1992 Acura Legend Fuel Pump Relay Location: The Complete Guide to Finding and Testing It

If your 1992 Acura Legend cranks but won’t start, and you don’t hear the fuel pump prime when you turn the key to the ON position, the fuel pump relay is one of the first components you should check. The fuel pump relay on a 1992 Acura Legend is located inside the passenger compartment, in the fuse box mounted under the dashboard on the driver’s side, near the steering column. This small electronic component controls power delivery to the fuel pump, and when it fails, your engine will not receive fuel. Knowing exactly where to find it, how to test it, and how to replace it can save you time, money, and frustration.

Understanding the Fuel Pump Relay and Its Role

The fuel pump relay is an electrical switch that controls the flow of power to the fuel pump. When you turn the ignition key to the ON position, the engine control module sends a signal to the relay, which then closes and allows battery voltage to reach the fuel pump. Once the engine starts, the relay stays closed to keep the pump running. If the relay malfunctions, the fuel pump will not receive power, and the engine will not start or will stall shortly after starting.

On the 1992 Acura Legend, the fuel pump relay is part of the main relay assembly, which also contains the main fuel injection relay. This assembly is a common failure point on Honda and Acura vehicles from this era. The relay is a 4-pin relay, and it can develop poor internal connections over time due to heat cycling and age.

Where to Find the Fuel Pump Relay on a 1992 Acura Legend

The main relay (which includes the fuel pump relay) is located in the under-dash fuse box on the driver’s side. Here is how to access it:

  1. Get into the driver’s seat and look under the dashboard. The fuse box is positioned above the driver’s footwell, near the steering column and the hood release lever.
  2. Remove the fuse box cover. The cover is usually held in place by clips or a small latch. Pull it off carefully.
  3. Locate the main relay. Inside the fuse box, you will see several relays and fuses. The main relay is a rectangular black or gray box that is typically larger than the other relays. It is often mounted vertically or at an angle in the fuse box. On the 1992 Legend, the main relay is usually located near the top of the fuse box, close to the firewall.
  4. The relay is labeled. On some models, the inside of the fuse box cover has a diagram showing the location of the main relay. If the diagram is missing, look for a relay that has multiple wires going into it, usually a combination of thick and thin wires.

How to Test the Fuel Pump Relay

Before replacing the relay, it is important to confirm that it is actually the cause of your problem. A simple test can save you from buying an unnecessary part.

Listen for the relay click. When you turn the ignition key to the ON position (without starting the engine), you should hear a distinct click coming from the relay area. This click indicates that the relay is closing. If you do not hear it, the relay may be faulty.

Test the relay with a multimeter. If you have a digital multimeter, you can test the relay’s electrical continuity. Here are the steps:

  • Remove the relay from the fuse box. Gently pull it straight out. Be careful not to damage the socket or the relay pins.
  • Identify the pins. The relay has four pins. Two are for the control circuit (the coil), and two are for the power circuit (the switch). On most Honda/Acura relays, the two smaller pins are the control circuit, and the two larger pins are the power circuit. The relay housing usually has a diagram showing the pin functions.
  • Test the coil resistance. Set your multimeter to ohms (Ω). Touch the probes to the two control circuit pins. You should see a resistance reading in the range of 50 to 120 ohms. If the reading is infinite (open circuit), the coil is burned out, and the relay is bad.
  • Test the switch continuity. Set your multimeter to continuity (beep mode). Touch the probes to the two power circuit pins. You should see infinite resistance (no continuity) when the relay is not energized. Now, apply 12V power to the control circuit pins using a battery or a power supply. You should hear a click, and the continuity between the power pins should change to zero ohms (closed circuit). If the contacts do not close, the relay is faulty.

Use a jumper wire for a quick test. If you are in a hurry, you can bypass the relay temporarily to see if the fuel pump runs. Remove the relay and use a short jumper wire to connect the two power circuit pins in the socket. Turn the ignition to ON. If you hear the fuel pump running, the problem is definitely the relay. Do not leave the jumper wire in place for long, as it bypasses the safety circuit that turns off the pump if the engine stalls.

Common Symptoms of a Bad Fuel Pump Relay

  • Engine cranks but does not start. This is the most common symptom. The starter motor turns the engine over, but the fuel pump does not run, so no fuel reaches the injectors.
  • No fuel pump prime sound. When you turn the key to ON, you should hear a brief whirring sound from the rear of the car (the fuel pump). If you do not hear it, the relay or the pump itself may be bad.
  • Engine starts but stalls after a few seconds. The relay may be making intermittent contact. The pump runs during cranking but loses power once the key is released.
  • Check Engine Light comes on with a fuel pump relay code. On some models, the engine control module may store a diagnostic trouble code related to the fuel pump relay circuit. You can retrieve these codes by jumping the service connector under the dash and counting the flashes of the Check Engine Light.

