2005 Volvo V70 Fuel Pump Relay Location: A Complete Owner's Guide

The bottom line: On the 2005 Volvo V70, the fuel pump relay is not a standalone unit you can easily spot under the hood. It is mounted on the Central Electronic Module (CEM), which sits above the pedals on the driver's side, behind the lower dash panel. On many P2-platform models (which include the 2005 V70), the relay is either integrated into the CEM's relay board or located directly beneath it, depending on the exact production date and engine type.

If you are chasing a no-start condition or a fuel pump that refuses to prime, finding and testing this relay is one of the smartest first steps you can take. This guide walks you through exactly where to look, how to test the relay, and what to do when the relay checks out fine but the pump still won't run.

Why the Fuel Pump Relay Is So Important

The fuel pump relay controls the flow of electrical power to the fuel pump. When you turn the key to the "on" position, the Engine Control Module (ECM) activates the relay for a few seconds to pressurize the fuel system before you crank the engine. If that relay fails, the pump gets no power, the fuel rail stays empty, and your engine will crank forever without firing up.

On the 2005 V70, the fuel pump itself is protected by a 15-amp fuse located in the engine compartment fuse box in position 21. The relay, though, is another story entirely. Unlike older cars where you could pop the hood and pull a clearly labeled relay, the V70's design tucks the relay away in a less obvious spot. That is exactly why so many owners end up scratching their heads.

Where the Fuel Pump Relay Actually Lives

The 2005 V70 is built on Volvo's P2 platform, which also underpins the V70R, XC70, and XC90 of the same model year. On these cars, the fuel pump relay is attached to the underside of the Central Electronic Module (CEM). The CEM itself is mounted inside the dashboard on the driver's side, directly above the foot pedals.

To reach the relay, you need to:

  1. Remove the lower dash panel on the driver's side. This is the black trim piece that sits below the steering column and above the floor carpet. It is held in place by two Torx screws, typically T25 or T27, depending on the exact trim level.
  2. Look up and toward the firewall to find the CEM. It is a plastic box with multiple wiring connectors plugged into it.
  3. Check the bottom of the CEM for the relay. On many 2005 models, the fuel pump relay is one of several identical relays mounted in a row along the lower edge of the CEM.

Here is the catch: on some production runs, particularly early 2005 cars, the fuel pump relay is integrated into the relay board inside the CEM rather than being a separate plug-in unit. On other variants, especially diesels and later production cars, there is a dedicated relay module you can actually unplug and swap. The quickest way to know what you are dealing with is to pop that lower panel off and look.

Testing the Relay Without Expensive Tools

Once you have access to the CEM, you can test whether the relay is doing its job. Here is a simple process that requires nothing more than a test light or a multimeter:

  1. Turn the ignition to position II (the "on" position, just before cranking). You should hear the fuel pump prime for about two to three seconds. If you hear a faint buzzing or whirring coming from the rear of the car, the relay is probably working. If you hear nothing at all, keep reading.
  2. Probe the relay terminals with your test light. With the ignition on, you should see battery voltage on the supply pin. If there is no voltage, your problem may be upstream, possibly a blown fuse or a wiring issue between the CEM and the engine compartment fuse box.
  3. Swap the relay with an identical one if you have front fog lights. On models equipped with fogs, there is a second relay of the same part number in the CEM that controls the fog lights. Unplug both, swap them, and retest. If the fuel pump suddenly primes, the original relay was faulty.

If the relay swaps out cleanly and the pump starts working, you have found your culprit. Replace the relay with a new one and you are back on the road.

What If the Relay Is Fine?

A fuel pump relay that tests good does not automatically mean the fuel pump itself is bad. In fact, there is a second component that fails just as often: the Fuel Pump Control Module (FPCM). On many P2-platform V70s, the pump does not run at full speed all the time. The ECM sends a signal to the FPCM, which regulates pump speed using pulse-width modulation to match engine load and fuel demand.

