What to do if your fuel pump relay stops working?

Connect one lead to one of the power circuit pins, and connect the other lead to the other power terminal. If you hear a beeping sound, your fuel pump relay’s power pins have shorted. Replace the relay. You can test the fuel pump relay, along with many other parts in your car, with the cheap and handy multimeter. (Photo Source: carcody)

Where does the electricity from the fuel pump relay come from?

This is the ground from the electromagnetic coil inside the relay that receives electricity from a switched power source to pin #86.

Where is the fuel pump fuse box located?

The engine’s or the dashboard fuse box is usually a long black box containing a fuel pump relay and various other fuses and relays. For different vehicles, the fuel pump relays can be located in different places.

What happens when a fuel pump goes bad?

The engine turns off if the combustion chamber’s fuel is inadequate or doesn’t have the proper pressure. The part that ensures none of this happens is the fuel pump, and it cannot work perfectly if the fuel pump relay develops any issues. A faulty fuel pump relay can also cause the engine not to start at all and be completely dead.

Where do you find the fuel pump relay?

When you shut off the ignition, it powers down the fuel pump. In most vehicles, the fuel pump relay can often be found in the fuse box in the engine bay, which is usually a long black box which contains fuel pump relay along with various other fuses and relays.

Why is my fuel pump relay not working?

Most of the time, if I leave the key in the On position, after several seconds to a few minutes, it will all of the sudden prime and the gauge comes alive. Then it will work for a few days until the next time it randomly doesn’t. I have ruled out the Passkey issue. The fuel pump relay works as it should. I always have power to Pin 30.

Is there an ECM signal to the fuel pump relay?

The fuel pump relay works as it should. I always have power to Pin 30. I believe the ECM tells the relay to work via the green/black wire to Pin 85. This should happen for 2 seconds when the key is turned on. I have tested this when the issue is occurring and have confirmed that no signal is being sent from the ECM.

Is there a way to make a fuel pump run?

I can make the pump run by using a jumper at the relay and by utilizing the Prime test slot; however, even when the pump is running continuously via the jumper, the truck will not start – just cranks. I’ve tested every fuse I have inside the cab and under the hood. I’ve checked grounds.

How much does it cost to replace a fuel pump relay?

You can easily find fuel pump relays online or at any automotive spare parts shop.The average replacement cost of the fuel pump relay ranges from $90 to $150, of which $20-$50 is for parts and the remaining is the labour cost.

What are the symptoms of a bad fuel pump?

The engine may still crank when the key is turned, however it will not be able to start due to lack of fuel. This symptom can also be caused by a wide variety of other issues, so having the vehicle properly diagnosed is highly recommended. 3. No noise from the fuel pump

Where is the fuel pump control module located?

It is often found in the fuse box located in the engine bay and functions as the primary electronic switch that controls power to the fuel pump. The fuel pump relay is usually controlled by the ignition or Powertrain Control Module, and when switched on, will provide current to the fuel pump so that it may function.

Is there a fuse for the fuel pump?

Click to expand… or maybe the fuse box is shared with differently optioned trucks and that is the spot for a fuel pump relay on a diesel :shrug: My friend has a 07.5 chevy with a fuse and relay but in my 09 it doesn’t.

Is there a relay for the fuel pump?

I’m guessing there is a relay because every fuse that has to do with the fuel pump is missing. Not even a dealership could help me with an answer. Im just being curious and figured The wonderful GMFS could help me out. You tell me? I’m guessing there is a relay because every fuse that has to do with the fuel pump is missing.

Is there a fuse and relay on a GMC Truck?

My friend has a 07.5 chevy with a fuse and relay but in my 09 it doesn’t. My truck kept dying on me and throwing codes. Ended up being the module above the spare tire not being sealed correctly from gm. Definitely was confused tho when I didn’t see a relay or fuse…

Is there a way to disable the fuel pump?

If it turns out that pulling the FSCM isn’t the way to disable the fuel pump, then I’ll make another attempt at running the cleaner through the schrader valve on the fuel rail. Thanks again for all your assistance. You did replace the #21 control module before attempting to start the vehicle didn’t you?

