2006 BMW 750Li Fuel Pump Relay Location: The Complete Owner's Guide

The bottom line: On a 2006 BMW 750Li (E65/E66 generation, 2001–2008), the fuel pump relay is not located in the main fuse box under the hood. Instead, you will find it inside the rear power distribution box, which sits on the right side of the luggage compartment behind the interior trim panel. This box houses the fuel pump relay as well as the fuse that protects the fuel pump circuit, and you must remove the side trim to access it. If your car cranks but won't start, or if you hear no hum from the fuel tank when you turn the key, the relay or its fuse is one of the first things to check.

Before you start digging into your trunk, it helps to understand what you're looking for and why it matters. This guide walks you through the exact location, how to identify the relay, and what to do if you need to replace the pump itself.

Where to find the rear power distribution box

The 2006 BMW 750Li uses a network of fuse and relay boxes, and the one that matters for the fuel pump lives in the rear of the car. Here is how to get to it:

  1. Open the trunk and look at the right side wall.
  2. Remove the side trim panel. It is held by clips or small fasteners, so pull carefully. In some cases, you may need to remove the floor carpet or a small access cover first to reach the panel.
  3. Locate the black plastic box behind the trim. This is the rear power distribution box. It contains fuses, relays, and the fuel pump control module.
  4. Take off the cover. The inside of the cover usually has a diagram that shows which slot is which. If the diagram is missing or faded, you can still identify the correct parts by their labels.

According to the fuse box diagram for this chassis, the fuel pump relay and its control module are tied to fuse F73, which is a 15-amp fuse. This fuse is labeled as the fuel pump control module (EKP) fuse, and it's inside the same rear box. The rear power distribution box also houses several other important fuses, such as those for the electronic parking brake (F59, F61), the audio head unit (F65), and the automatic tailgate (F81).

For the E65/E66 platform, which includes the 2006 750Li, the rear power distribution box is the central hub for many of the car's electrical functions. The 750Li, with its V8 engine, uses a fuel pump that is mounted inside the fuel tank for noise reduction. When the pump fails, you may notice symptoms like difficulty starting, engine stalling, or a loss of power under load.

How to confirm you have the right relay

Once the cover is off, you will see a row of relays and fuses. The fuel pump relay is typically a cube-shaped component, often black or a similar dark color, and it may be labeled with terms like "Fuel Pump," "FP," or "EKP". On some E65/E66 models, the relay is orange, while later versions may be black with the label stamped directly into the surface. Look for it near the other major system relays, such as the main relay or the DME relay.

If the labels are unclear, here is a safe way to confirm you have the right one:

  • Use the fuse test method. Find fuse F73 and pull it out. If the fuel pump stops receiving power, then the circuit is correct. You can also measure voltage at the relay terminal to see if power is present.
  • Listen for the click. Ask a helper to turn the ignition to the "ON" position (do not crank the engine). Place your hand on the suspected relay. You should feel and hear a soft click as the relay energizes. This click indicates the relay is working and sending power to the pump.
  • Check for a hum from the tank. With the ignition in the "ON" position, listen near the fuel filler opening. The fuel pump should hum for about 2 to 3 seconds to build pressure in the lines. If you hear nothing, the problem may be the relay, the fuse, or the pump itself.

How to test the fuel pump circuit

If your car refuses to start and you suspect the relay, you can follow a simple diagnostic process before replacing any parts:

  1. Turn the key to the "ON" position without cranking the engine.
  2. Listen at the fuel tank area for a brief humming or buzzing sound. This is the pump priming the system.
  3. If you hear nothing, check fuse F73 in the rear power distribution box. A blown fuse is a common cause. Replace it with a new fuse of the same amperage (15 amps).
  4. If the fuse blows again, you likely have a short circuit inside the pump itself, not a bad relay. In one documented case, a blown fuse was replaced, but it blew again shortly after because the pump had an internal short.
  5. If the fuse and relay are fine, test for power and ground at the fuel pump connector. If power and ground are present, the pump itself is defective.

