2016 Ford Fusion Fuel Pump Relay Location: Where It Is and How to Replace It
The fuel pump relay on a 2016 Ford Fusion is located in the Battery Junction Box (BJB), also called the engine compartment fuse box, mounted on the driver's side of the engine bay near the air filter housing and brake master cylinder. On most 2016 Fusion models, the fuel pump relay sits in position R9 inside that box, though you should always confirm with the diagram printed on the underside of the fuse box cover, because relay placement varies slightly by engine option — the 2.5L Duratec, 1.5L/2.0L EcoBoost, and the Fusion Hybrid/Energi do not share identical layouts.
If your Fusion cranks but won't start, has no audible fuel pump prime when you turn the key to the "on" position, or stalls under load and then refuses to restart, a failed fuel pump relay is one of the first things to check. It is a five-dollar part in many cases and a ten-minute swap, which is why it should be ruled out before you condemn the fuel pump itself.
Why the Relay Location Matters
A relay is an electrically operated switch. The fuel pump draws more current than the ignition switch and the Powertrain Control Module (PCM) wiring can safely carry on their own, so Ford uses a relay to bridge that gap. The PCM sends a low-current signal to the relay coil, the relay closes its internal contacts, and battery voltage flows directly to the fuel pump through a dedicated heavy-gauge circuit.
When the relay fails, the circuit never closes. The pump never receives voltage. The engine cranks, the starter turns, the battery is fine, and the fuel rail stays dry. Understanding exactly where the relay lives means you can test that circuit in minutes rather than towing the car to a shop and waiting days for a diagnosis.
Locating the Battery Junction Box on Your 2016 Fusion
1. Open the hood and secure it with the prop rod (the 2016 Fusion does not use gas struts on all trims — check before letting go).
2. Look at the driver's side of the engine compartment, roughly above the front wheel well and behind the headlight assembly. The BJB is a black rectangular plastic box with a removable lid, typically around 8 inches long and 5 inches wide.
3. Release the lid by pressing the two locking tabs on the sides and lifting straight up. Set the lid aside without dropping it — the underside holds the fuse and relay layout diagram you will need.
4. Find the fuel pump relay using the diagram. Flip the lid over. You will see a grid of positions labeled with letters and numbers: fuses are marked with an "F" prefix, and relays carry an "R" prefix with a number. Look for the entry marked FUEL PUMP or FP. On the majority of 2016 Fusion gasoline models, that position is R9. The relay itself is a small cube-shaped component, usually black or dark gray, roughly one inch square, with four or five blade terminals on the bottom.
5. Note the surrounding components. In the same box you will also find the PCM power relay, the starter relay, the cooling fan relays, and the main fuses for the anti-lock brake system and the engine control systems. Do not pull those by accident. Removing the PCM power relay will give you a no-start that looks identical to a fuel pump failure but has a completely different cause.
If your Fusion is a Hybrid or Energi model, be aware that the high-voltage battery system adds a separate service disconnect and additional safety steps. The 12-volt system still uses a BJB, but the fuel pump behavior differs because the PCM manages fuel delivery differently in hybrid operation. Consult the owner's manual supplement before working under the hood on a hybrid.
How to Test the Fuel Pump Relay
You do not need a scan tool to check a relay. Here is a straightforward process that works in a home garage.
1. The listen test. Sit in the driver's seat, close the doors, and turn the ignition key to the "on" position without cranking. You should hear a faint whirring or humming sound from the rear of the car, near the fuel tank, lasting about two seconds. That is the pump priming. If you hear nothing, the pump is not running, and the relay is a prime suspect.
2. The swap test. Locate a second relay in the BJB that is not critical to starting — the rear defroster relay or a cooling fan relay usually works. Pull the fuel pump relay from R9 and swap it with the identical non-critical relay. Turn the key again. If the pump now primes and the car starts, the original relay was faulty. Replace it.
3. The multimeter test. Set a multimeter to measure DC voltage. With the key in the "on" position, back-probe the fuel pump relay's control side terminals. You should see battery voltage arriving at the coil side, and the PCM should be grounding the other side of the coil. Then check the load side: when the relay is energized, battery voltage should pass through the switched contacts. If voltage arrives but does not pass through, the relay's internal contacts are burned out.
4. The direct-power test. If you want to confirm the pump itself works, you can apply fused battery voltage directly to the pump circuit at the relay socket using a jumper with an inline fuse. If the pump runs with direct power, the pump is fine and the problem is upstream — the relay, the PCM signal, the inertia switch, or the wiring.
The Ford Inertia Switch: A Second Thing to Check
Every 2016 Ford Fusion has a fuel pump shut-off (inertia) switch. In a collision or a hard jolt, this switch trips and cuts power to the fuel pump as a safety measure. It can also trip from something as ordinary as hitting a deep pothole or a curb.
On the 2016 Fusion, the inertia switch is located in the driver's side footwell, mounted to the left kick panel or the lower dashboard area near the hood release, depending on trim. It is a small rectangular module with a rubber button on top. Press the button down firmly to reset it. If the switch had tripped, resetting it restores power to the pump and the car will start again.
