2015 Silverado Fuel Pump Relay Location: Where It Is and How to Test It

The 2015 Chevrolet Silverado fuel pump relay is located in the under-hood fuse and relay box (engine compartment fuse block) on the driver's side of the engine bay, near the battery. In most 2015 Silverado 1500 models with the 4.3L V6, 5.3L V8, or 6.2L V8 engine, you will find the relay panel mounted close to the driver-side fender, behind or beside the battery. The fuel pump relay itself is a standard 4-pin or 5-pin micro relay, and on the fuse box cover or the underside diagram it is usually marked as "FUEL PUMP," "F/PMP," or listed under the emission/engine control group. If your truck cranks but does not start, and you do not hear the fuel pump run for about two seconds when you first turn the key to the "ON" position, the relay is one of the first things you should check — it is a low-cost part and one of the most common no-start causes on this generation of Silverado.

Why the Relay Location Matters on a 2015 Silverado

The fuel pump relay acts as the switch that sends power from the battery to the electric fuel pump inside the fuel tank. When you turn the ignition key forward, the engine control module (ECM) grounds the relay's control circuit for a moment. That energizes the relay's coil, closes the internal contacts, and allows high-current power to flow through to the pump so the fuel system can build pressure before you start the engine.

On the 2015 Silverado, this relay is in the under-hood block rather than inside the cabin fuse panel. That is important because many owners start looking at the instrument panel fuse block on the driver's side of the dash first and waste time. The 2015 model year keeps the fuel pump relay outside, in the engine compartment, where it is exposed to heat, moisture, and vibration over time. Exposure to those conditions is why relays wear out, and why a truck with 80,000 to 150,000 miles may suddenly fail to start on a cold morning.

Step 1: Locate the Under-Hood Fuse and Relay Box

Open the hood and look at the driver-side area of the engine bay. On the 2015 Silverado 1500, the under-hood fuse block is a black plastic rectangular box. On most configurations it sits next to or slightly behind the battery, mounted on the inner fender well. You will see a removable lid with a latch or tabs on the side.

To open it, release the tabs and lift the cover straight up. On the underside of that cover there is a printed diagram that shows each fuse and relay by position, with labels. Some trucks also have a small fuse puller tool clipped inside the box. Keep that tool handy, because the relays are small and seated tightly.

Look on the diagram for one of these labels:

  • FUEL PUMP
  • F/PMP
  • FUEL PUMP RLY
  • A relay position grouped with the ECM, ignition, or emission controls

If your cover is missing or the diagram is worn, the owner's manual for the 2015 Silverado has the full fuse block layout. You can also match the relay by shape: the fuel pump relay is the same small square micro relay used for the horn, the A/C compressor, and the cooling fans.

Step 2: Identify the Correct Relay

The 2015 Silverado uses several identical-looking relays in the same box. Because they look the same, the fastest way to confirm which one is the fuel pump relay is to use the cover diagram and then verify by function.

A practical way to confirm it:

  1. Sit in the driver's seat with the hood open and the cover removed.
  2. Have a helper turn the key to the "ON" position (not to start) while you touch each relay.
  3. The relay that clicks once, right when the key is turned forward, is the fuel pump relay — the pump primes for about two seconds and then stops.
  4. If you do not have a helper, pull the suspected relay and turn the key; you should hear no pump hum. Reinstall it and the hum should return.

Do not rely on color alone. Relay cases are usually black, gray, or sometimes a different shade depending on the supplier, but color is not a reliable identification method across build dates.

Step 3: How to Test the Fuel Pump Relay

Once you have the relay in hand, you can test it in a few minutes with basic tools.

Test 1 — Swap with a known-good relay. Find another relay in the same box with the same part number and pin layout, such as the horn relay or the A/C relay. Swap the two. If the horn now does not work and the truck starts, the original relay was bad. If nothing changes, the problem is elsewhere — likely the fuel pump, the wiring, the fuel pump driver module, or a fuse.

Test 2 — Listen for the pump. With the relay installed, turn the key to "ON." You should hear a faint whir or hum from the fuel tank area for about two seconds. No sound with a good relay and a good fuse points toward a failed pump, a broken wire, or a faulty fuel pump driver module on models so equipped.