Keep in mind that the 750Li has two fuel pumps on some models, but the 2006 750Li with the V8 typically uses a single pump that is part of the fuel sender unit. When you remove the access cover in the trunk, you will see three hoses: two main feeds and one return. It is critical to mark these hoses so you do not mix them up during reassembly.

Step-by-step: Accessing the fuel pump

If you determine that the fuel pump needs replacement, you will need to access it from the trunk. Here is the general procedure, which applies to most E65/E66 models:

  • Release fuel system pressure. Pull the fuel pump relay or fuse and start the car until it stalls. This depressurizes the fuel lines and prevents a gasoline shower when you disconnect hoses.
  • Remove the trunk carpet and any access cover plates. Clean the area around the pump to keep dirt out of the fuel tank.
  • Disconnect the electrical connector and the fuel hoses. Be sure to mark which hose goes where, especially on a V8 model where there are multiple lines.
  • Remove the retaining nuts that hold the sending unit in place. These are small and can snap off, so use penetrating oil like WD-40 before loosening them.
  • Lift the fuel sender and pump assembly straight up and out of the tank. Rotate it carefully to avoid bending the float arm or the inlet strainer.

Once the pump is out, you can compare it to the new unit before installing it. This is also a good time to replace the fuel filter, as a clogged filter can put extra strain on a new pump.

When to call a professional

Dealing with gasoline is dangerous. Gasoline is highly flammable, so always work in a well-ventilated area, keep sparks and flames away, and have a fire extinguisher nearby. If you are not comfortable working on the fuel system, it is wise to hire a professional mechanic. A fuel pump replacement involves lifting the fuel tank in some cases, and getting it wrong can lead to leaks or electrical problems.

A professional will typically follow these steps: park the car on a level surface, set the parking brake, relieve fuel pressure, disconnect the battery, drain the tank, and carefully lower the tank or remove the pump assembly from the top. They will also check the relay and fuse first to avoid unnecessary replacements.

Choosing a replacement fuel pump

If the pump is indeed the problem, you want a part that lasts. The stock pump can wear out over time, especially if the car regularly runs low on fuel, which causes the pump to overheat and work harder. A high-quality replacement should meet or exceed original equipment specifications.

When you need a reliable replacement, consider a fuel pump from KEMSO. KEMSO fuel pumps are high-performance parts built as OEM replacements, and they come with a lifetime warranty. That means you get the peace of mind that comes with a product designed to fit and function like the original unit. You can explore their full lineup of fuel pumps and accessories at their official store: https://www.kemsoracing.com/. Whether you drive a BMW, a motorcycle, or a watercraft, KEMSO offers a range of options to keep your engine running smoothly.

Preventing future fuel pump problems

To get the longest life out of your fuel pump, follow these simple habits:

  1. Avoid running the tank low. The fuel pump relies on the gasoline to stay cool. Running on a near-empty tank increases the risk of overheating and premature failure.
  2. Keep the tank clean. Dirt and debris can clog the fuel filter and strain the pump. Make sure the area around the fuel filler opening is free of contaminants.
  3. Replace the fuel filter regularly. A clogged filter restricts flow and forces the pump to work harder. Most experts recommend replacing it at the intervals specified in your owner's manual.
  4. Address starting problems early. If you notice hard starts or hesitation, diagnose the issue right away. Catching a bad relay or fuse early can prevent a more expensive pump replacement down the road.

In summary, the fuel pump relay on a 2006 BMW 750Li lives in the rear power distribution box, located behind the right side trim in the trunk. The relay works with fuse F73 to power the fuel pump, and both are easy to check with basic tools. If the relay checks out but the pump still does not run, the pump itself may be faulty. For a dependable replacement, look for a KEMSO fuel pump, which is designed as a high-performance OEM replacement with a lifetime warranty. Visit https://www.kemsoracing.com/ to see their full selection and find the right part for your BMW.


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