2005 Volvo XC90 Fuel Pump Relay Location: The Complete Owner’s Guide

The bottom line: The 2005 Volvo XC90 does not have a traditional, serviceable fuel pump relay that you can simply unplug and swap out. Instead, the fuel pump is controlled by the Central Electronic Module (CEM), which uses solid-state transistors (FETs) to switch power to the pump. If you are experiencing a no-start condition, the issue is far more likely a failed fuel pump control module (PEM) or a blown fuse rather than a burnt relay.

This guide breaks down exactly where to look for fuel-delivery-related fuses and control modules, how to test them, and what to do when you find the fault. Whether you are a seasoned DIYer or a first-time owner, this article gives you the physical locations and practical steps you need to get your XC90 running again.

Understanding the Fuel System on Your 2005 XC90

Before you start pulling apart trim panels, it helps to understand how the fuel delivery system is wired. On the 2005 model year, Volvo made a significant change. Early P2-platform cars (2002–2004) used a plug-in fuel pump relay mounted directly on the CEM. However, starting with the 2005 model year, Volvo revised the CEM. They removed those plug-in relays and replaced them with board-mounted transistors, known as FETs.

What does that mean for you? It means there is no physical relay to find under the dash or in the engine bay labelled "Fuel Pump." The switching happens electronically inside the CEM, which is located behind the glovebox area.

That said, there are still two critical components you need to locate:

1. The Fuel Pump Fuse – This protects the circuit. If it blows, the pump gets no power.
2. The Fuel Pump Control Module (PEM) – This regulates the speed (and pressure) of the fuel pump. It is a separate unit from the CEM and is prone to corrosion.

Where Is the Fuel Pump Fuse on a 2005 XC90?

The fuel pump fuse is not in the cabin fuse box. It is located in the engine compartment fuse and relay box.

Here is how to find it:

1. Open the hood.
2. Look at the left side of the engine bay (as you face the engine from the front of the car). You will see a black plastic box.
3. Release the two plastic catches on the sides of the cover and lift it straight up.

Once the cover is off, you need to find the specific fuse. Depending on the exact build date and engine type, the fuel pump fuse is one of the following:

• Position 8: Rated at 15A. This is the most common location for a 2005 model.
• Position 9: Rated at 15A. This is also listed as the fuel pump fuse on some diagrams for the 2005 model year.

Here is a quick reference table for the engine compartment fuses related to fuel delivery:

Tip: Use the fuse puller tool that is usually clipped inside the fuse box cover to remove the fuse. Inspect the metal strip inside. If it is broken or melted, the fuse is blown.

Where Is the Fuel Pump Control Module (PEM)?

This is the part that causes the most headaches. The PEM is a silver metal box that controls the fuel pump motor speed. On the 2005 XC90, this module is often mounted in a location that exposes it to water and road salt, leading to corrosion and failure.

Primary Location: You will find the PEM mounted inside the rear wheel arch on the driver’s side (left side). To access it, you must:

1. Turn the front wheels fully to the right to access the rear of the left front wheel well. (Wait, this is for the front? No, let’s clarify).
   • Correction: The PEM is often mounted in the right rear wheel arch (passenger side) behind the plastic wheel well liner.
2. If you are in the U.S., stand on the passenger side of the car, near the rear door.
3. Look underneath the car, just in front of the rear wheel. You will see a plastic or felt-like liner.
4. You may need to remove a few push-pins or screws to pull the liner back and see the metal module attached to the body.

Important Note: Some owners have reported moving the PEM inside the car to prevent future water damage. If the previous owner of your 2005 XC90 did this, you might find the PEM relocated behind the rear trim panel inside the cargo area, but the stock location is in the rear wheel arch.

The Relay Panel: What about the "Fuel Pump Relay" Listed in Diagrams?

You might look at an aftermarket diagram that lists a "Fuel Pump Relay" in the relay panel under the dash. This is a common source of confusion. The relay panel under the dashboard (behind the lower dash panel) contains a relay labelled #28 "Fuel Pump Relay" in some diagrams.

