If you have a Chevy truck with a problem with a fuel pump, you should know how to jump fuel pump relay on Chevy truck.
When you are in the middle of the road with no service anywhere near, you can try and bypass this problem by reconnecting the fuel pump relay.
To do so you only need to follow a couple of steps that we will show you later on.
What is a fuel pump relay?
A fuel pump relay is an electrical component found in all cars that have an internal combustion engine. It is usually found with the fuse box and is packed in a black box.
The fuel pump relay is an essential part of the vehicle, and without it, the car couldn`t start. When a car is started, a current is powering the relay just long enough so the fuel pump starts working.
After that, the relay shuts down, and the current is delivered by the unit that supplies the oil pressure.
The fuel pump relay is again activated when shutting down the car, just long enough to turn off the pump.
What does a fuel pump relay do?
The only function of a fuel pump relay is to deliver the current to the fuel pump. If it is working properly it should deliver enough power to start the pump, and not overburn it.
Without the pump relay, a fuel pump could easily overheat because it requires a lot of power to work. A relay is there to deliver the right amount of power.
A car can`t work without a properly functioning fuel pump relay.
Signs of a bad fuel pump relay
There are 4 common signs of a bad fuel pump relay:
01. Stalling of the engine
During the ride, if the car suddenly stalls and eventually stops, that is a sure sign that there is a problem with a fuel pump.
In some cases, the car can be started again – then go straight to the mechanic. If the car can`t start, then the fuel pump is completely dead.
02. The engine can`t start
An often symptom of a malfunctioning fuel pump is that the car can`t start. The engine may produce a sound when turning the key, but it will not start.
That is because the fuel pump doesn`t receive any power, and the engine can`t start without fuel.
This can be only one reason for the engine start problem. If it is not the fuel pump, do a detailed check of the car.
03. Loss of power
If there is a sudden loss of power during a car ride, a faulty fuel pump may be the culprit.
Sometimes a car can run for some time even with a malfunctioning fuel pump, but the lack of power will eventually come. If you notice a lack of power, don`t wait for a car to completely stop by itself.
Stop, and check it yourself, or go to a mechanic.
04. No humming from the fuel pump
When starting an engine a fuel pump produces a humming sound. It can be heard from the inside or outside of the vehicle, when near the oil tank.
If the pump doesn`t receive electricity it won’t start and will remain silent.
Fuel pump relay diagnosis process
If you think that there is a problem with a fuel pump relay, you can check it yourself. Following these simple steps will give you some idea about the problem you are having.
01. Park the car on the level ground
If you have a garage that is on level ground, that would be perfect for the test.
02. Turn on the ignition key, but don`t start the car
When you turn the key the pump will make its humming sound. That sound would be better heard if the car is parked in the garage.
If your car has a very silent fuel pump, then this step will not help. Proceed to the next one.
03. Manually find the fuel pump relay under the hood
Open the hood and search for the fuel pump relay. In most cars, it is located in the fuse box that is usually black. Remove the cover of the box and find a diagram that shows all electric installations and fuses.
If you can`t find it, check the user manual of the car. If that didn`t help, try online assistance or a car electrician.
04. Disconnect the negative cable from the battery
This step is for those that heard the sound when turning on the ignition key. After removing the electricity from the car you can continue with the operation.
05. Removing the fuel pump relay
Without electricity, it is safe to pull out the pump relay. It is cube-shaped and connected with electrical plugs.
In some cases, you will need a flathead screwdriver to disconnect the fuel pump relay.
06. Visual inspection of the fuel pump relay
Even if you don`t know what to look out for, check if there is any visible damage made to the fuel pump relay.
07. Use a multi-meter tool to test it
Multi-meters have a lot of testing options, so be sure to choose resistance mode. First, feed the relay with 12V power. Connect the ground of the relay with the ground of the power supply.
After that connect the probes of the multimeter with the load and battery pins on the relay. There are 4 pins on the relay (load, battery, ground, and input voltage), so be sure to connect the multi-meter properly.
If the multi-meter is beeping when touching the input voltage that is a sign that there is continuity. If there is none, then the relay is broken.
07. Replacing the relay
If you determined that the relay is faulty buy a replacement one and install it.
Materials needed to jump fuel pump relay
If you are a DIY person this operation will not be that hard for you. Jumping a fuel pump doesn`t even require a lot of materials and equipment.
A ratchet set, wrench with an open end, and extension cables are enough to jump a fuel pump relay. If you want to replace it, with these numbered tools, just add a new fuel pump relay.
But if this type of work is something unfamiliar to you, it would be best to find a mechanic that can finish this replacement very easily.
Step by step guide: How to Jump Fuel Pump Relay on Chevy Truck
Following this easy instruction, you will be able to jump-start the fuel pump relay somewhere between half an hour and an hour.