Is there no power to the fuel pump?

No power to the fuel pump and the fuel relay is not getti… Q: No power to the fuel pump and the fuel relay is not getting power. My car has 190000 miles.

This is the ground from the electromagnetic coil inside the relay that receives electricity from a switched power source to pin #86.

No power to the fuel pump and the fuel relay is not getti… Q: No power to the fuel pump and the fuel relay is not getting power. My car has 190000 miles.

How can I Fix my Chevy fuel pump?

Ask a Chevy Mechanic for Answers ASAP By continuing to use this site you consent to the use of cookies on your device as described in our cookie policy unless you have disabled them. My Chevy has no power to fuel pump. How can I fix it? no power to fuel pump… Submitted: 10 years ago. Category: Chevy

Where is the power wire on a Chevy fuel pump?

Want to make sure its a 5.7L engine with the classic style truck and not the new style truck with the 6.0L Right? On the fuel pump connector, the gray wire is the power wire. The thick black wire is the ground.

How can I tell if my fuel pump has no power?

There should be 3 power terminals. The relay only runs for 2 seconds after you turn the key on. So you have just a little time to test it. That will tell if you have power going from the relay and then the issue is down stream from the relay. You can also check it at that connector. Was this answer helpful?

Why does the fuel pump relay need to be Tip Top?

The fuel pump relay needs to function in tip-top condition if the engine is expected to run without any issues. Therefore, any compromise in the fuel pump relay can directly cause engine problems, such as the stalling of the engine.

How many pins does a fuel pump relay have?

The fuel pump relay does often have 4 pins, and in this case, it is often easy. If your relay has more pins and not the same numbers mentioned here, you need to check a wiring diagram. Lift it and check under it for the numbers 30, 85, 86, and 87. If you locate these numbers, you can put the fuel pump relay back.

Is the fuel pump relay controlled by the PCM?

Consequently, the fuel pump relay is usually controlled by, the ignition or powertrain control module (PCM). As a result, when switched on, the fuel pump relay; will provide current to the fuel pump, so that it may function. Therefore, any faults with it, can cause fuel pump issues.

Which is the secondary side of the fuel pump relay?

Terminals 87 and 30 are the secondary side of the relay. Consequently, It acts as the “switch” that connects electrical current, from one terminal to the other. Use Jumper wires to supply 12v power to terminals 86 and 85. Next, use a test light on terminals 87 and 30, to see if you have power.

What happens when a fuel pump relay goes bad?

If the fuel pump relay has an issue while the vehicle is operating it will cut off power to the fuel pump, which will cause the engine to stall. A faulty relay may allow the vehicle to be restarted a short while later, while a completely failed relay will not.

Is there a fuel pump relay on a Silverado?

My plan to clean the fuel injectors on my 2008 Silverado LS 4.8L V8 came to an abrupt halt when I was unable to disable the fuel pump relay because it is missing from the spot where it should be located according to the schematic in the owner’s manual. Does anyone have any ideas on this?

What happens when you remove the fuel pump key?

When the key is removed from the vehicle, the fuel pump will continue to run. In this article & video the diagnosis and repair of the faulty internal fuel pump relay will be covered. If playback doesn’t begin shortly, try restarting your device.

Where is the fuel pump in a car?

The fuel pump is located in the fuel tank, near the rear of the vehicle and can usually be heard when the engine starts. A healthy fuel pump plus a healthy fuel pump relay will often produce a variation of a low volume hum or whine which can be heard from inside the vehicle, or from the outside, near the fuel tank.

What does a bad fuel pump relay do?

A bad fuel pump relay will cut the power to your car and stall the engine while you are driving. Keep in mind that a bad fuel pump relay might be faulty or in total failure. In either example, the engine might stall. A relay that is faulty might allow you to restart your engine after you give it a break.

What are the symptoms of a bad fuel pump fuse?