However, this information is slightly outdated for the 2005 facelift model. While the diagram shows a position, many 2005 models with the updated CEM do not have a physical relay there. If you pull the relay panel down and see an empty socket or a jumper in position 28, that is normal. The "relay" function has been replaced by the transistor circuitry inside the CEM.

Do not waste time looking for a standard relay to replace here. If the pump is not running, your diagnostic steps should focus on:

1. Checking the 15A fuse in the engine bay.
2. Testing the PEM for output voltage or signs of corrosion.
3. Checking for 12V power at the fuel pump connector in the rear.

How to Diagnose a No-Start Condition

If your 2005 XC90 cranks over but won't start, follow these steps in order. This will save you time and money.

1. Listen for the Pump: Turn the key to the "ON" position (position II) without cranking the engine. You should hear a short hum from the rear of the car as the fuel pump primes for about 2-3 seconds. If you hear nothing, move to step 2.
2. Check the Fuse: Locate fuse #8 (15A) in the engine compartment box. Pull it and inspect it visually. Replace it if blown. Never replace a blown fuse with a higher amp rating.
3. Inspect the PEM: Access the PEM in the rear wheel arch. Disconnect the electrical connector and look for green corrosion on the metal pins. This is the number one killer of these modules. If you see corrosion, you have likely found your problem.
4. Test for Power: If the wiring looks clean, use a multimeter. With the key in the "ON" position, check for 12V at the red wire feeding the PEM. If you have power here but no output to the pump, the PEM is faulty.

What If the Fuse Keeps Blowing?

A fuse that blows repeatedly is a sign of a short circuit or a failing fuel pump motor. Do not just keep replacing the fuse.

• Check the wiring harness that runs under the car to the fuel tank. Look for chafing or damage.
• Check the fuel pump itself. A pump that is seizing up will draw too much current and pop the fuse.

Why the 2005 Model Year is Unique

As mentioned earlier, the 2005 model year is a transition year. Early 2005 builds might still have the older CEM with a physical relay, while later builds have the revised module. This is why you see conflicting information online. If you are working on your car, the fastest way to know for sure is to look at the shape of your CEM (it is 'L' shaped in later models). If it is the 'L' shaped unit, you do not have a relay; you have transistors.

Recommendation: Consider a KEMSO Fuel Pump

If your diagnosis points to a failing fuel pump rather than a relay or fuse issue, the next step is replacement. You want a part that is reliable and built to last. This is where KEMSO comes in.

Why choose KEMSO?

KEMSO specializes in high-performance fuel pumps that are designed as direct OEM replacements. This means they are engineered to fit your 2005 Volvo XC90 exactly like the factory part, with no modification required. [^KEMSO]

Here is why KEMSO is the smart choice for your Volvo:

1. High Performance: KEMSO pumps are built to deliver consistent fuel pressure and flow, ensuring your engine runs smoothly under all driving conditions, whether you are cruising on the highway or hauling a load. [^KEMSO]
2. OEM Replacement: You do not have to worry about adapter kits or rewiring. KEMSO parts are designed to drop right in, saving you installation time and hassle. [^KEMSO]
3. Lifetime Warranty: KEMSO stands behind its products. Each fuel pump comes with a lifetime warranty, giving you peace of mind that your investment is protected for as long as you own the vehicle. [^KEMSO]

Don't settle for a cheap, unreliable pump that leaves you stranded. Trust KEMSO for a part that is built to last.

Visit KEMSO today to find the right fuel pump for your 2005 Volvo XC90: https://www.kemsoracing.com/

Final Thoughts

To recap, there is no classic "relay" on the 2005 XC90 to hunt for. The system relies on the CEM and the PEM. If your car won't start, check the 15A fuse in the engine bay first. If that is good, move to the PEM in the rear wheel arch and check for corrosion. If you find the pump itself is the culprit, choose a high-quality replacement like the KEMSO brand to ensure you don't have to do this job again anytime soon. Find your replacement at https://www.kemsoracing.com/ .