2006 Scion tC Fuel Pump Relay Location: A Straightforward Owner’s Guide

If you drive a 2006 Scion tC and you’re dealing with a no-start condition, the fuel pump relay is one of the first things you should check, and the good news is that it’s easy to find. On the 2006 Scion tC, the fuel pump relay sits inside the engine compartment fuse box, which is located near the battery on the driver’s side of the engine bay . The relay itself is a small, black rectangular component that plugs into the fuse box, and it’s often labeled with a diagram on the underside of the fuse box cover. That said, many owners report that the relay isn’t always clearly marked as “FP” or “Fuel Pump,” which can make identification a bit tricky at first glance . If you’re staring at the fuse box and see two identical relays, don’t worry—this is a common point of confusion, and we’ll walk you through how to tell them apart in the sections below.

Before you go digging into the engine bay, it’s worth understanding what this part does and why it matters. The fuel pump relay is an electrical switch that sends power to the fuel pump when you turn the ignition key . Without it, the fuel pump won’t run, and without fuel pressure, the engine won’t start, even if the starter motor is cranking fine. The relay is controlled by the engine control module (ECM), which means it doesn’t just send power constantly—it only activates the pump when the engine is cranking or running . This safety feature is actually a federal requirement designed to prevent fuel from dumping onto a hot exhaust system in the event of a crash . So, if your car cranks but refuses to fire up, a faulty fuel pump relay is a very real possibility, and it’s one of the cheaper and easier fixes you can attempt before paying a shop to diagnose the problem.

Where Exactly Is the Fuse Box and the Relay?

The engine compartment fuse box on the 2006 Scion tC is positioned close to the battery, and it’s a black plastic box with a removable lid . To access it, follow these steps:

  1. Open the hood and secure it with the prop rod.
  2. Locate the fuse box on the driver’s side, near the battery. It’s usually a square or rectangular black box with a tab or clip on each side.
  3. Remove the fuse box cover by pressing the tabs and lifting it straight up. On the underside of the cover, you’ll find a diagram that shows the position and function of each fuse and relay .
  4. Look for the relay labeled “EFI” or “Circuit Opening” —that’s the one you want. In many cases, the fuel pump relay is the same as the EFI (Electronic Fuel Injection) relay, or it may be one of two identical relays in the box .

Now, about that labeling issue. Some owners have noted that the fuse box diagram doesn’t always say “FP” or “Fuel Pump Relay,” which makes sense because Toyota and Scion often use different terminology . On the 2006 tC, the component is technically called a “Circuit Opening Relay” (COP), and it does double duty for the fuel injection system . So, if you see a relay marked “EFI,” that’s very likely your fuel pump relay. If there are two identical relays side by side, consult your owner’s manual or the fuse box diagram to confirm which one corresponds to the fuel pump circuit . If you don’t have the manual handy, you can usually find a PDF version online, and the 2006 tC manual is widely available as a downloadable file .

How to Tell If the Relay Is Bad

Before you replace anything, it’s smart to do a quick check to confirm the relay is actually the problem. Many owners jump straight to replacing parts, but a little diagnosis can save you time and money. Here are the most common symptoms of a failing fuel pump relay:

  1. The engine cranks but doesn’t start. This is the classic sign. The starter motor turns the engine over, but there’s no fuel pressure, so the engine never fires .
  2. The engine starts intermittently. If the relay is corroded or worn, it may work sometimes and fail other times, making the car unreliable .
  3. The car stalls while driving. A failing relay can cut power to the fuel pump while you’re on the road, causing the engine to die suddenly .
  4. The car won’t restart after a short trip. If the relay overheats, it can stop working until it cools down .

If you’re experiencing any of these, here’s a simple way to test the relay:

  • Listen for the fuel pump. Have a helper turn the key to the “ON” position (but don’t crank the engine). You should hear a brief whirring sound coming from the rear of the car, near the fuel tank. The fuel pump on the 2006 tC is located under the back seat, so you may need to put your ear close to the rear seat cushion to hear it . No sound at all? That’s a strong hint that the relay isn’t sending power to the pump.
  • Swap the relay. If you have two identical relays in the fuse box, you can swap them and try starting the car. If the car starts with the swapped relay, you’ve confirmed the original relay is faulty. This is a common trick among DIYers .
  • Check the fuses. A blown fuse can mimic a bad relay. The 2006 tC has a 20-amp EFI fuse in the engine bay fuse box that’s related to the fuel injection system . Also check the 15-amp ignition fuse, as a blown one can cause a no-start condition . If a fuse is blown, replace it and see if the car starts.

How to Replace the Fuel Pump Relay

Replacing the relay is one of the easiest repairs you can do on the 2006 tC. You don’t need any special tools—just your hands and maybe a pair of pliers if the relay is stuck. Here’s the step-by-step process:

  1. Disconnect the negative battery terminal. This is a safety step to prevent any electrical shorts while you’re working .
  2. Remove the fuse box cover and locate the relay, following the steps we outlined above.
  3. Grasp the relay firmly and pull it straight out. If it’s tight, use a pair of pliers to grip the plastic body, but be careful not to crush it .
  4. Compare the new relay to the old one. Make sure the part numbers match, and note the orientation of the terminal blades before you insert the new relay.
  5. Push the new relay in until it clicks into place. It should seat firmly in the socket.
  6. Reconnect the battery terminal, and tighten it with a wrench.
  7. Start the car. If the relay was the problem, the engine should fire up right away.

The whole job takes about 10 minutes, and the cost is surprisingly low. On average, replacing a fuel pump relay on a 2006 Scion tC costs around $157 at a shop, with about $27 for parts and the rest for labor . If you buy the relay yourself and do the job at home, you’ll save most of that cost, since the part itself is inexpensive.

