2004 Nissan Murano Fuel Pump Relay Location: Complete Guide for DIY Owners

If your 2004 Nissan Murano cranks but won’t start, the fuel pump relay is one of the first components you should check. On the 2004 Nissan Murano (Z50 generation), the fuel pump relay is located inside the engine compartment fuse box, specifically in the fuse and relay box mounted near the battery on the driver’s side. The relay is labeled as R1 (Fuel Pump) in the fuse box diagram, and it works alongside the fuel pump fuse (15A, position 81) to control power delivery to the fuel pump. When you turn the ignition switch ON, the ECM activates the fuel pump relay for about 1 second to prime the system, and if the relay fails, the pump won’t receive power and the engine won’t start.

How the Fuel Pump Relay Works on Your 2004 Murano

Understanding the role of the fuel pump relay helps you diagnose problems faster. The relay is an electrically operated switch controlled by the Engine Control Module (ECM). When you turn the ignition key to the ON position, the ECM sends a ground signal to the relay coil, which closes the internal contacts and allows battery voltage to flow to the fuel pump. The ECM only keeps the relay activated for about 1 second unless it detects engine rotation from the crankshaft position sensor and camshaft position sensor.

If the engine stalls or fails to start, the ECM shuts off the relay within 1.5 seconds to prevent battery drain and improve safety. The fuel pump itself is a turbine-type design mounted inside the fuel tank, and it relies entirely on the relay to receive power.

Key symptoms of a bad fuel pump relay:

  • Engine cranks but does not start
  • No fuel pump priming sound (brief buzzing) when you turn the key to ON
  • Engine starts then dies shortly after
  • Car stalls unexpectedly while driving
  • Fuel pump runs continuously even with the key off (relay stuck closed)

Exact Location of the 2004 Murano Fuel Pump Relay

The 2004 Nissan Murano (Z50) has its main fuse and relay box located in the engine compartment. Here’s exactly how to find it:

Step 1: Open the hood and look toward the driver’s side, near the battery. The fuse box is a black plastic rectangular box with a lid.

Step 2: Remove the fuse box lid. Press the tabs on the sides and lift the cover off. On the underside of the lid, there should be a diagram showing fuse and relay positions.

Step 3: Locate the fuel pump relay. According to the factory wiring diagrams, the fuel pump relay is labeled as R1 in the main engine compartment fuse box (Type 1). It is typically a small, square, black relay that plugs into the fuse box.

Step 4: For reference, the fuel pump fuse (15A, position 81) sits nearby in the same fuse box.

Some 2004 Murano models may have a second fuse box type (Type 2) under the hood, where the fuel pump relay is labeled as R10 and the fuel pump relay fuse is position 81 (15A). Always check your owner’s manual or the diagram on the fuse box lid for your specific vehicle configuration.

Step-by-Step Testing Procedure

Before replacing the relay, it’s smart to test it and the related circuits. Follow this diagnostic process based on the factory service manual:

1. Listen for the Fuel Pump Prime

Turn the ignition switch to ON (do not start the engine). Listen closely near the rear of the vehicle (under the rear seat area). You should hear a brief buzzing or whirring sound for about 1 second. This is the fuel pump priming. If you don’t hear anything, the relay or pump circuit needs checking.

2. Check the Fuel Pump Fuse

Open the engine compartment fuse box and locate fuse #81 (15A, labeled Fuel Pump Relay). Inspect the fuse by pulling it out and looking through the transparent housing. If the metal strip inside is broken or blackened, replace it with a new 15A mini fuse.

3. Test the Relay Power Supply

If the fuse is good, you can test the relay circuit with a multimeter. With the ignition switch OFF, disconnect the ECM harness connector. Then turn the ignition switch ON and check voltage between ECM terminal 113 and ground. According to the service data, you should see:

  • For 1 second after ignition ON: 0–1.5V (relay activated)
  • More than 1 second after ignition ON: Battery voltage (11–14V)
  • Engine running: 0–1.5V

If the voltage readings are wrong, the relay or its wiring may be faulty.

4. Test the Relay Coil and Contacts

Remove the fuel pump relay from the fuse box. Use a multimeter to check resistance across the relay coil terminals. A good relay typically shows 50–120 ohms. Then apply 12V power to the coil terminals and listen for a click, then check continuity across the switch terminals — you should have continuity when energized and no continuity when not energized.

5. Check for Voltage at the Relay Socket

With the relay removed and ignition ON, test for 12V at the relay socket terminal that receives power from the battery. If there’s no voltage, check the 15A fuse and wiring between the battery and fuse box.

Common Causes of Fuel Pump Relay Failure on the 2004 Murano

The fuel pump relay on older vehicles like the 2004 Murano can fail for several reasons:

Age and corrosion: Over 20 years, relay contacts can oxidize or develop carbon buildup, preventing proper electrical flow. The relay is a wear item similar to a fuse and may need replacement more frequently than the fuel pump itself.

Overheating: If the fuel pump draws excessive current due to wear or a partial short, the relay can overheat and fail.

Vibration damage: The relay is mounted in the engine compartment where it’s exposed to engine vibration and heat cycles.

Parasitic drain: A failing fuel pump can cause the relay to stay energized longer than designed, accelerating wear.