Unusual noises, sputtering or backfiring may also be indicative of a bad fuel pump. If the flow to the fuel injection system in the vehicle is not consistent, the engine may develop problems. Watch for things like a hesitant start or take-off, or a problem with starting the vehicle.

Why is my fuel pump not working?

Too much fuel into the fuel injectors can cause them to break down and fail, while too little of it can lead to the fuel pump not turning on. In order to maintain a proper mixture of air and fuel, a proper pressure of fuel is required, which is balanced with the help of a fuel pressure regulator.

Is there a relay switch for the fuel pump?

In addition to controlling the flow of fuel to the engine, the relay also keeps the electric fuel pump from functioning after a collision, minimizing the chance of fire igniting after an accident. After a collision, the fuel pump relay switch is automatically activated, preventing the vehicle from cranking.

What happens if the fuel pump does not work?

Without a working relay, the pump cannot inject the necessary fuel to complete the ignition process. Note that you may still hear the engine making noise when you try to start your vehicle even if the relay does not work. Other parts of your car’s engine might be in working order, but they won’t have fuel. 2. The Engine Starts and Stalls

What are the symptoms of a fuel pump relay problem?

1. Engine stalls One of the first symptoms of an issue with the fuel pump relay is an engine that suddenly stalls. If the fuel pump relay has an issue while the vehicle is operating it will cut off power to the fuel pump, which will cause the engine to stall.

Fuel pump relay Replacement cost. The average replacement cost of the fuel pump relay is around $90 and $150. The parts may cost you between $20 and $50, while the remaining cost is the labour cost. Fuel pump relay is a small electronic device which is easily acquired online or at the nearest spare parts shop.

What are the symptoms of a bad fuel pump relay?

A bad fuel pump relay can cause many different symptoms. Here are the most common ones The fuel pump relay is an important component of the fuel system of your vehicle. The fuel pump relay gives the fuel pump power when it is time to build up fuel pressure in the rail.

How do you clean a fuel pump relay?

Since any debris will affect the fuel pump relay’s performance, you should regularly inspect and clean it when necessary. The fuel pump relay is an electrical car part, thus be extremely careful when handling a relay. First, take off the relay and use the blower to blow off dirt and dust for about 1-2 minutes.

What should I do if my fuel pump is not working?

Usually, when you start your car the fuel pump gives off a slight buzzing sound signaling that it has started working. However, if there is any problem with the fuel pump relay the fuel pump will not respond at all and you will be left turning the ignition key again and again. If you experience such an ordeal, it is time to visit the mechanic.

Can a bad fuel pump shut off switch cause no start?

A no start condition can also be caused by a wide variety of other issues, so having the vehicle diagnosed is highly recommended. While many fuel pump shut off switches will usually last the life of the vehicle, they can sometimes fail and cause problems with the drivability of the vehicle.

What happens to the fuel pump when the engine dies?

Ride it just a block or so and it dies. (engine dies but all lights etc are still on) When I switch the button to run I hear the fuel pump relay chatter and the fuel pump itself tries to whine, but never completes the full “whine cycle”. Eventually after repeated tries on the run switch the relay stops chattering completely and I get nothing.

Why does my fuel pump whine when I Turn on the engine?

I turn the ignition and hear the pump whine. Hit the start button and it fires up. Ride it just a block or so and it dies. (engine dies but all lights etc are still on) When I switch the button to run I hear the fuel pump relay chatter and the fuel pump itself tries to whine, but never completes the full “whine cycle”.

What causes a fuel pump to stop working?

However, this can happen due to several other reasons, such as a choked fuel filter, so you should always properly diagnose your car before replacing any parts. If the fuel pump relay may have any bad solderings inside it, it might suddenly lose the relay connection and stop delivering power to the fuel pump.

When is the fuel pump relay turned on?

The fuel pump relay is an important component of the fuel system of your vehicle. The fuel pump relay gives the fuel pump power when it is time to build up fuel pressure in the rail. Whenever you turn on the ignition of your vehicle, the fuel pump relay is turned on. There are different reasons due to which the fuel pump relay fails.

Where to check for no start fuel pump?

