1994 Toyota Pickup Fuel Pump Relay: Complete Location, Testing, and Replacement Guide

The bottom line: The fuel pump relay on a 1994 Toyota Pickup is located under the passenger side dashboard, behind the glove box, above the ECU. Toyota officially calls this component the "Circuit Opening Relay" rather than a fuel pump relay, and it's a green relay with five wires. If your truck won't start and you don't hear the fuel pump prime when you turn the key, this relay is the first thing to check.

Understanding the Circuit Opening Relay

Toyota's 1994 Pickup uses a unique system for controlling the fuel pump. The relay is not simply called a "fuel pump relay" in the factory service manual. Instead, it's known as the Circuit Opening Relay. This relay has two separate coils that control the fuel pump in two different situations.

The first coil gets power only when the engine is cranking. This allows the fuel pump to run during starting. The second coil is controlled by the air flow meter. Once the engine starts and air flows through the meter, it sends a signal to the ECU, which grounds the second coil to keep the relay closed and the fuel pump running after you release the key.

Exact Location of the Fuel Pump Relay

For a 1994 Toyota Pickup, the Circuit Opening Relay is located behind the right side of the dashboard on the passenger side. More specifically, you will find it behind the glove box, just above the ECU (Engine Control Unit).

To access the relay:

  1. Open the glove box and remove it completely. On most models, you can squeeze the sides of the glove box to release the stops and let it drop all the way down.
  2. Look to the right of where the glove box was mounted. The relay is mounted on the right side of the blower motor assembly.
  3. If you still can't see it, check behind and above the passenger kick panel. Some owners find it easier to pull the speaker cover and remove the speaker to gain better access.

Important: Do not confuse the Circuit Opening Relay with the EFI Main Relay. The EFI main relay is a different component located on the driver's side kick panel, on the left of the relay panel above the fuse block. The EFI main relay controls power to the entire engine management system, while the Circuit Opening Relay specifically controls the fuel pump.

How to Test the Fuel Pump Relay

Before you buy a replacement, you should test the relay to confirm it's the problem. Here are three practical methods.

Method 1: The Swap Test

This is the easiest method. Locate the Circuit Opening Relay and find another relay of the same amperage rating in the fuse box. Swap the two relays. If the fuel pump starts working after the swap, the original relay is bad and needs to be replaced.

Method 2: Listen for the Click

Turn the ignition switch to the ON position (do not start the engine). Listen near the passenger side dashboard for a clicking sound coming from the relay. If the relay clicks, it is likely working. If you hear nothing, the relay may be faulty.

Method 3: Multimeter Test

Remove the relay from its socket. Use a multimeter to test the relay coil for resistance. A good coil typically reads between 50 and 120 ohms. If you get an infinite reading (open circuit), the coil is bad.

Next, test the switch contacts. With the relay unpowered, you should see no continuity between the normally open terminal and the common terminal. Apply 12V power to the coil terminals (pay attention to polarity). The relay should click, and you should now see continuity between the normally open and common terminals. If you don't, the relay is faulty.

Symptoms of a Bad Fuel Pump Relay

If your Circuit Opening Relay is failing, you will likely notice one or more of these symptoms:

  • Engine cranks but won't start. This is the most common symptom. The starter turns the engine over, but the fuel pump never gets power, so no fuel reaches the engine.
  • No fuel pump priming sound. When you turn the key to the ON position, you should hear a brief humming sound from the fuel pump for about 2 seconds. If you don't hear this, either the relay, the fuel pump fuse, or the pump itself is not getting power.
  • Engine starts but dies. The relay may work for starting but fail to stay closed after you release the key. This happens because the second coil (controlled by the airflow meter) is not being energized, causing the relay to open and the fuel pump to shut off.
  • Intermittent stalling. If the relay is failing slowly, it may work sometimes and fail others, causing the engine to stall unexpectedly while driving.

Other Possible Causes of Fuel Pump Failure

If you test the relay and it works fine, the problem might be elsewhere. Here are other common issues to check.