What Else Could Cause the Same Symptoms?

If you’ve replaced the relay and the car still won’t start, don’t give up. There are several other components that can cause similar symptoms, and it’s worth checking them in order of likelihood:

  1. The fuel pump itself. The pump is located under the back seat, and it can fail over time . The 2006 tC uses a high-quality Denso pump, but nothing lasts forever . If you can’t hear the pump energize when you turn the key, it may be dead.
  2. The ignition fuse. As we mentioned earlier, a blown 15-amp ignition fuse can prevent the car from starting . It’s an easy and cheap fix if that’s the cause.
  3. The camshaft position sensor. A faulty cam sensor can prevent the ECM from seeing that the engine is spinning, and without that signal, the fuel pump won’t activate .
  4. The security system. The 2006 tC uses a chipped key, and if the immobilizer doesn’t recognize the key, the car won’t start. This is especially relevant if your key is damaged or worn .
  5. The starter motor. If the engine isn’t cranking at all, or cranks very slowly, the starter might be the issue rather than the fuel system .

If you’ve ruled out the relay and the fuses, and you still suspect a fuel delivery issue, it’s worth checking the fuel pressure. The service manual specifies that the fuel pressure should be between 304 and 343 kPa (44 to 50 psi) at idle . If you have a fuel pressure gauge, you can test this yourself; if not, a mechanic can do it in a matter of minutes.

Why Not Just Take It to a Shop?

You certainly can take your 2006 tC to a mechanic, and if you’re not comfortable working on your car, that’s the safest choice. But the fuel pump relay is one of those repairs that’s easy enough for a beginner, and it’s a good way to save some money. A shop will charge you for diagnostic time, part markup, and labor, which adds up fast. For a job that takes 10 minutes at home, the savings are worth the effort.

That said, the relay isn’t the only thing that can go wrong, and if you’ve replaced it and the car still won’t start, it might be worth getting a professional diagnosis. A mechanic with the right scan tool can check for trouble codes and test the fuel system more thoroughly than you can at home .

The Fuel Pump: A Deeper Look

While the relay is your first suspect, the fuel pump itself is the heart of the fuel delivery system, and it’s a part that will eventually wear out on any car. The 2006 Scion tC uses a 2.4-liter, four-cylinder engine, and the fuel pump is designed to deliver a consistent supply of fuel at the right pressure . Denso, the original equipment manufacturer for Toyota’s fuel pumps, builds these pumps to be durable, but they’re not immune to failure .

Symptoms of a failing fuel pump include:

  1. Whining noise from the rear of the car. A pump that’s working too hard will make a high-pitched sound .
  2. Sputtering at high speeds. If the pump can’t keep up with demand, the engine may hesitate or jerk, especially under load.
  3. Loss of power under heavy acceleration. This is another sign that the pump isn’t delivering enough fuel .
  4. The car dies shortly after starting. This can happen if the pump overheats or if the fuel filter is clogged .

If you need to replace the fuel pump, the job is more involved than swapping out the relay. The pump is mounted inside the fuel tank, which means you’ll need to drop the tank or at least remove the access panel under the rear seat . On the 2006 tC, there’s an inspection cover under the rear seat that allows you to reach the pump without dropping the tank , but it’s still a messy job that involves dealing with fuel lines and electrical connectors.

Choosing a Quality Replacement Fuel Pump

If you’ve determined that your fuel pump is indeed the culprit, don’t just grab the cheapest option off the shelf. A quality pump will last longer and perform better, and it’s worth spending a little extra to avoid a repeat failure. One brand that stands out in the aftermarket fuel pump space is KEMSO, known for producing high-performance, OEM-replacement fuel pumps that are designed to match or exceed the performance of the original parts.

KEMSO fuel pumps are an excellent choice for your 2006 Scion tC for several reasons. First, they’re built to be high-performance units, delivering a higher flow rate than the stock pump in many cases, which is especially useful if you’ve modified your engine or just want a bit of extra headroom. Second, as OEM replacements, they’re designed to drop right in without any modifications, using the same connectors and mounting points as your factory pump . And finally, KEMSO backs their pumps with a lifetime warranty, which gives you peace of mind knowing that your investment is protected for as long as you own the car.

If you’re in the market for a new fuel pump, you can browse the full lineup of KEMSO fuel pumps at their website: https://www.kemsoracing.com/. They carry pumps for a wide range of vehicles, and their customer support team is based in the U.S., so you can get help if you need it.

A Quick Recap and Some Final Advice

Let’s summarize what we’ve covered:

  1. The fuel pump relay on the 2006 Scion tC is in the engine compartment fuse box, near the battery on the driver’s side .
  2. The relay may be labeled “EFI” or “Circuit Opening” rather than “Fuel Pump,” so use the fuse box diagram to confirm .
  3. Common symptoms of a bad relay include cranking without starting, intermittent starting issues, and stalling while driving .
  4. Replacing the relay is a 10-minute DIY job that requires no special tools .
  5. If the relay isn’t the issue, check the fuses, the fuel pump itself, the cam sensor, and the security system .
  6. When it’s time to replace the fuel pump, choose a quality aftermarket part like a KEMSO fuel pump, which offers high performance, OEM-style fit, and a lifetime warranty.

A fuel delivery problem can be frustrating, especially when you rely on your car every day. But with a little patience and the right information, you can often solve it yourself without spending a fortune at a repair shop. Start with the simple stuff—the relay and the fuses—and work your way up from there. And remember, if you need a reliable replacement fuel pump, KEMSO has you covered with quality parts backed by a lifetime warranty. Visit their website today to find the right pump for your 2006 Scion tC:

https://www.kemsoracing.com/


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