The first thing you want to do is check the fuse panel to see if the fuse is blown. If your car has two fuse panels than the one in the engine compartment; should be the correct one to check. The fuse panel or circuit box is usually located near the battery; and is a small black box with a removable lid.

Where is the fuel pump relay on a Pontiac Grand Am?

The fuel pump relay is #18 in the fuse box. Start with the car off, and have somebody else put the key in the cars ignition and attempt to start the car while you listen to the relay. If you can hear this relay make a “clicking” noise as the car attempts to start, then it is working properly.

How can I reset the fuel cut off?

This is similar to an electrical circuit breaker in your home which can be easily reset by pushing the button or pulling the leverage down. All modern fuel injection cars are equipped with an inertial fuel cut off switch that shuts off the power supply for the fuel pump if the vehicle is in a collision.

How do I reset the fuel pump shut off switch?

Push the button on the inertial switch; it should be clearly marked as the fuel pump reset, and may be in a contrasting color to the case. You may need to turn the ignition key to the on or accessory position to energize the module and reset the switch. Proceed to the next step if your inertia switch doesn’t use an external button.

The fuel pump relay is activated whenever the ignition is turned on. A fuel pump relay functions primarily to maintain a consistent voltage supply to the fuel pump. The ignition or powertrain control module (PCM) usually controls the fuel pump relay.

What kind of circuit does a fuel pump relay have?

Well, every Ford fuel pump relay has two basic circuits and for the purpose of our discussion, we’ll call them: A high current circuit. A low current circuit. Both of these are completely independent from one another, in other words, voltage/current flowing thru’ these circuits don’t mix.

Why does my Ford pickup have a green relay?

You’ll be able to find out if the fuel pump relay, or the fuel pump Inertia Switch, or the fuel pump is the cause of the No Start Condition on your Ford car or pickup. If your fuel injected Ford pickup, van, or car still has the Ford relay, this bad boy will be a green color (like the one in the image viewer).

Where is the fuel pump and relay wire?

If power is put to gray wire back at frame rail near pump it will run and engine will start. Had no ground to terminal 35 of relay. Replaced PCM and got ground. Still have no bat to terminal 35. Have jumper-ed term 30 to 76 (wire that is supposed to run to fuel pump and pump is not energized). Checked ignition 1 and ignition 2 fuses and are okay.

What does a fuel pump circuit malfunction mean?

A circuit malfunction indicates there is a problem in the circuit, not necessarily in the sensor or actuator, in this case the fuel pump. Do not jump to replace anything unless it has been tested and found faulty. For example, replacing the fuel pump will not solve this problem unless the fuel pump is shorted internally.

Why does my fuel pump not prime when I turn it on?

Pulled fuel pump relay and put in a jumper wire to run the fuel pump and it started. Put the fuel pump relay back in and it starts and drives, but the fuel pump still doesn’t prime when turning the key on. I’m afraid that after sitting overnight, it will once again refuse to start.

What causes a fuel pump to die before filling up?

If you make a habit of running your tank all the way to empty before filling up; your fuel pump will most likely die before its designed lifespan. This is due to the fact that when you shut off the engine with a low fuel level; the fuel can drain from the priming chamber designed into the fuel delivery system.

Why is the fuel pump and relay not working?

The ignition circuit, which includes the ignition switch, controls power to many components, including the fuel pump and relay. If there is an issue with the switch or the circuit, perhaps a wiring problem, then power to the fuel system may be cut off.

When is it time to replace your fuel pump?

Like any device, however, fuel pumps can and do eventually wear out after thousands of miles of use. If your car struggles with weak or inconsistent power, it may be time to replace the fuel pump on your car. Have you ever had to deal with a failing fuel pump?

Why did I have to change the fuel pump?

I had to change the pump because it had failed, no pressure or electrical humming. Make sure the fuel injectors are pulsing as oldtimer mentions. Even if the injectors are pulsing it won’t run with only 10 psi fuel pressure. Just curious, do you have a check engine light?

What are the terminals of a fuel pump relay?