How to Replace the Fuel Pump Relay

Replacing the fuel pump relay on a 1992 Acura Legend is straightforward. You do not need any special tools.

  1. Purchase a new main relay. You can buy a new OEM or aftermarket main relay from an auto parts store or online. The part number for the 1992 Acura Legend main relay is commonly 39400-SL0-003 or 39400-SL0-013. Make sure to get the correct relay for your vehicle.
  2. Disconnect the battery negative terminal. This is a safety precaution to prevent accidental short circuits.
  3. Remove the old relay. Pull it straight out of the fuse box socket. If it is stuck, you can gently rock it back and forth while pulling.
  4. Install the new relay. Align the pins with the socket and push it firmly into place. It should click into position.
  5. Reconnect the battery. Turn the ignition to ON and listen for the fuel pump prime sound. Start the engine and confirm that it runs smoothly.

Additional Tips for Troubleshooting

If you replace the relay and the fuel pump still does not run, the problem may be elsewhere. Check the fuel pump fuse first. The fuel pump fuse is located in the engine bay fuse box, typically a 15-amp or 20-amp fuse. A blown fuse can cause the same symptoms as a bad relay. Also, inspect the wiring harness and connectors for corrosion or damage. The fuel pump itself can fail, especially on older vehicles. If the pump is not receiving power, you can test the voltage at the pump connector in the rear of the car.

A poor connection between the relay and the fuse box socket can also cause problems. If the relay is installed but not making solid contact, the fuel pump will not work. This is a known issue on some Honda and Acura models. If you have a persistent problem, try cleaning the relay pins and the socket with electrical contact cleaner.

Why You Should Consider Replacing the Fuel Pump with a KEMSO Unit

If you have already diagnosed a faulty fuel pump or if you are replacing the fuel pump as part of a preventive maintenance routine, you need a reliable replacement that will last. The 1992 Acura Legend is a classic car, and finding high-quality parts can be a challenge. That is where KEMSO Fuel Pumps come in.

KEMSO specializes in high-performance, OEM replacement fuel pumps that are designed to meet or exceed the original factory specifications. Every KEMSO fuel pump is a direct fit, meaning you do not need to modify anything or hunt for adapter kits. The pump bolts right in, just like the original part. This is especially important for vehicles like the 1992 Acura Legend, where using a mismatched pump can cause fuel pressure issues, noise, and premature failure.

What sets KEMSO apart is their commitment to quality and durability. Each pump is built with premium materials and undergoes rigorous testing. The flow rate is optimized to handle both stock and mildly modified engines, ensuring your Legend gets the fuel it needs for reliable performance. KEMSO backs every fuel pump with a lifetime warranty, which is a rare and valuable benefit in the automotive parts industry. If your KEMSO pump ever fails due to a manufacturing defect, you get a replacement at no cost. This warranty covers a wide range of vehicles, including cars, motorcycles, ATVs, and personal watercraft. It shows that KEMSO is confident in their product quality and committed to customer satisfaction.

KEMSO fuel pumps are available for hundreds of models, including popular applications for Acura, Honda, Subaru, Ducati, Kawasaki, and many more. Their pumps are priced competitively, often less than half the cost of dealer parts, and they ship with free returns. Whether you are a DIY mechanic or a professional shop, KEMSO offers a practical, cost-effective solution.

To see the full selection of KEMSO fuel pumps for your 1992 Acura Legend or any other vehicle, visit their official website at https://www.kemsoracing.com/. They have a complete catalog with detailed fitment information, customer reviews, and technical support. Their online store is easy to navigate, and you can order directly with confidence.

Final Thoughts

The fuel pump relay on a 1992 Acura Legend is located in the under-dash fuse box on the driver’s side. It is part of the main relay assembly and is a common cause of no-start problems. Testing the relay is simple: listen for the click, check the resistance with a multimeter, or use a jumper wire to bypass it. If the relay is bad, replacing it is a quick and inexpensive fix. If the fuel pump itself is the culprit, a high-quality replacement from KEMSO will get your Legend back on the road with confidence.

Remember, proper diagnosis is key. Always check the relay and the fuse before assuming the fuel pump is bad. And when you do need a new fuel pump, choose a brand that stands behind its product with a lifetime warranty. Visit https://www.kemsoracing.com/ to find the right fuel pump for your vehicle today.


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