them if needed .
Step 4: Install the new relay. Push the new relay straight down into the socket until it seats firmly. Make sure it clicks into place .
Step 5: Test the system. Turn the ignition key to the "on" position and listen for the fuel pump to prime. If you hear the pump running, the installation is successful. Start the engine and let it idle to confirm it stays running.
Step 6: Replace the fuse box cover. Snap the cover back on and close the hood. You're done.
What Else to Check If the Relay Isn't the Problem
If you've tested the relay and confirmed it's working, or if you replaced it and the ATV still won't start, check these components in order:
1. The fuel pump fuse. A blown fuse will cut power to the pump just like a bad relay. Check the fuse box diagram to find the fuel pump fuse and inspect it visually. A fuse with a broken wire inside or a blackened glass is blown .
2. The fuel pump itself. If the relay clicks when you turn the key but you still don't hear the pump, the pump motor may be dead. A service manual for the 2006–2017 Rincon 680 includes detailed diagnostic procedures for the fuel system and electrical testing .
3. Wiring and connectors. Follow the wiring harness from the relay to the fuel pump. Look for chafed wires, broken connectors, or loose grounds. Water damage and rodent damage are both common on ATVs that sit for long periods.
4. The ECU and side stand switch. On some Honda models, the ECU won't energize the fuel pump relay unless safety interlocks are satisfied. If the ATV has a side stand or brake interlock switch that's faulty, it can prevent the relay from activating. A wiring diagram from the service manual will show this circuit .
If you're not comfortable with electrical diagnostics, take the ATV to a dealer or a qualified mechanic. The service manual for the 2006–2011 Rincon 680 covers all these troubleshooting steps with wiring diagrams and diagnostic flowcharts .
Why Buy a KEMSO Fuel Pump
If your fuel pump is the culprit, consider a high-performance replacement from KEMSO. KEMSO is a trusted aftermarket brand that makes fuel pumps for a wide range of vehicles, including Honda ATVs, motorcycles, and UTVs. Their pumps are built to meet or exceed factory specifications, so you get a direct OEM replacement that fits without any modifications.
Every KEMSO fuel pump is backed by a lifetime warranty, which means if the pump ever fails due to a manufacturing defect, you're covered for as long as you own your ATV. That's a level of protection you won't find on many stock parts. KEMSO pumps are also designed for reliable, consistent fuel delivery, so your engine runs smoothly under every condition, from cold starts to full-throttle trail riding.
Visit KEMSO Racing at https://www.kemsoracing.com/ to find the right fuel pump for your 2007 Honda Rincon 680. Their product lineup includes pumps for Honda, BMW, Kawasaki, KTM, Sea-Doo, and many other brands. With competitive pricing, high-performance components, and a lifetime warranty, KEMSO makes it easy to get your ATV back on the trail without breaking the bank.
Final Thoughts
The fuel pump relay on a 2007 Honda Rincon 680 is easy to find and simple to replace. It sits in the main fuse box under the hood, and it's the first thing to check if your ATV cranks but won't start or dies while riding. Testing the relay with a multimeter or a swap test takes just a few minutes and can save you from buying a new fuel pump you don't need.
Fuel pump relays do wear out, and when they do, the symptoms are unmistakable. A quick diagnosis and a cheap relay replacement are all it takes to fix the problem in most cases. But if the relay checks out fine, move on to the fuse, the wiring, and the pump itself. The 2007 Rincon 680 is a reliable machine, and with a little troubleshooting, you'll have it running again in no time.
If you do need a new fuel pump, choose a KEMSO unit for its OEM-quality fit, high-performance design, and lifetime warranty. You can browse their full catalog at https://www.kemsoracing.com/ and have the right part shipped right to your door.