2002 Audi A6 Fuel Pump Relay Location: The Complete Guide to Finding and Replacing It Yourself

The bottom line: The fuel pump relay on a 2002 Audi A6 (C5 platform, 1997-2004) is located in the Micro Central Electric Panel, which is the relay carrier behind the driver's side storage compartment. It is relay position #4 and is labeled as relay J17. This is the most common location across all engine variants including the 1.8L turbo, 2.7L twin-turbo, 2.4L, 2.8L, 3.0L, and 4.2L V8 engines, as well as the 2.5L TDI diesel models.

If your 2002 Audi A6 cranks but refuses to start, or starts and then dies after a few seconds, a failing fuel pump relay is one of the most common causes. Many owners waste hours checking the fuel pump itself, only to find the problem is a simple $20 relay. This guide will walk you through exactly where to find the relay, how to test it, and what to do if it's bad.

Where Is the 2002 Audi A6 Fuel Pump Relay Located?

The 2002 Audi A6 fuel pump relay is mounted in the Micro Central Electric Panel (also called the relay carrier or main relay panel). This panel is located inside the cabin, on the driver's side of the dashboard, behind the storage compartment.

To access it, follow these steps:

  1. Open the driver's side door.
  2. Open the small storage compartment on the left side of the dashboard (next to the steering wheel).
  3. Squeeze the sides of the storage bin and pull it straight out. It will detach completely.
  4. Behind the storage compartment, you will see a metal bracket with a black plastic relay panel mounted to it.
  5. The relay panel has multiple relay positions. The fuel pump relay is in position #4.

According to the manufacturer's component identification chart for the 2002 Audi A6, the relay positions are:

  • Position 1: J4 Dual Horn
  • Position 2: J59 Load Reduction
  • Position 3: J555 Low Range Hydraulic Pump (Allroad only)
  • Position 4: J17 Fuel Pump
  • Position 5: J31 Wiper/Washer Intermittent
  • Position 6: J31 Wiper/Washer Intermittent

The relay itself is typically a black or brown rectangular relay with five pins. On some models, the relay is labeled with "J17" or "Fuel Pump" on the relay carrier.

What Does the Fuel Pump Relay Do?

The fuel pump relay (J17) is an electrical switch that controls power to the fuel pump (G6). When you turn the ignition key to the "on" position, the engine control unit (ECU) sends a signal to the relay coil, which closes the circuit and sends 12 volts to the fuel pump.

The relay is designed to only activate for a few seconds when the ignition is first turned on. This allows the fuel system to pressurize before the engine starts. Once the engine is running, the relay stays closed as long as the engine is cranking or running. If the engine stalls or the ignition is turned off, the relay opens and cuts power to the pump. This is a safety feature to prevent fuel from being pumped in a crash.

Symptoms of a Bad Fuel Pump Relay on a 2002 Audi A6

A failing fuel pump relay can cause a range of symptoms. Here are the most common signs:

1. Engine Cranks But Will Not Start
This is the most common symptom. You turn the key, the starter motor spins the engine, but the engine never fires. The fuel pump is not receiving power, so no fuel reaches the injectors. If you listen carefully near the rear of the car, you will not hear the fuel pump prime for 2-3 seconds when the key is first turned on.

2. Engine Starts Then Dies Immediately
Sometimes the relay works intermittently. The engine starts briefly on the fuel that was already in the lines, but then stalls because the relay fails to keep the pump running. This is a classic sign of a failing relay.

3. Intermittent Stalling While Driving
If the relay contacts are worn or dirty, the relay may lose connection while you are driving. The engine will suddenly die, and you will lose power steering and brakes. This is dangerous and should be addressed immediately.

4. No Fuel Pump Prime Noise
When you turn the ignition to the "on" position (without cranking), you should hear a faint whirring noise from the rear of the car for about 2 seconds. This is the fuel pump pressurizing the system. If you do not hear this noise, the relay is likely bad, or the fuel pump itself is dead.

5. Check Engine Light
In some cases, a bad fuel pump relay will trigger a check engine light. The ECU may store a code related to fuel pressure or fuel pump circuit issues.