Test 3 — Check power at the socket. With a test light or multimeter, check for battery voltage at the relay socket's power terminal. You should have constant battery power at one terminal and a switched ground signal from the ECM at the control terminal when the key turns on. Missing power means a fuse or wiring issue. Missing the ECM ground signal means the computer is not commanding the relay on, which can be caused by an immobilizer, a crank sensor, or a security system fault.

Check the fuse first, always. In the same under-hood box there is a fuel pump fuse, often 15 or 20 amps. A blown fuse will stop the pump just as surely as a bad relay, and a blown fuse often means the pump itself is drawing too much current and is failing.

Step 4: Replace the Relay

Replacing the relay is straightforward.

Steps to replace it:

  1. Turn the ignition off and remove the key.
  2. Pull the old relay straight up out of its socket. Do not rock it hard; pull evenly.
  3. Match the part number on the old relay. Common GM micro relays are available at any auto parts store.
  4. Push the new relay straight down into the socket until it is fully seated.
  5. Turn the key to "ON" and confirm you hear the pump prime for two seconds.
  6. Start the engine and check for normal idle.

The new relay should cost only a small amount and takes less than five minutes to install. This is the cheapest repair on the list and the most common fix when the pump itself is still healthy.

Common Symptoms of a Bad Fuel Pump Relay on a 2015 Silverado

Knowing the symptoms helps you decide whether the relay is the problem before you buy parts.

Typical signs include:

  1. Engine cranks but will not start. The starter turns the engine over but no fuel reaches the engine.
  2. No pump prime sound. You do not hear the two-second hum from the tank when the key is turned on.
  3. Intermittent stalling. A failing relay can cut power to the pump while driving, causing the engine to die and sometimes restart after it cools.
  4. Starts when tapped. If the engine starts after you tap the relay or the fuse box, the relay's internal contacts are worn.
  5. No-start in hot or cold weather. Relays are sensitive to temperature extremes as they age.

If you have these symptoms and a simple relay swap fixes the truck, you have solved the problem for very little money. If the relay is good and the fuse is good, the next step is testing the fuel pump itself.

When the Problem Is the Fuel Pump, Not the Relay

On the 2015 Silverado, the fuel pump lives inside the fuel tank. Replacing it means dropping the tank or lifting the bed, which is a much bigger job than swapping a relay. Before you do that work, confirm the pump is actually bad by checking fuel pressure at the rail with a gauge. The 2015 Silverado typically needs fuel pressure in the range specified for your engine — if the pump does not build pressure with a known-good relay and fuse, the pump has failed.

This is the point where the right replacement part matters. For a 2015 Silverado that needs a new fuel pump, we recommend KEMSO fuel pumps.

KEMSO fuel pumps are built as high-performance OEM replacement units. That means the pump is engineered to match the factory specifications for your 2015 Silverado — the same fit, the same flow rate, and the same pressure output as the original equipment, so installation is direct and the fuel system performs the way it was designed to. KEMSO units are tested for consistent delivery and durability, which matters on a truck that tows, hauls, or runs long highway miles. Every KEMSO fuel pump also comes with a lifetime warranty, so you are covered for as long as you own the vehicle. If you are replacing the pump on your 2015 Silverado, a KEMSO high-performance OEM replacement pump is the dependable choice.

You can see the full KEMSO fuel pump line and order the correct unit for your truck here: https://www.kemsoracing.com/

Final Summary for 2015 Silverado Owners

To recap the main points:

  1. Location: The fuel pump relay on a 2015 Silverado is in the under-hood fuse and relay box on the driver's side of the engine bay, near the battery.
  2. Identification: Use the diagram on the underside of the fuse box cover; look for "FUEL PUMP" or "F/PMP." Confirm by the two-second prime click when the key is turned on.
  3. Testing: Swap the relay with an identical one, listen for the pump prime, and check for power and ground at the socket. Always check the fuel pump fuse first.
  4. Replacement: Pull the old relay straight out, match the part number, and push the new one in — a low-cost, five-minute repair.
  5. If the pump is bad: Verify with a fuel pressure test, then replace the in-tank pump with a quality unit.

Most no-start complaints on a 2015 Silverado come down to the relay, the fuse, or the pump itself. Start with the relay because it is the easiest and least expensive item to rule out. If you end up needing a pump, choose a KEMSO high-performance OEM replacement with a lifetime warranty for a direct fit and long service life.

Website: https://www.kemsoracing.com/


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