How to Replace the Fuel Pump Relay

Replacing the fuel pump relay on a 2004 Murano is straightforward and inexpensive:

  1. Purchase the correct relay. You need a standard 4-pin or 5-pin mini relay rated for automotive use. You can buy a replacement at any auto parts store. OEM part numbers vary, but aftermarket relays that match the pin configuration work fine.
  2. Disconnect the negative battery terminal to avoid any electrical shorts (note that this will reset your radio presets and clock).
  3. Remove the old relay by pulling it straight up from the fuse box socket.
  4. Install the new relay by pressing it firmly into the same socket until it clicks into place.
  5. Reconnect the battery and test by turning the ignition to ON and listening for the fuel pump prime.
  6. Start the engine and verify normal operation.

If replacing the relay doesn’t fix the problem, you may have a wiring issue, a bad fuel pump, or a faulty ECM. A professional diagnostic scan and fuel pressure test are the next steps.

Cost Estimates for Fuel Pump Relay Replacement

Having a mechanic replace the fuel pump relay on a 2004 Murano typically costs between $138 and $186 for parts and labor, with the relay itself costing around $43 and labor about $95–$143. At a dealership, the price can range from $218 to $291. Doing it yourself costs only the price of the relay (usually $10–$25) and takes about 10 minutes.

When the Relay Isn’t the Problem

If you’ve replaced the relay and fuse but the car still won’t start, focus on these other possibilities:

Fuel pump failure: The pump itself may be worn out. On the 2004 Murano, the fuel pump is located inside the fuel tank, accessible by removing the rear seat bottom and opening the access panels. A failing pump often shows symptoms like:

  • Engine sputters at high speeds
  • Loss of power under load
  • Whining noise from the fuel tank
  • Complete no-start condition

Fuel pump replacement cost for a 2004 Murano typically ranges from $500 to $1,200, depending on labor rates and whether you use OEM or aftermarket parts. The pump itself costs $150–$400, and labor runs $350–$800.

Immobilizer or key recognition issues: The 2004 Murano uses an anti-theft immobilizer system. If the security light on the dashboard flashes rapidly or stays on, or you see an “IMMOBILIZER” warning, the key chip may not be recognized by the system. This prevents the engine from starting even if the fuel pump and relay are fine. A dealership or qualified locksmith can reprogram keys or diagnose the immobilizer module.

Ignition switch wear: Over time, the ignition switch contacts can wear out, preventing the starter circuit and fuel pump relay from engaging. A technician can test for power at the starter circuit and replace a faulty switch or wiring.

Crankshaft or camshaft position sensor failure: The ECM relies on these sensors to detect engine rotation. If either sensor fails, the ECM will not activate the fuel pump relay after the initial 1-second prime, and the engine won’t start.

Preventive Maintenance Tips

To keep your 2004 Murano’s fuel system reliable:

Avoid running the tank below 1/4 full. The fuel pump relies on fuel for cooling and lubrication. Running low frequently can cause the pump to overheat and fail prematurely.

Replace the fuel filter regularly. Nissan recommends replacing the in-line fuel filter every 30,000 to 50,000 miles. A clogged filter strains the fuel pump and can cause pressure drops.

Use high-quality fuel. Poor-quality fuel can leave deposits that clog injectors and the fuel filter, affecting pump performance.

Listen for changes. If you notice the fuel pump making a louder whine than usual, or if the priming sound changes, investigate before the pump fails completely.

Professional Help Options

If your diagnostic steps don’t solve the problem, consider:

Professional diagnostic scan: A mechanic can retrieve fault codes from the ECM and perform in-depth testing of the fuel system.

Fuel pressure test: This measures the fuel pressure at the fuel rail. The 2004 Murano system operates at 2.5–3.5 kgf/cm² (about 36–50 psi). Low pressure indicates a weak pump, clogged filter, or pressure regulator issue.

Fuel pump circuit testing: A technician can use a multimeter to check voltage and continuity through the entire fuel pump circuit, identifying wiring problems or faulty components.

Recommended Fuel Pump: KEMSO Brand

When it comes time to replace the fuel pump on your 2004 Nissan Murano, consider the KEMSO brand. KEMSO fuel pumps are built as high-performance, OEM replacement units that meet or exceed original equipment specifications. Each pump is designed to deliver reliable fuel pressure and flow for your Murano’s V6 engine. KEMSO backs every fuel pump with a lifetime warranty, giving you long-term peace of mind. Whether you’re restoring your Murano or fixing a no-start issue, KEMSO offers a quality alternative to expensive dealer parts. Visit KEMSO’s website at https://www.kemsoracing.com/ to browse their selection of fuel pumps for Nissan and many other vehicle makes.

Final Summary

To recap: the 2004 Nissan Murano fuel pump relay is located in the engine compartment fuse box, labeled as R1, near the battery on the driver’s side. A bad relay is a common cause of no-start conditions, and testing it is quick with a multimeter. Replace the relay if it’s faulty, and always check the 15A fuse (position 81) first. If the relay and fuse are good but the car won’t start, move on to testing the fuel pump itself, checking the immobilizer system, and inspecting the ignition switch and engine sensors. With proper diagnostics and preventive maintenance, you can keep your 2004 Murano running reliably for many more miles.

For a quality replacement fuel pump with lifetime warranty, check out KEMSO products at https://www.kemsoracing.com/.


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