Terminals 86 and 85 are the primary side of the relay. It utilizes an electromagnet to close (connect) the secondary electrical circuit inside the relay. As a result, This electromagnet is activated by a simple; power (+) and ground (-) much like a light bulb circuit.

What are the problems with replacing a fuel pump?

Fuel filter; this should always be replaced with the pump because even a partially clogged filter is a pump killer. Stuck fuel pressure regulator. Restriction in the return line to the fuel tank. (Disconnect and try blowing through it) Fuel pump relay getting hot and breaking down.

How can I tell if my fuel pump relay is faulty?

2. Engine does not start. Another symptom of a faulty fuel pump relay is an engine that does not start. If the fuel pump relay fails the fuel pump will be left without power. The engine may still crank when the key is turned, however it will not be able to start due to lack of fuel.

What to do if your fuel pump is not turning on?

Look into your engine’s compartment in the power center to locate your car’s fuel pump. Remove its relay and give it a good shake. If you feel something rattling inside, then chances are that the relay has broken and you will need to replace it.

How does a fuel pump relay control the fuel pump?

The fuel pump relay is usually controlled by the ignition or Powertrain Control Module, and when switched on, will provide current to the fuel pump so that it may function. As the fuel pump relay controls power to the fuel pump, any faults with it can cause issues with the fuel pump,…

What does the fuel pump shut off switch do?

This device is analog to an electric circuit breaker, but only for fuel, not electricity. Many vehicles come with a fuel pump shut off switches. The inertia switch is a security measure implemented by car manufacturers to shut off the fuel supply in case of a car crash or accident where a vehicle comes to a sudden stop instantly.

How to test a fuel pump relay with a multimeter?

1 Turn off your vehicle and remove the key from the ignition. 2 Find the fuel pump relay in your vehicle’s fuse box. 3 Pull the relay straight out from the fuse box to remove it. 4 Clean the relay prongs with a wire brush. The fuel pump relay may be faulty or have a loose connection if it’s developed any rust or corrosion on the …

How do you disable a fuel pump relay?

Step 6: Open the vehicle’s hood to disconnect your battery. Take the ground cable off of the battery’s negative post disabling the power to the fuel pump and sending unit. Step 7: Locate the fuse box in the engine compartment. Remove the cover to the fuse box.

What to do if your fuel pump doesn’t come on?

Take the seat off and listen. If when hot the fuel pump doesn’t come on, first check that the relay clicks, if not you may have a bad relay. You can check by testing voltage at the 2p connector on the top of the fuel pump when you first turn the key: brown wire (+), green (-).

Why is my Chevy fuel pump not working?

The thick black wire is the ground. If the fuel pump has been replaced before, It could have had the connector replaced with the new style ( old style is square and the new style is more rectangle/flat) and where they splice the new connector in could have gone bad.

Where is the power wire on a fuel pump?

On the fuel pump connector, the gray wire is the power wire. The thick black wire is the ground. If the fuel pump has been replaced before, It could have had the connector replaced with the new style ( old style is square and the new style is more rectangle/flat) and where they splice the new connector in could have gone bad.

What kind of connector for fuel pump relay?

Grounds are usually almost ring connectors. A ring connector is a round connector that a fastener goes through and holds the ring connector securely this way. You might want to get some electronic connector cleaner at your local auto parts store. It comes in a spray can and is made by CRC.

Where is the fuse box located on a GMC Yukon?

The fuse block access door is on the driver’s side edge of the instrument panel. The center instrument panel utility block is located underneath the instrument panel, to the left of the steering column. The underhood fuse/relay center is located in the rear of the engine compartment near the brake fluid reservoir.

Where is the relay on a GMC 6.2?

Those “gem” threads answered it perfectly. Relay is above the spare tire. My 6.2 is strong and sexy, but it still needs help sucking it’s own gass. Lol It’s crazy how GM can make (what seems to me) pretty major mods by adding relays here and deleting fuses there, but forgetting to update the manual and fuse box diagram.

What to do if your fuel pump relay stops working?