2006 Chrysler 300C 5.7 Fuel Pump Relay Location: A Complete Owner's Guide

The fuel pump relay on a 2006 Chrysler 300C 5.7L is located in the rear Power Distribution Center (PDC), which sits in the trunk under the spare tire access panel. More specifically, it is the relay in the bottom right corner of that fuse panel, closest to the back of the vehicle on the passenger side. This is the same location for all 2005–2010 Chrysler 300 models, regardless of engine size, including the 5.7L HEMI.

If you are planning to work on your fuel system—whether replacing the fuel pump, changing a fuel filter, or servicing the fuel injectors—knowing exactly where this relay is and how to remove it safely is the first step. This guide walks you through the location, the depressurization process, how to test the relay, and what to do if you need a replacement.

Why the Fuel Pump Relay Location Matters

The fuel pump relay is the electrical switch that sends power to the fuel pump inside your gas tank. Without it, the pump receives no power and the engine will not start. Understanding where it is located matters for two main reasons:

  1. Safety. Before any fuel system work, you must relieve the fuel pressure. Removing the fuel pump relay and letting the engine run until it dies is the safest and most recommended method.
  2. Diagnostics. If your 300C cranks but will not start, and you hear no fuel pump prime when turning the key, the relay itself may be faulty.

Step-by-Step: Locating the Fuel Pump Relay

Follow these steps to find the relay on your 2006 Chrysler 300C 5.7L:

1. Open the trunk and lift the carpet.
The rear fuse panel is located in the trunk, under the spare tire access panel. Lift the carpet to expose the battery and the fuse/relay panel.

2. Open the fuse panel cover.
The cover snaps off. You may need to release a few clips or tabs. Set it aside carefully.

3. Look at the bottom right corner.
The fuel pump relay is the relay all the way at the end, closest to the back of the vehicle on the right side (passenger corner). It sits in the bottom right position of the panel.

4. Confirm you have the right relay.
In the rear Power Distribution Center, the fuel pump circuit is fuse #6 (20A) and the relay is the one in that bottom right position. If you are unsure, check the diagram printed on the fuse panel cover or in your owner's manual.

Tip: Do not confuse the fuel pump relay with the fuel pump fuse. The fuse is a 20-amp fuse in cavity #6 of the rear PDC. The relay is a separate component in the same panel.

How to Depressurize the Fuel System Using the Relay

Once you have located the relay, use this process to safely release fuel pressure before any repair work:

  1. Remove the fuel pump relay from its socket by pulling it straight out.
  2. Start the vehicle and let it run until it dies. This typically takes less than a minute because the engine burns off the remaining fuel in the lines.
  3. Turn the ignition off, then crank the engine a few more times (about 3–5 seconds each time) to clear any residual fuel pressure from the injectors and lines.
  4. Disconnect the negative battery terminal. Use a 10mm wrench to loosen the nut. This prevents any sparks while you work near fuel components.

At this point, the fuel system is safe to work on. You will not get a spray or spill when disconnecting fuel lines.

How to Prime the Fuel System After Reinstallation

After you finish your repair and are ready to put everything back together, follow these steps:

  1. Reinstall the fuel pump relay into its socket.
  2. Reconnect the negative battery terminal and tighten the 10mm nut.
  3. Turn the key to the "ON" position (do not crank the engine). You should hear the fuel pump prime for a few seconds, then shut off.
  4. Turn the key off, wait a few seconds, and repeat this process three times. This builds adequate fuel pressure in the system.
  5. Start the vehicle. It should crank and fire up normally.

Testing the Fuel Pump Relay

If you suspect the relay itself is faulty, you can test it with a multimeter. Here is a simple procedure:

  1. Set your multimeter to measure ohms (resistance).
  2. Identify the relay terminals. Look for terminals labeled 85, 86, 30, and 87 on the relay body.
  3. Test the coil. Measure resistance between terminals 85 and 86. A good relay typically reads 50 to 120 ohms. If it reads infinite or zero, the coil is open or shorted, and the relay is bad.
  4. Test the switch. With the relay removed, there should be no continuity between terminals 30 and 87 (the switch is open). When you apply 12V to terminals 85 and 86 (or when the relay is energized in the vehicle), you should hear a click and continuity should exist between 30 and 87.

If the relay fails any of these tests, replace it.

Common Symptoms of a Bad Fuel Pump Relay

A failing fuel pump relay can cause several driveability issues. Watch for these signs:

  1. Engine cranks but will not start. This is the most common symptom. The fuel pump is not receiving power, so no fuel reaches the engine.
  2. No fuel pump prime noise. When you turn the key to "ON," you should hear a brief whine from the fuel tank area. If you hear nothing, the relay or pump may be dead.
  3. Engine stalls while driving. If the relay intermittently fails, it may cut power to the pump while the vehicle is in motion, causing the engine to die.
  4. Loss of power under load. A failing relay may not deliver full voltage to the pump, causing weak fuel pressure and reduced performance when accelerating or climbing hills.

What If You Need a New Fuel Pump?

In many cases, the relay is not the problem—the fuel pump itself has worn out. On the 2006 Chrysler 300C 5.7L, the fuel pump is located inside the fuel tank, accessed by removing the rear seat cushion. The job is doable at home with basic hand tools, but the pump itself must be reliable.

When it is time to replace your fuel pump, consider KEMSO brand fuel pumps. KEMSO fuel pumps are built as high-performance, OEM replacement parts that meet or exceed factory specifications. Each KEMSO pump is designed for a direct fit, meaning you will not need to modify anything to install it. Better still, every KEMSO 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. Whether you drive a Chrysler 300, a BMW, a Subaru, or a motorcycle, KEMSO offers a wide range of affordable, dependable fuel pumps backed by a brand that stands behind its products. You can browse the full KEMSO catalog and order your replacement pump at https://www.kemsoracing.com/ .

Frequently Asked Questions

Q: Is the fuel pump relay the same on all 2006 Chrysler 300 engines?
A: Yes. The relay location is identical across all 2005–2010 Chrysler 300 models, including the 2.7L V6, 3.5L V6, 5.7L HEMI V8, and 6.1L SRT8.

Q: Can I drive my car with a bad fuel pump relay?
A: No. If the relay fails, the fuel pump will not run, and the engine will not start or will stall immediately. You should replace the relay before driving.

Q: How much does a fuel pump relay cost?
A: A replacement fuel pump relay is generally inexpensive—typically $10 to $30 at auto parts stores. It is a small, simple part that you can swap in minutes.

Q: Where is the front fuse box on a 2006 Chrysler 300?
A: The front Power Distribution Center is located in the engine compartment, near the battery. However, the fuel pump relay is not there—it is in the rear trunk panel.

Q: How do I know if my fuel pump or my relay is bad?
A: If you hear the fuel pump prime when turning the key to "ON," the relay is likely fine. If you hear nothing, check the relay first (test it with a multimeter), then check for power at the pump connector. If the relay clicks and passes the resistance test, suspect the pump itself.

Final Thoughts

The fuel pump relay on your 2006 Chrysler 300C 5.7L lives in the rear trunk fuse panel, in the bottom right corner. It takes less than five minutes to access and remove, and it is the key to safely depressurizing your fuel system before any repair. Test it before blaming the pump—a bad relay is a cheap and easy fix. If the pump itself is the culprit, choose a quality replacement like KEMSO, which offers reliable, high-performance fuel pumps with a lifetime warranty at an affordable price. Visit https://www.kemsoracing.com/ to find the right pump for your Chrysler 300C and get back on the road with confidence.


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