01. Locate the relay
Relay is found in the engine bay. Before starting be sure that the car is parked on a flat surface. In most Chevy models it is located near the fuse box.
The relay is placed in a black box that is made of plastic. The relay is marked with a label so be sure to check it before proceeding.
02. Disconnecting the battery
Before conducting any work with electricity the battery needs to be disconnected. Remove at least the black, negative cable, and if you want, remove both of the cables.
03. Use jumper cables
Connect the end of the cables, and properly pair them. Connect the red jumper cable with the red battery end. Do the same with the black.
Don`t forget to avoid any contact between cables and anything made of metal. Then connect two pins with the ends of the copper wire.
Look for the pins in the upper left and lower end corners of the relay center, and connect them with wires.
04. Time to start the engine
When you start it, don`t drive it! Just leave it running for about 15 seconds. Turn off the engine after you reconnected everything the way it was before you started.
05. Check the fuel gauge
After you turned off the vehicle check what is the fuel gauge shows. If you have done everything properly you should see the progression of the colors in the fuel gauge.
First comes red, then yellow and at last green. If the fuel gauge shows green right away then something is not done right.
Here you can check out a video that will help you in this operation. It is explained step by step and it is easy to follow.
Alternative methods to jump fuel pump relay
If you don`t have jumper cables there is an alternative way to jump the fuel pump relay. It will require some work with pins.
- The first pin should be disconnected from the center of the relay. Then take a 5-inch piece of copper wire, and remove about half of the insulation from it. Be sure that you removed the insulation from both ends.
- Start the engine. Like in the first method, turn off the engine after 15 seconds, after reconnecting everything. After the next car start, the fuel gauge must change colors – from red, and yellow to green.
Fuel pump relay replacement cost
This varies, and it depends on the vehicle and the mechanic. Specifically for a Chevy truck, the cost of replacing a fuel pump relay is around 100$.
Most of the cost is for the mechanic’s labor, while the pump relay can be found relatively cheap. In this video, you can check out how to test and replace a fuel pump relay.
FAQ about How to Jump Fuel Pump Relay on Chevy Truck
01. Which fuse is for the fuel pump relay?
You should lookout for a fuse box that can be located either under the hood or under the dashboard. First, look under the hood.
Look out for a black plastic box near the battery. Look under the cover of the box for the diagram that shows relays, fuses, and circuit breakers. The fuel pump relay is controlled by a small black relay.
Look near it for a 10 amp fuse with a label that shows fuel, fuel pump, or an f/p. If there is none then you should check under the dashboard. The markings are similar to the fuse box under the hood.
02. What causes a fuel pump relay to malfunction?
While sometimes a relay can be damaged because of the power surges, in most cases the problem is old age.
Depending on the quality and how the car is driven, a fuel pump relay can last 100 thousand or 200 thousand miles. And that is a lot of ignition key starts.
Also, a faulty electrical installation can burn out the relay with a high voltage current. If you often have problems with a fuel pump relay, check the installation.
03. Can a car run with a bad fuel pump relay?
It all depends on the extent of the damage to the fuel pump relay. If the damage is smaller you will be able to start the car after a few tries, but there will be symptoms of the bad fuel pump relay.
The engine will stall and lose power, and eventually, the relay will completely stop working. Then the engine will not receive any fuel and will stop. After that, the car cannot be started.
If you notice any symptoms of a faulty fuel pump relay, go to a mechanic and resolve this problem before your car lets you down somewhere on the road.
04. Should I jump the fuel pump relay if it is faulty?
Driving a car with bypassed fuel pump relay is not good in the long run. The reason for jumping the relay is to check the electrical installation.
If after jumping the relay, the pump works, then you have an inoperable fuel pump relay. If the pump after the jumping doesn`t work then the problem is in the installation.
Either way, you should check your fuel pump and a relay. A well-maintained car is the only one that will always get you where you intended.
Problems with a fuel pump relay are common. Are they hard to resolve? No. Are they expensive? No. Is a working pump relay a must?
Yes, it is! If you notice problems with the fuel pump relay that we mentioned in the article you shouldn`t waste any time.
Don`t allow yourself to drive around with a damaged fuel pump relay. Don`t drive with a jumped relay either. You will get nowhere. Go to a mechanic, or follow instructions to replace the relay yourself. Drive safe!
Hello, this is Wesley Shelton, currently working in a car restoration company for over 5 years. Before that, I was a worker at a small car repair shop. As I was a car freak from a young age and worked as a professional for over half a decade, I think I now know pretty much everything about every car and its parts. To establish my name as a professional and help others by sharing my knowledge, I’ve created this website, which I work on whenever I get free time. I hope you’ve enjoyed my informative blog!