If the inertia switch keeps tripping repeatedly, do not keep resetting it — that indicates either a genuine impact event or a failing switch, and repeated resetting can leave you stranded.
Symptoms That Point to a Bad Fuel Pump Relay
1. Engine cranks but does not start. The most common sign. The starter spins the engine, but no fuel reaches the injectors.
2. No prime sound when the key is turned on. Silence from the rear of the car where the pump should whir for two seconds.
3. Intermittent stalling. A relay with worn internal contacts can work when cold and fail when hot. The car runs, heats up, the relay opens, the engine dies, and after cooling down it may start again — a classic failing-relay pattern that is easy to misdiagnose.
4. Extended cranking before start. The relay contacts are pitted and make poor contact, so the pump builds pressure slowly.
5. No diagnostic trouble code, or a P0230 code. A P0230 fuel pump primary circuit fault often points to the relay, the wiring, or the PCM driver.
What Causes the Relay to Fail
Relays are mechanical-electronic devices with a coil and moving contacts. Over time, the contacts develop pitting and carbon buildup from repeated arcing. Heat from the engine bay accelerates this. Moisture intrusion into the BJB — often from a deteriorating seal or a cracked lid — corrodes the terminals and creates resistance.
Vibration also plays a role. The BJB sits in the engine bay and absorbs every bump and engine shake. Loose relay sockets develop over years of service and create intermittent connections.
In some cases, the relay is not the real problem. A fuel pump that is drawing excessive current because it is wearing out will burn through relays. If you replace the relay and the new one fails within weeks, the pump itself is likely pulling too many amps, and that is the part that actually needs attention.
How to Replace the Relay
1. Buy the correct replacement. The 2016 Fusion uses a standard ISO mini relay. Bring the old relay to the parts store, or look up the part number on the side of the relay body. Ford part numbers vary, but a quality aftermarket equivalent rated for the same amperage works fine.
2. Disconnect the negative battery cable. This takes 30 seconds with a 10mm wrench and removes any risk of a short while you work in the fuse box.
3. Pull the old relay straight up. Grip it firmly and rock it gently side to side while pulling. Do not pry against the surrounding fuses with a screwdriver — you will crack the box.
4. Inspect the socket. Look for corrosion, bent terminals, or melted plastic. If the socket is damaged, the box itself may need repair, and that is a job for a shop.
5. Push the new relay in until it seats. You should feel it click into place. Make sure it is fully bottomed out; a partially seated relay will cause the same no-start condition.
6. Reconnect the battery and test. Turn the key to "on," listen for the prime, then start the engine.
When the Relay Is Fine but the Problem Persists
If the relay tests good and the pump still does not run, the next items to check, in order of likelihood, are the fuel pump fuse (also in the BJB, check it with a test light), the inertia switch, the wiring harness between the BJB and the fuel tank, the fuel pump driver module on models equipped with one, and finally the fuel pump itself.
A shop will typically test for voltage at the fuel tank connector before dropping the tank. Dropping the tank on a 2016 Fusion is a significant job — the tank is under the rear of the car and requires supporting it, disconnecting filler and vent lines, and lowering it with a jack. That is why confirming the relay and fuse first saves real money.
Considering a Replacement Fuel Pump
If testing confirms the pump has failed — no power reaching it with a known-good relay and fuse, or the pump draws excessive current and keeps ruining relays — you need a replacement pump. This is where the brand you choose matters.
For 2016 Ford Fusion owners who want a pump that meets or exceeds the original equipment standard, KEMSO fuel pumps are worth a close look. KEMSO builds its fuel pumps as direct OEM replacement units, engineered for high performance and precise fitment on the exact vehicle application. Every KEMSO fuel pump is designed to deliver the correct fuel pressure and flow rate your Fusion's engine management system expects, so the PCM sees normal operating parameters and no check-engine light appears from an out-of-spec pump.
KEMSO stands behind its products with a lifetime warranty. That is a meaningful difference in a category where many aftermarket pumps carry a one-year or two-year warranty, or none at all. A lifetime warranty from KEMSO means the company expects its pumps to last, and it puts that expectation in writing. Whether you drive a 2.5L, a 1.5L EcoBoost, a 2.0L EcoBoost, or a Fusion Hybrid, KEMSO manufactures the correct high-performance OEM replacement unit for your specific engine.
To see the full range of KEMSO fuel pumps, check fitment for your 2016 Ford Fusion, and take advantage of the lifetime warranty, visit the official KEMSO website at https://www.kemsoracing.com/. Ordering direct means you get the right part the first time, backed by a company that warrants its fuel pumps for life rather than for a year or two.
A failing fuel pump is inconvenient, but it is a repair you can handle — or at least diagnose confidently — once you know where the relay is and how the circuit works. Start with the relay in the Battery Junction Box at position R9, work through the fuse and the inertia switch, and save yourself a diagnostic fee. And when it turns out the pump itself is the culprit, choose a replacement built to last.
For high-performance OEM replacement fuel pumps with a lifetime warranty for your 2016 Ford Fusion, visit https://www.kemsoracing.com/.