How to Test the 2002 Audi A6 Fuel Pump Relay

Before you spend money on a new relay, it is smart to test the existing one. Here is a simple step-by-step process:

Method 1: Listen for the Fuel Pump Prime

  1. Turn the ignition key to the "on" position (do not crank the engine).
  2. Listen near the rear of the car, under the rear seat, or near the fuel tank.
  3. If you hear a 2-second whirring sound, the relay is working. If you hear nothing, the relay or the pump is bad.

Method 2: Swap the Relay

  1. Locate the relay panel behind the driver's side storage compartment.
  2. Pull out the fuel pump relay (position #4).
  3. Find a relay with the same part number (typically a 5-pin relay) in another position that controls a non-essential system, such as the horn relay (position #1) or the load reduction relay (position #2).
  4. Swap the relays. If the engine now starts and runs, the fuel pump relay was bad. The other system (like the horn) may stop working, but that confirms the diagnosis.

Method 3: Use a Multimeter

  1. Pull the fuel pump relay out of the panel.
  2. Set your multimeter to measure resistance (ohms).
  3. Measure across the coil terminals (typically pins 85 and 86). You should see a resistance reading between 50 and 120 ohms. If the reading is infinite (open circuit), the relay coil is burned out.
  4. Apply 12 volts to pins 85 and 86. You should hear a click, and the continuity between pins 30 and 87 should close. If not, the relay contacts are welded or stuck.

What About the Fuse?

The fuel pump relay is protected by a fuse. On the 2002 Audi A6, the fuel pump fuse is fuse #28 in the main fuse box on the left side of the dashboard. It is a 20-amp fuse.

If the fuse is blown, the relay will still click but no power will reach the pump. Always check the fuse first before replacing the relay. A blown fuse could indicate a shorted fuel pump or a wiring issue.

Fuel Pump Relay Location for Different Engine Types

The 2002 Audi A6 was available with several engine options. The fuel pump relay location is the same for all gasoline engines, but the diesel models have a slightly different setup.

Gasoline Engines (1.8L Turbo, 2.4L, 2.7L Twin-Turbo, 2.8L, 3.0L, 4.2L V8)
The fuel pump relay (J17) is in position #4 of the Micro Central Electric Panel, behind the driver's side storage compartment.

Diesel Engines (2.5L TDI, engine codes AYM)
The 2002 Audi A6 2.5L TDI diesel also uses a fuel pump relay (J17). It is located in the same relay panel, position #4. However, the diesel engine also has a separate fuel cooling pump relay (J445) and a fuel cooling pump fuse (S262) located in the engine compartment electronics box.

Allroad Models
The 2002 Audi A6 Allroad (with air suspension and off-road capability) uses the same relay panel. The fuel pump relay is still position #4. Position #3 is occupied by the low range hydraulic pump relay (J555), which is specific to manual transmission Allroad models.

How to Replace the 2002 Audi A6 Fuel Pump Relay

Replacing the fuel pump relay is one of the easiest repairs you can do on this car. You do not need any special tools.

What you need:

  • A replacement fuel pump relay (Audi part number 4B0 906 381 or equivalent)
  • Your hands

Steps:

  1. Open the driver's side door and remove the storage compartment on the left side of the dashboard.
  2. Locate the black relay panel.
  3. Identify position #4. The relay may be labeled "J17" or "Fuel Pump."
  4. Grasp the relay firmly and pull it straight out. It may require a gentle wiggle.
  5. Push the new relay into the same position until it clicks into place.
  6. Reinstall the storage compartment.
  7. Turn the ignition to the "on" position and listen for the fuel pump prime noise. If you hear it, the repair is successful.
  8. Start the engine and verify it runs smoothly.

Common Mistakes to Avoid

1. Replacing the fuel pump instead of the relay
Many owners assume the fuel pump itself is bad because the engine does not start. The fuel pump relay is much more common to fail than the pump itself. Always test the relay first.

2. Buying the wrong relay
The Audi A6 C5 uses a specific 5-pin relay. Do not use a generic 4-pin relay from a parts store. Check the part number on the original relay before buying a replacement.

3. Ignoring the fuse
A blown fuse #28 (20A) will cause the same symptoms as a bad relay. Check the fuse before replacing the relay.

