2000 Lexus LX470 Fuel Pump Relay Location: A Complete Guide to Diagnosis, Testing, and Replacement

The bottom line: The fuel pump relay on your 2000 Lexus LX470 is located in the engine compartment fuse box, specifically in the under-hood relay box on the driver's side near the battery. If your LX470 cranks but won't start, or starts briefly then dies, a faulty fuel pump relay is one of the most common causes, and finding and testing it is the first step in getting your luxury SUV back on the road.

Understanding the Fuel Pump Relay in Your 2000 Lexus LX470

The fuel pump relay is a small electrical switch that controls power to the fuel pump. When you turn the key to the "ON" position, the relay closes and sends 12 volts to the fuel pump, pressurizing the fuel system before the engine starts. On the 2000 Lexus LX470, this relay is a critical component in the starting and running circuit.

A failing relay can cause a variety of frustrating symptoms. The most common sign is that the engine cranks over normally but never fires up. You might also notice that the vehicle starts and then stalls after a few seconds, or that it runs rough and hesitates under load. In some cases, the Check Engine Light may illuminate, often with codes related to fuel system pressure or circuit malfunctions.

Where Exactly Is the Fuel Pump Relay Located?

On the 2000 Lexus LX470, the fuel pump relay is located in the engine compartment relay box (also called the under-hood fuse and relay center). This box is situated on the driver's side of the engine bay, right next to the battery.

Here is how to find it step by step:

  1. Open the hood and secure it with the prop rod.
  2. Look at the left side (driver's side) of the engine compartment. You will see a large black plastic rectangular box directly next to the battery.
  3. Remove the cover of this relay box. Most covers have a small tab or clip on each side. Press these tabs and lift the cover straight up.
  4. Look inside the box. The fuel pump relay is typically a medium-sized cube relay, usually marked with a diagram on the inside of the cover. On the 2000 Lexus LX470, the relay is often labeled as "FUEL PUMP" or "FUEL," but if not, you can identify it by its position and wiring. The relay itself is usually a standard 4-pin or 5-pin relay, black or dark gray in color.

How to Test the Fuel Pump Relay

Before you replace the relay, it is smart to test it. A relay can fail in two ways: it can either not close (no power to the pump) or it can stick closed (pump runs constantly). Here is a simple test you can do with a multimeter:

The Click Test:

  1. Have a helper sit in the driver's seat and turn the key to the "ON" position (do not start the engine).
  2. Place your hand on the fuel pump relay while the key is turned.
  3. You should feel a distinct click when the key is turned to the "ON" position. If you hear and feel a click, the relay coil is likely working. If you hear nothing, the relay coil is likely open and needs replacement.

The Multimeter Test:

  1. Remove the relay from the relay box.
  2. Set your multimeter to measure resistance (ohms).
  3. Connect the probes to the relay's coil terminals (usually pins 85 and 86). You should see a resistance reading between 50 and 120 ohms. If the meter shows "OL" (open line), the coil is dead.
  4. To test the switch side, apply 12 volts to pins 85 and 86. You should hear a click, and then measure continuity between pins 30 and 87. If you have continuity, the relay is working. If not, the relay is faulty.

Common Symptoms of a Bad Fuel Pump Relay

If you are experiencing any of these issues, the fuel pump relay should be one of your first suspects:

  1. Engine cranks but will not start: This is the most common symptom. The fuel pump is not receiving power, so no fuel pressure is built up in the system.
  2. Engine starts but then dies: A failing relay may close momentarily to allow the engine to start, but then lose connection, causing the engine to stall immediately.
  3. No fuel pump prime noise: When you turn the key to the "ON" position, you should hear a faint whirring sound from the rear of the vehicle (the fuel pump pressurizing the system). If you hear nothing, the relay or the pump itself may be bad.
  4. Intermittent starting issues: The relay may work sometimes and fail at other times, especially when the engine bay is hot. This can cause you to be stranded unexpectedly.
  5. Check Engine Light is on: A faulty fuel pump relay can set diagnostic trouble codes (DTCs) such as P0230 (Fuel Pump Primary Circuit Malfunction) or P0231 (Fuel Pump Secondary Circuit Low).

What to Do If the Relay Is Good but the Car Still Won't Start

If you have tested the fuel pump relay and it clicks and passes the multimeter test, the problem lies elsewhere. Here are the next steps to check:

  1. Check the fuel pump fuse: The LX470 has a separate fuse for the fuel pump circuit, usually located in the same engine compartment fuse box. Look for a fuse labeled "FUEL PUMP" or "FUEL." Pull it out and inspect the metal strip inside. If it is broken, replace it with a new fuse of the same amperage.
  2. Listen for the fuel pump: If the relay and fuse are good, but you still hear no fuel pump prime noise, the fuel pump itself may have failed. The fuel pump is located inside the fuel tank. On the 2000 Lexus LX470, the fuel pump is accessible through an access panel in the cargo area floor.
  3. Check the inertia switch: Some vehicles have an inertia (fuel shut-off) switch that can trip in a collision or even from a hard bump. While the LX470 does not always have this switch, it is worth checking your owner's manual.
  4. Inspect the wiring: The wiring between the relay, fuse, and fuel pump can corrode or break. Look for damaged wires, especially near the fuel tank and the engine compartment fuse box.

