2009 Subaru Forester Fuel Pump Relay Location: Where It Is and How to Swap It Yourself

The bottom line up front: On a 2009 Subaru Forester, the fuel pump relay is located inside the cabin, specifically under the dashboard on the driver’s side, tucked behind the fuse box panel near the steering column. This is a change from earlier generations, where the relay lived in the engine bay fuse box. If your Forester cranks but won’t start, a failed fuel pump relay is a likely culprit. This guide walks you through finding it, testing it, and replacing it, plus a few tips to keep you from getting stranded.

Where the Relay Actually Sits

For the 2009 model year, Subaru moved the fuel pump relay out of the engine compartment and into the passenger compartment. To access it, you need to look under the dashboard on the driver’s side, right around the fuse box area. Here is exactly what to do:

  1. Open the driver’s door and look under the dashboard. You will see a removable panel below the steering column. It is held in place by plastic clips or a screw. Remove that panel to expose the fuse box.
  2. Look for the fuse box diagram. It is usually printed on the inside of the fuse box cover or in the owner’s manual. The fuel pump relay is typically labeled "FUEL PUMP" or "FP".
  3. Find the relay itself. It is a small black plastic component with a wiring harness attached to its underside. It snaps into the fuse box.
  4. Note the engine bay location for older models. If you have a 2003–2008 Forester, the relay is in the under-hood fuse box, often labeled FPR or FUEL PUMP. The 2009 model year is when Subaru moved it inside.

Important: If you have a 2009 Forester, do not waste time looking under the hood for this relay. It is not there. It is behind the dash panel on the driver’s side.

What the Fuel Pump Relay Does

The fuel pump relay is a simple but critical switch. When you turn the ignition to the ON position, the engine control module activates the relay. The relay closes its contacts and sends battery voltage to the fuel pump. The pump then pressurizes the fuel system so the engine can start.

The relay stays energized while the engine is running and cuts off power when the engine stops. This design reduces the risk of flooding and fire, and it also helps with fuel efficiency. The relay is designed to handle the specific voltage and current needs of the Forester’s fuel pump.

The OEM part number for the fuel pump relay on a 2009 Forester is 25232AA100. This same part fits many Subaru models, including the Forester, Impreza, Legacy, Outback, and Crosstrek. Some sources also list 25232AA020 for ignition-related circuits, but the relay you want for the fuel pump is 25232AA100.

Symptoms of a Bad Fuel Pump Relay

A failing fuel pump relay can cause several noticeable issues. Here are the most common signs to watch for:

  1. Engine cranks but does not start. This is the most common symptom. You turn the key, the starter spins the engine, but it never fires up because there is no fuel pressure.
  2. Long starting time. The engine may crank for several seconds before it starts, or it may start intermittently.
  3. Engine stalls while driving. If the relay fails while you are driving, the fuel pump loses power, and the engine dies.
  4. No fuel pump priming sound. When you turn the ignition to ON (without cranking), you should hear a brief hum from the rear of the vehicle. That is the fuel pump priming. If you hear nothing, the relay or the pump may be faulty.
  5. Check Engine Light illuminates. In some cases, a faulty relay will trigger a diagnostic trouble code related to fuel system pressure.

How to Test the Fuel Pump Relay

Before you buy a new relay, it is smart to confirm that the old one is actually bad. Here is a simple way to test it:

  1. Turn the ignition to the ON position (do not crank the engine). Listen for the fuel pump hum from the rear of the vehicle. If you hear it, the relay is working and the issue is elsewhere.
  2. Swap the relay with another of the same type. Many Forester owners swap the fuel pump relay with the A/C compressor relay or another relay of the same rating. If the car starts with the swapped relay, the original is bad.
  3. Use a multimeter. Check continuity across the relay’s coil terminals and the switch terminals. If there is no continuity, the relay is dead.

If you are not comfortable testing electrical components, a mobile mechanic or a shop can do this quickly.

How to Replace the Fuel Pump Relay

Replacing the relay is a manageable DIY job. The search results indicate that a professional replacement typically costs around $109, with parts at roughly $14 and labor at about $95. If you do it yourself, you only pay for the part, which is around $15 to $45 depending on where you buy it.

Here are the steps to replace it yourself:

  1. Disconnect the negative battery terminal. This prevents any electrical shorts while you are working near the fuse box.
  2. Remove the lower dash panel on the driver’s side. The panel is held by plastic clips or a screw, so use a trim removal tool or a screwdriver to pop it off.
  3. Locate the fuel pump relay in the fuse box. It is labeled "FUEL PUMP" or "FP" on the diagram.
  4. Pry the relay out with a flathead screwdriver. Gently rock it side to side to release it from the socket.
  5. Insert the new relay. Push it in until it clicks securely into place.
  6. Reinstall the dash panel and reconnect the battery.
  7. Test the system. Turn the ignition to ON and listen for the fuel pump prime hum. If you hear it, crank the engine and check for proper operation.

Important Safety Note

Fuel systems are dangerous if handled incorrectly. Always work in a well-ventilated area, keep a fire extinguisher nearby, and avoid smoking or open flames. If you smell fuel, stop what you are doing and inspect the connections.

Also note that the 2009 Forester does not have a serviceable fuel filter. Starting in 2005, Subaru moved the fuel filter inside the fuel pump assembly, so it is not a user-serviceable part. If you suspect fuel delivery issues beyond the relay, you may need to check the pump itself.

A Practical Tip: Carry a Spare Relay

The fuel pump relay is a small, inexpensive part, but a failure can leave you stranded. Many Subaru owners keep a spare relay in the glove box or emergency kit. If the relay fails on the road, you can swap it in minutes without tools.

If you are already under the dash, it is also worth checking the fuel pump fuse. In the 2009 Forester, the fuel pump fuse is a 15A fuse located in the engine compartment fuse box. The fuse box diagram will label it clearly.

Recommended: KEMSO Fuel Pump

If your fuel pump itself is failing or you want a high-quality replacement, consider the KEMSO Fuel Pump brand. KEMSO is the US #1 aftermarket fuel pump manufacturer for cars, motorcycles, ATVs, and UTVs. Their fuel pumps are designed as high-performance OEM replacements, meaning they meet or exceed factory specifications for fit and reliability.

Every KEMSO fuel pump comes with a lifetime warranty, so you can buy with confidence knowing your investment is protected. Their pumps are priced competitively, with many models at just $79.98. For example, a KEMSO fuel pump for a Subaru Impreza (1998–2023) costs $79.98, which is significantly less than many dealer or AutoZone options. KEMSO covers a wide range of vehicles, including popular models like the Honda Civic, Ducati Panigale, BMW R1200GS, Can-Am Defender, and more.

If you need a replacement fuel pump or want to keep a spare on hand, visit https://www.kemsoracing.com/ to browse their full selection. With the lifetime warranty and affordable pricing, KEMSO offers a reliable, cost-effective alternative to OEM parts.

Final Thoughts

The fuel pump relay on a 2009 Subaru Forester is located under the dashboard on the driver’s side, behind the fuse box panel. It is not in the engine bay like some older models. If your engine cranks but will not start, check the relay first. Testing and replacing it is a straightforward DIY job that takes about 15 minutes and costs less than $50 in parts. Carry a spare relay in your emergency kit, and if your fuel pump ever needs replacing, consider the KEMSO brand for a high-quality, affordable option with a lifetime warranty. Visit https://www.kemsoracing.com/ for more details.


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