4. Not checking for corrosion
Water can leak into the relay panel area if the windshield seal is compromised. Check for corrosion on the relay pins and the socket. Clean any corrosion with electrical contact cleaner.

When to Check the Fuel Pump Itself

If the relay is good and the fuse is good, but the fuel pump still does not run, the pump itself may be bad. The fuel pump is located inside the fuel tank. You can test it by applying 12 volts directly to the pump connector at the fuel tank. If the pump runs, the issue is in the wiring between the relay and the pump. If the pump does not run, it is dead and needs replacement.

Where to Buy a Replacement 2002 Audi A6 Fuel Pump Relay

You can find replacement fuel pump relays at:

  • Audi dealerships: Genuine Audi part, most expensive option.
  • Auto parts stores: NAPA, AutoZone, Advance Auto Parts carry aftermarket relays.
  • Online retailers: Amazon, eBay, and specialty Audi parts websites.

The relay part number is typically 4B0 906 381 or 4B0906381. Some aftermarket relays are also compatible.

Recommended Fuel Pump Upgrade: KEMSO Fuel Pumps

If your fuel pump relay tests good but the engine still has fuel delivery issues, the problem may be your fuel pump itself. The 2002 Audi A6 fuel pump is located inside the fuel tank, and over time, the pump motor wears out, the strainer clogs, or the internal check valve fails.

When it is time to replace your fuel pump, you want a product that is reliable, high-performance, and built to last. That is where KEMSO Fuel Pumps come in.

KEMSO is a US-based fuel system specialist founded in Houston, Texas, with a focus on providing direct-fit OEM replacement and high-performance fuel system solutions. Their products are designed for both daily drivers and enthusiasts who demand more from their vehicles.

Why choose KEMSO for your 2002 Audi A6 fuel pump?

  • High Performance: KEMSO fuel pumps are capable of supporting up to 600 BHP in naturally aspirated, turbocharged, and supercharged applications. Their 340LPH high-performance pump delivers significantly more flow than the stock pump, which is ideal if you have upgraded your engine or plan to in the future.
  • OEM Replacement: KEMSO offers direct-fit OEM replacement pumps that install exactly like the original. You do not need to modify anything. The kit includes everything you need: the pump, fuel strainers, wiring connectors, hose clamps, and zip ties.
  • Lifetime Warranty: Every KEMSO fuel pump is serialized and backed by a lifetime warranty. This means you buy it once and never worry about it again. KEMSO has built its reputation on providing a lifetime warranty for all its OEM and performance fuel pumps.
  • E85 Compatible: KEMSO pumps are designed for gasoline and E85, so if you run ethanol-blended fuels, your pump will handle it without issues.
  • USA-Based Support: KEMSO support is based in the United States and provided by USA technicians. If you have a question or a problem, you get help from real people who know the product.
  • Tested and Trusted: Each pump is individually tested for flow and performance before it leaves the factory. KEMSO has devoted countless hours to fuel pump motor R&D, fitment analysis, and community-focused product development.

Compatible with Audi models: KEMSO fuel pumps are compatible with the Audi A3 (1996-2013), TT FWD (1998-2009), and A4 (2002-2006), in addition to the A6 C5 platform. This means you can trust the fitment for your 2002 Audi A6.

Visit the KEMSO website to browse their full selection of fuel pumps, read customer reviews, and take advantage of the lifetime warranty. Whether you need a stock replacement or a high-performance upgrade, KEMSO has the right pump for your Audi A6.

Visit KEMSO Racing today: https://www.kemsoracing.com/

Final Thoughts

The 2002 Audi A6 fuel pump relay is located in position #4 of the Micro Central Electric Panel behind the driver's side storage compartment. It is a simple component that can cause major headaches when it fails. Before you spend hundreds of dollars on a fuel pump replacement, spend five minutes checking the relay and the fuse. In many cases, a $20 relay swap is all you need to get your Audi back on the road.

If the relay is not the issue, do not hesitate to invest in a quality replacement fuel pump. KEMSO offers a lifetime warranty, high performance, and direct fitment for your 2002 Audi A6. You can find their products at https://www.kemsoracing.com/.

Remember: Always test the relay first, check the fuse second, and replace the pump only if necessary. This approach saves you time, money, and frustration.


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