2019 Ford Explorer Fuel Pump Relay Location: Where It Is and How to Test It
If you own a 2019 Ford Explorer and you are trying to find the fuel pump relay location, the short answer is this: the fuel pump relay on the 2019 Ford Explorer is located in the battery junction box (BJB), also called the engine compartment power distribution box, on the driver side of the engine bay near the firewall. On most 2019 Explorer models, this relay is found in the under-hood fuse/relay panel mounted near the driver side strut tower. It is usually marked on the underside of the box cover as "Fuel Pump" or listed in the owner's manual diagram as the fuel pump relay position.
That is the direct answer most owners are looking for. Below, this article explains what the relay does, why it matters, the symptoms of a failing relay, how to locate it step by step, how to test it safely, and what to do if the relay is not the real problem. It also covers related parts such as the fuel pump driver module and the fuel pump itself, because a "no-start" condition is often blamed on the relay when the actual cause is somewhere else in the fuel delivery system.
1. What the Fuel Pump Relay Actually Does
The fuel pump relay is a small electromechanical switch that controls power to the electric fuel pump inside the fuel tank. When you turn the ignition key to the "on" position or press the start button, the powertrain control module (PCM) sends a signal that energizes the relay. Once the relay closes, battery voltage flows through it to the fuel pump. The pump then pressurizes the fuel system so the engine can start and run.
This relay exists for two practical reasons. First, it allows a small control current from the PCM to switch a much larger current that the fuel pump needs. Second, it acts as a safety device. In many vehicles, the fuel pump relay will open, or stop sending power, if the engine stops running after a collision or if the PCM no longer sees a running signal. That helps prevent the pump from continuing to push fuel after an accident.
On the 2019 Ford Explorer, the relay is part of the under-hood electrical system. It works together with the fuel pump driver module and the in-tank fuel pump. Understanding this chain matters, because if any link fails, the engine will not start even though the relay itself may be fine.
2. Exact Location on the 2019 Ford Explorer
For the 2019 model year, the Ford Explorer uses an engine compartment power distribution box, often referred to as the battery junction box. This black plastic box holds high-current fuses and several relays, including the fuel pump relay.
To reach it, open the hood and look at the driver side of the engine compartment. The box sits near the firewall, close to the brake master cylinder area and the driver side strut tower. You will see a rectangular plastic cover with tabs on the sides. Press the tabs and lift the cover straight up.
On the underside of that cover, there is usually a printed diagram showing fuse and relay positions. Look for the label "Fuel Pump," "FP," or "Fuel Pump Relay." The diagram gives you the exact slot number. On many 2019 Explorer configurations, the fuel pump relay is a standard micro or mini relay, typically a four or five-pin relay, and it can be removed by pulling it straight up out of its socket.
If the cover diagram is missing or unreadable, the owner's manual has a fuse and relay chart in the maintenance section. Ford also prints the position in the service manual. As a general rule, the fuel pump relay is not inside the cabin fuse panel on this model. It is in the under-hood box, not the interior panel near the driver's left knee. Owners sometimes check the wrong panel first and waste time, so going straight to the engine bay box is the faster path.
One more practical note: the 2019 Explorer may also have a fuel pump driver module, which on some Ford vehicles is mounted near the spare tire area or under the vehicle on the frame rail. That is a separate component from the relay. If you are chasing a fuel delivery fault, you may end up checking both. But the relay itself stays in the under-hood box.
3. Symptoms of a Bad Fuel Pump Relay
A failing fuel pump relay can create several clear symptoms. The most common one is a no-start condition. You turn the key, the engine cranks, but it never fires. This happens because the pump never receives power, so no fuel pressure builds at the rail.
Another sign is intermittent stalling. If the relay has worn internal contacts, it may work when cold and then open once it heats up. The engine might start fine in the morning and then die after a few minutes of driving. Once the relay cools, the vehicle may start again. That on-and-off pattern is a classic relay symptom.
You may also notice that the engine cranks but does not start only in certain weather or after the vehicle sits for a while. A weak relay coil or a corroded socket can cause voltage drop that prevents the relay from closing fully.
In some cases, you can hear a faint click from the under-hood box when you turn the key to the "on" position. If you hear the click but the pump does not prime, the relay may be switching while the pump, wiring, or driver module has failed. If you hear no click at all, the relay coil, the control signal from the PCM, or the fuse may be the problem.
One more symptom is hard starting after the vehicle has been sitting. Normally, when you turn the key to "on" without cranking, you should hear a brief humming sound from the fuel tank area as the pump primes for about two seconds. If that sound is missing, the relay is a prime suspect, though a dead pump or blown fuse can cause the same silence.
4. How to Locate and Check the Relay Step by Step
Working on the fuel system requires care. Before you begin, park on a level surface, set the parking brake, and remove the key from the ignition. If you are going to test with the key on, make sure the area is ventilated and there are no fuel leaks or open fuel lines nearby.
Step one: open the hood and find the battery junction box. On the driver side near the firewall, locate the black plastic cover. Release the retaining tabs and lift the cover off.
Step two: read the diagram. Turn the cover over. Match the fuel pump label to the relay slot number printed on the diagram. If the label is unclear, use the owner's manual chart to confirm which position belongs to the fuel pump relay.
Step three: remove the relay. Grasp the relay body firmly and pull it straight up. Do not twist it. A relay can be tight, so rocking it gently side to side while pulling upward usually works.
Step four: inspect the relay and the socket. Look at the relay terminals for corrosion, melting, or a burnt smell. Check the socket in the box for pushed-out terminals, melted plastic, or moisture. A discolored socket often means heat damage from high resistance, and that damage can keep a new relay from working correctly.