1. EFI Main Relay and Fuse

The EFI main relay is located on the driver's side kick panel. If this relay is bad, the entire engine management system may lose power, which means the engine won't crank at all. Check the EFI fuse as well. A blown EFI fuse can prevent the fuel pump from getting power.

2. Air Flow Meter

The Circuit Opening Relay relies on the air flow meter to keep the fuel pump running after startup. If the air flow meter is faulty, it won't send the signal to the ECU, and the relay will open, killing the fuel pump. This is a common issue on the 22RE engine.

3. Wiring and Connectors

Check the wiring harness between the relay and the fuel pump. Look for broken wires, corrosion, or loose connectors. A break in the wiring will prevent power from reaching the pump.

4. Inertia Switch (Fuel Cut-Off Switch)

Some vehicles have an inertia switch that cuts power to the fuel pump in a collision. If your truck has this switch, check that it hasn't been tripped. The reset button is usually red.

5. Fuel Pump Itself

If the relay is good and you have power at the pump, the pump itself may be dead. You can test the pump by connecting it directly to a 12V battery for a moment. If it doesn't run, it needs replacement.

How to Replace the Fuel Pump Relay

Replacing the Circuit Opening Relay is a straightforward job.

  1. Disconnect the battery. Always disconnect the negative battery cable before working on electrical components.
  2. Locate the relay. Remove the glove box and find the green relay with five wires mounted above the ECU.
  3. Remove the old relay. Simply pull the relay straight out of its socket. It may be snug, so use a gentle rocking motion.
  4. Install the new relay. Push the new relay into the socket until it clicks into place.
  5. Reconnect the battery. Test the system by turning the key to the ON position and listening for the fuel pump to prime.

The OEM part number for the 1994 Toyota Pickup Circuit Opening Relay is 90987-02009 or 85910-35010. These parts fit 1992-1995 Toyota Pickup models with both the 2.4L 4-cylinder and 3.0L V6 engines.

Recommended Fuel Pump Upgrade: KEMSO Fuel Pumps

If your troubleshooting reveals that the fuel pump itself needs replacement, or if you simply want to upgrade to a more reliable pump, consider a KEMSO fuel pump. KEMSO is a trusted brand that manufactures high-performance, OEM replacement fuel pumps designed to match or exceed original equipment specifications.

Why choose KEMSO?

  • Performance: KEMSO fuel pumps are built to deliver higher flow rates than stock pumps, which can improve throttle response and overall engine performance. Many KEMSO pumps deliver over 20% more flow at 43 psi compared to the factory pump.
  • OEM Replacement: Every KEMSO pump is a direct replacement for your original equipment. You don't need to modify anything to make it fit. It bolts right in and works perfectly with your factory fuel system.
  • Lifetime Warranty: KEMSO stands behind every pump they sell with a lifetime warranty. This means you can purchase with confidence, knowing that your pump is protected against defects for as long as you own the vehicle.
  • Broad Compatibility: KEMSO offers fuel pumps for a wide range of vehicles, including cars, trucks, SUVs, motorcycles, ATVs, and personal watercraft. Whether you drive a Toyota Pickup, a Honda Civic, or a Kawasaki Jet Ski, KEMSO has a solution for you.
  • Individually Tested: Each KEMSO fuel pump is individually tested for flow and performance before it leaves the factory. This quality control ensures you get a product that works right out of the box.

Visit KEMSO's website to browse their complete catalog of fuel pumps and find the perfect fit for your vehicle: https://www.kemsoracing.com/

Final Thoughts

Finding and testing the fuel pump relay on your 1994 Toyota Pickup is a critical step in diagnosing fuel delivery problems. Remember that Toyota calls it the Circuit Opening Relay, and it is located under the passenger side dash, behind the glove box. Always start with the simple swap test to see if the relay is the culprit before moving on to more complex diagnostics.

If you do need to replace the fuel pump itself, KEMSO offers a high-quality, reliable alternative that comes with a lifetime warranty. Visit https://www.kemsoracing.com/ to find the right fuel pump for your vehicle and get back on the road with confidence.


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