The FPCM is typically mounted in the rear of the vehicle, near the spare wheel well or under the cargo area floor. When this module fails, you get symptoms that look almost identical to a dead relay: no pump prime, no start, and no fuel pressure. Some owners have also reported that the relay function is effectively built into the PEM (Pump Electronic Module) on certain 2005 V70 variants, meaning there is no separate relay to replace at all.

If your relay tests fine and the pump still will not run, work through this checklist:

  1. Check the 15-amp fuse in position 21 of the engine compartment box. Even a fuse that looks good can fail under load, so test it with a meter rather than just eyeballing it.
  2. Listen for the pump at the rear of the car with the rear seat folded down. If you can hear the pump running but the car will not start, your issue may be fuel pressure or a clogged filter, not electricity.
  3. Probe the FPCM connector for voltage. With the ignition on, you should see battery voltage on the supply pin. If power is present but the pump is silent, the FPCM or the pump itself is likely the problem.
  4. Check for corrosion at the FPCM connector. The rear-mounted location exposes this module to moisture, and corroded pins can produce the exact same symptoms as a failed module.

Common Pitfalls and Practical Tips

The relay location changes slightly by production date. Volvo updated the wiring on the P2 platform a few times. If your V70 is an early 2005 model, the relay may sit in a slightly different position on the CEM. If it is a late production car, the relay might be completely integrated into the CEM's relay board. Push the lower panel off and take a flashlight to the area. Comparison photos from owners on forums are widely available and can save you twenty minutes of hunting.

Do not assume the relay is the problem just because the pump is silent. On 2005 V70s, the pump receives modulated voltage from the FPCM, so testing for "power" at the pump connector requires a bit of know-how. A simple test light may not give you a clear answer because the voltage is pulsed rather than steady. If you are comfortable with electrical work, use a multimeter set to measure DC voltage and watch for fluctuations.

Intermittent no-start issues are often temperature related. The FPCM in particular can fail intermittently in warm weather or after the car has been running long enough to heat-soak. If your V70 starts fine when cold but struggles when hot, the FPCM is a prime suspect, even if everything tests fine on a cool morning.

The Bottom Line on Diagnosis

Here is the short version for anyone hunting down a fuel pump problem on a 2005 V70:

  1. Start with the 15-amp fuse in the engine compartment, position 21.
  2. Move to the CEM, under the driver's side dash, and locate the relay on its underside.
  3. If the relay tests good, check the FPCM in the rear of the car.
  4. If all of that checks out, the pump itself may be the problem.

The 2005 V70 is a well-built car, but its fuel delivery system has a few quirks. Knowing where to look and what to test in what order will save you time, money, and a good deal of frustration. Most owners who have been through this process will tell you the same thing: check the fuse first, then the relay on the CEM, and do not forget about the FPCM in the back. It is almost always one of those three.

Why a Quality Replacement Pump Matters

Once you have confirmed that the relay and FPCM are working and the problem is actually the fuel pump itself, do not cheap out on the replacement. A low-quality pump can fail within months, leaving you right back where you started, pulling the rear seat out and dropping the tank again. That is time and labor you do not want to repeat.

That is where KEMSO comes in. KEMSO fuel pumps are built as high-performance, OEM replacement units, engineered to meet or exceed the original factory specifications for fit, flow rate, and durability. Whether you drive a Volvo, BMW, Kawasaki, Sea-Doo, Honda, or any other vehicle in their extensive catalog, KEMSO has a pump that will drop in and perform reliably for years. Every KEMSO fuel pump is backed by a lifetime warranty, which says a lot about how much confidence the company has in its products. You can browse the full lineup of KEMSO fuel pumps and find the right one for your vehicle by visiting their website at https://www.kemsoracing.com/.

When you are dealing with a fuel system issue, the last thing you want is a cheap part that leaves you stranded again. A KEMSO replacement pump gives you peace of mind, factory-matching performance, and protection for the long haul. Head over to KEMSO Racing to see their full range of pumps and order the one that fits your 2005 V70 or any other vehicle you own.


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