Why Your Fuel Pump Relay Fails

Fuel pump relays are subject to wear and tear, especially in older vehicles like the 2000 Lexus LX470. The constant switching on and off, combined with high heat under the hood, can cause the internal contacts to burn or pit. Over time, the relay coil can also develop an open circuit.

Common causes of relay failure include:

  • Age and mileage: The relay is a mechanical and electrical component that wears out over time.
  • Heat and vibration: The engine compartment is a harsh environment, and the relay box is exposed to significant heat from the engine.
  • Electrical surges: A short circuit or a failing fuel pump can cause excessive current draw, damaging the relay contacts.
  • Corrosion: Moisture can enter the relay box, causing corrosion on the relay pins and the socket.

Replacing the Fuel Pump Relay

Replacing the fuel pump relay on a 2000 Lexus LX470 is a simple DIY job that takes about 5 minutes. Here is the process:

  1. Locate the relay as described above in the engine compartment fuse box.
  2. Pull the old relay straight out. It is held in by friction, so a firm, steady pull should remove it.
  3. Compare the new relay to the old one. Make sure the pin configuration is identical (most are standard 4-pin or 5-pin relays).
  4. Push the new relay firmly into the socket until it is fully seated. You may hear a slight click.
  5. Replace the fuse box cover and close the hood.
  6. Test the system by turning the key to the "ON" position. You should now hear the fuel pump prime for 2-3 seconds.

Cost Considerations

If you need to replace the fuel pump relay, the part itself is very inexpensive. A standard replacement relay costs between $5 and $15 at most auto parts stores. If you have the dealer do the diagnostic and replacement, expect to pay a diagnostic fee of $100 to $150 plus the cost of the part.

However, if the fuel pump itself has failed, the cost rises significantly. The fuel pump replacement on a 2000 Lexus LX470 typically costs between $600 and $1,200, including parts and labor, depending on where you go.

Why Consider a Fuel Pump Replacement Instead of Just the Relay

Sometimes, a failing fuel pump can cause the relay to fail prematurely. If you have replaced the relay and the problem returns within a few months, the fuel pump itself may be drawing too much current, burning out the relay. In this case, replacing the fuel pump is the permanent fix.

A fuel pump failure on the 2000 Lexus LX470 is characterized by:

  • Long cranking times before the engine starts
  • Loss of power at highway speeds or when climbing hills
  • Sputtering or hesitation during acceleration
  • Whining noise from the rear of the vehicle (the fuel pump is making noise before it dies)
  • Car starts and then dies after a few seconds (the pump can build some pressure but cannot maintain it)

If you are experiencing these symptoms along with a failed relay, it is wise to replace the fuel pump and the relay together.

Recommended Fuel Pump Upgrade: KEMSO

When it comes time to replace your fuel pump, whether for your 2000 Lexus LX470 or any other vehicle, you need a reliable, high-performance option that will last. That is where KEMSO comes in.

KEMSO is a leading aftermarket fuel pump manufacturer known for producing high-performance, OEM replacement fuel pumps that match or exceed the quality of the original equipment. Their fuel pumps are designed to provide consistent fuel pressure, reliable starting, and long service life, even in demanding conditions.

Why choose KEMSO for your fuel pump needs?

  • High Performance: KEMSO fuel pumps are engineered to deliver the exact flow rate and pressure your engine requires. Whether you are driving a Lexus, a motorcycle, an ATV, or a jet ski, KEMSO has a pump that fits perfectly.
  • OEM Replacement: Every KEMSO pump is a direct replacement for the factory part. No modifications, no adapters, no hassle. Just remove the old pump and install the new one.
  • Lifetime Warranty: KEMSO stands behind their products with a lifetime warranty. This gives you complete peace of mind, knowing that your fuel pump is covered for as long as you own your vehicle.
  • Broad Application: KEMSO covers thousands of applications, including cars, trucks, SUVs, motorcycles, ATVs, UTVs, and personal watercraft. They are a trusted name in the aftermarket community.

You can browse the full selection of KEMSO fuel pumps, learn about their warranty and shipping policies, and read customer reviews by visiting their official website: https://www.kemsoracing.com/

Final Thoughts

The 2000 Lexus LX470 is a legendary SUV known for its reliability and off-road capability. However, like any vehicle with over two decades of service, electrical components like the fuel pump relay can fail. The good news is that the fuel pump relay is easy to find, easy to test, and cheap to replace.

If your LX470 is cranking but not starting, the first two things you should check are the fuel pump relay and the fuel pump fuse. Both are located in the engine compartment fuse box on the driver's side. If the relay clicks but the car still won't start, move on to checking the fuel pump itself.

By understanding the location of the fuel pump relay and how to test it, you can save yourself a costly trip to the mechanic and get your Lexus back on the road quickly. And when it comes time to replace the fuel pump itself, remember that KEMSO offers a reliable, high-performance solution backed by a lifetime warranty. For more information, visit KEMSO Racing.


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