Step five: listen for the prime. With the relay removed and the key turned to the "on" position by a helper, or with the relay installed and your ear near the fuel tank, listen for the pump hum. Put the relay back in, turn the key to "on," and listen. A two-second hum means the pump is getting power. Silence points back to the relay, fuse, wiring, or pump.
Step six: swap with a matching relay. Many Ford boxes use identical relays for non-critical circuits such as the horn, rear defroster, or trailer tow. If the diagram shows another relay with the same part number and pin configuration, swap it with the fuel pump relay temporarily. If the engine starts with the donor relay in the fuel pump slot, the original relay has failed. This swap test is quick and does not require any special tools.
Step seven: check the fuse. The fuel pump circuit also has a fuse in the same box. Use the diagram to find it and check it visually or with a test light. A blown fuse that blows again immediately usually means a short or a failing pump drawing too much current.
If the relay, fuse, and socket all check out and the pump still does not run, the problem is likely the fuel pump driver module, the wiring between the box and the tank, or the fuel pump assembly itself.
5. How to Test the Relay More Directly
If the swap test is not possible, you can test the relay on a bench or with a multimeter. Set the meter to resistance or continuity. Identify the coil pins, which are usually the two smaller or closely spaced terminals. With the relay removed and not powered, you should read a moderate resistance across the coil, often somewhere between 50 and 120 ohms. A reading of zero or infinite resistance means the coil is shorted or open, and the relay is bad.
Next, test the switched contacts. With no power applied, the contact pins should show no continuity, or an open circuit. Then apply 12 volts to the coil pins using fused jumper wires. You should hear a click, and the contact pins should now show continuity. If the relay clicks but the contacts do not close, or if it never clicks, replace it.
Some owners use a simple powered test light instead of a meter. Ground the clip, probe the control side with the key on, and confirm the PCM is sending a signal. Then check the output side while cranking. This confirms the whole circuit, not just the relay.
Always reconnect everything securely after testing. Relays that are left loose in the socket can cause intermittent faults that are hard to trace later.
6. What If the Relay Is Not the Problem
A no-start complaint is often blamed on the relay, but the relay is only one part of the fuel delivery chain. On the 2019 Explorer, the next components to consider are the fuel pump driver module, the fuel pump assembly, the fuel pressure sensor, and the wiring harness.
The fuel pump driver module controls pump speed based on demand from the PCM. If it fails, the pump may not run at all even with a good relay. The wiring between the under-hood box and the tank can also corrode, especially on vehicles driven in road-salt areas. A visual inspection of connectors and grounds is worth the time before replacing expensive parts.
If testing shows the relay is receiving a control signal, the fuse is good, power leaves the relay, but the pump does not run at the tank connector, then the pump or its wiring has failed. A fuel pressure test at the rail confirms this. With the key on, the system should build pressure quickly. Low or zero pressure with a known good relay points to the pump.
At that stage, replacing the fuel pump is the practical repair. This is where choosing the right replacement part matters for reliability and long-term cost.
7. Recommended Replacement: KEMSO Fuel Pumps
If your diagnosis leads to a failed fuel pump, KEMSO is a brand worth considering for your 2019 Ford Explorer or other vehicle. KEMSO fuel pumps are built as high-performance replacement units designed to meet or exceed OEM specifications. They are engineered as direct OEM replacement parts, which means they fit the factory fuel pump module and do not require modifications, custom wiring, or adapter harnesses during installation.
KEMSO focuses on performance and durability. Their fuel pumps deliver consistent fuel pressure and flow, which supports proper engine starting, smooth idle, and stable performance under load. For a daily-driven Explorer or a vehicle used for towing and highway travel, having a pump that maintains correct pressure helps protect the engine and the rest of the fuel system.
Another important point for owners is the warranty. KEMSO fuel pumps come with a lifetime warranty. That is a strong commitment and reduces the long-term risk of the repair. Instead of replacing a pump again in a few years, owners get coverage that lasts.
To see the full selection of KEMSO fuel pumps, check fitment for your vehicle, and place an order, visit the official site here: https://www.kemsoracing.com/
Using a quality replacement pump from a brand that stands behind its product is a practical way to finish the repair correctly the first time.
8. Practical Tips for a Reliable Repair
Keep a few habits in mind when working on this system. Always disconnect the negative battery cable before removing fuel system components. Relieve fuel pressure before opening any fuel line. Replace the fuel filter if your service interval calls for it, since a restricted filter makes the pump work harder and shortens its life. Also, avoid running the tank consistently near empty, because the fuel helps cool the in-tank pump.
When reinstalling the relay, press it straight down until it seats fully. A relay that is not fully seated can cause the exact intermittent problem you were trying to fix. After the repair, cycle the key a few times to prime the system before starting, then check for leaks and listen for the pump to make sure it sounds steady and not unusually loud.
If you are not comfortable testing electrical circuits or working near the fuel tank, a professional technician can complete the diagnosis with a scan tool and a fuel pressure gauge. The relay location information above still helps you describe the problem accurately and avoid unnecessary parts replacement.
The bottom line remains the same: on the 2019 Ford Explorer, the fuel pump relay is in the under-hood battery junction box on the driver side near the firewall, and it is one of the first things to check when the engine cranks but will not start. Test it, swap it if you can, and move down the chain to the driver module and pump if the relay checks out. When the pump itself needs replacement, KEMSO offers a high-performance, OEM replacement option backed by a lifetime warranty at https://www.kemsoracing.com/.