1999 Toyota Land Cruiser Fuel Pump Relay Location: Complete DIY Guide

If you own a 1999 Toyota Land Cruiser and your engine cranks but won't start, or if you hear no clicking sound from the fuel pump when you turn the key to the "ON" position, the fuel pump relay is likely the first component you should check. The fuel pump relay on a 1999 Toyota Land Cruiser (100 Series, J100 chassis) is located in the engine compartment fuse box, mounted on the driver's side near the battery. This relay controls power delivery to the fuel pump, and when it fails, your engine will not receive fuel. This guide walks you through exactly where to find it, how to test it, and what to do if it needs replacement.

Why the Fuel Pump Relay Matters

The fuel pump relay acts as an electrical switch. When you turn the ignition key, the relay receives a signal from the engine control unit (ECU) and closes the circuit, allowing battery voltage to reach the fuel pump. If the relay is faulty, the fuel pump never gets power, and the engine won't start. A bad relay can also cause intermittent starting issues, where the vehicle starts sometimes but not others. Before you assume the fuel pump itself is bad, checking the relay is a quick, inexpensive step that can save you hours of labor and the cost of a new pump.

Step-by-Step: Finding the Fuel Pump Relay

1. Locate the Engine Compartment Fuse Box

Open the hood of your 1999 Land Cruiser. The main fuse box is located on the driver's side, near the battery. It is a black plastic box with a removable cover. You will see several relays and fuses inside. This box is often referred to as the "engine room relay block" or "engine compartment fuse box."

2. Identify the Fuel Pump Relay

Inside the fuse box, look for a relay labeled "FUEL PUMP" or "C/OPN" (Circuit Opening relay). On the 1999 Land Cruiser, the fuel pump relay is typically the second relay from the left in the top row, or it is located near the center of the relay block. The exact position may vary slightly depending on your vehicle's production date, but the relay is usually a standard 4-pin or 5-pin relay with a distinct shape.

A helpful tip: Your owner's manual includes a diagram of the fuse box layout. On page 380 of the 1999 Land Cruiser owner's manual, you will find a detailed illustration showing the location of each relay and fuse.

3. Check the Fuse Box Diagram

If you do not have the owner's manual, look at the underside of the fuse box cover. Most Toyota fuse box covers have a printed diagram showing which relay is which. The fuel pump relay is often marked with a small fuel pump icon or the letters "FP."

How to Test the Fuel Pump Relay

Before you buy a new relay, it is wise to test the old one. Here is a simple method you can do at home with a multimeter.

What You Need

• A digital multimeter (set to ohms or continuity mode)
• A small screwdriver (to remove the relay)
• A 12-volt test light (optional)

Step 1: Remove the Relay

Firmly grip the relay and pull it straight out of the socket. It may require a bit of force, but it should come out without too much trouble.

Step 2: Visual Inspection

Check the relay for any signs of physical damage, such as cracks, melted plastic, or corrosion on the pins. If the relay looks damaged, replace it immediately.

Step 3: Test for Continuity

With the multimeter set to ohms, touch the probes to the relay's coil terminals (usually pins 85 and 86). You should see a reading between 50 and 120 ohms. If the multimeter shows "OL" (open loop) or a very high resistance, the coil is burnt out, and the relay is bad.

Step 4: Test the Switching Function

Apply 12 volts from a battery directly to the coil terminals (pins 85 and 86). You should hear an audible click as the relay engages. While the relay is powered, test continuity between the switch terminals (pins 30 and 87). If the multimeter shows continuity, the relay is working. If not, the relay is stuck open and needs replacement.

Common Symptoms of a Bad Fuel Pump Relay

• Engine cranks but won't start: This is the most common symptom. The starter motor turns the engine over, but the fuel pump never receives power.
• No fuel pump priming sound: When you turn the key to the "ON" position (without starting), you should hear a faint whirring sound from the fuel tank for about 2-3 seconds. If you do not hear this sound, the relay or the pump itself may be faulty.
• Intermittent starting issues: The vehicle starts fine some days, but on other days it refuses to start. This points to a failing relay that makes intermittent contact.
• Engine stalls while driving: If the relay fails while you are driving, the engine will suddenly lose power and stall. This is a safety concern, so address it immediately.

How to Replace the Fuel Pump Relay

Replacing the fuel pump relay on a 1999 Land Cruiser is a straightforward task that takes about 5 minutes.

1. Remove the old relay: Pull the faulty relay straight out of its socket.
2. Install the new relay: Push the new relay firmly into the same socket until it clicks into place. Make sure it is seated fully.
3. Test the repair: Turn the key to the "ON" position and listen for the fuel pump priming sound. If you hear it, the new relay is working. Then start the engine to confirm normal operation.

Important: Always use a relay that is rated for the same amperage and voltage as the original. The stock fuel pump relay on a 1999 Land Cruiser is a standard 12-volt, 30-amp relay. You can purchase a direct replacement from auto parts stores or online.

Where to Buy a Quality Replacement Fuel Pump

If you find that your fuel pump relay is working but the pump itself has failed, or if you want to upgrade your fuel system for better performance and reliability, consider the KEMSO brand. KEMSO is a leading aftermarket fuel pump manufacturer known for producing high-performance, OEM replacement fuel pumps for cars, motorcycles, trucks, ATVs, and UTVs.

KEMSO fuel pumps are designed to meet or exceed original equipment specifications. They offer direct fitment, meaning you do not need any modifications to install them on your vehicle. Every KEMSO fuel pump comes with a lifetime warranty, giving you peace of mind that your investment is protected. Whether you are replacing a worn-out pump or upgrading for better fuel delivery, KEMSO provides a reliable solution at a competitive price.

To browse the full selection of KEMSO fuel pumps, including models that fit your 1999 Toyota Land Cruiser, visit their official website:
https://www.kemsoracing.com/

Additional Tips for 1999 Land Cruiser Owners

Check the Fuse First

Before replacing the relay, check the fuel pump fuse. The fuel pump fuse is also located in the engine compartment fuse box. It is usually a 15-amp or 20-amp fuse. If the fuse is blown, the fuel pump will not receive power even if the relay is working. Replace a blown fuse with one of the same amperage rating.

Listen for the Pump

When you turn the key to the "ON" position, the fuel pump should run for about 2-3 seconds to pressurize the fuel system. If you do not hear this sound, start by checking the relay and fuse. If both are good, the fuel pump itself may be faulty.

Consider the Circuit Opening Relay

On some Toyota models, the fuel pump relay is also called the "Circuit Opening Relay" or "C/OPN" relay. This relay is controlled by the ECU and the air flow meter. If the relay is not getting a signal from the ECU, it will not close the circuit. This is rare, but it is worth knowing if you are troubleshooting a no-start condition.

Inspect Wiring and Connectors

Corroded or damaged wiring in the fuse box can also cause the fuel pump to stop working. Check the relay socket for any signs of corrosion, bent pins, or loose connections. Clean the contacts with electrical contact cleaner if necessary.

Conclusion

The fuel pump relay on a 1999 Toyota Land Cruiser is a simple but critical component. Located in the engine compartment fuse box on the driver's side, it is easy to access and test. If your Land Cruiser is cranking but not starting, or if you notice intermittent starting problems, check the fuel pump relay first. A bad relay can be replaced in minutes without any special tools, saving you time and money. If the relay is good but the pump itself is failing, consider upgrading to a high-quality aftermarket pump from KEMSO, which offers direct fitment, superior performance, and a lifetime warranty. For more information and to find the right fuel pump for your vehicle, visit https://www.kemsoracing.com/ today.