How to Bypass Fuel Pump Relay

When you know the fault in your car and know how to repair it, it saves you from waiting for hours for the mechanic. That also tells you how much you know about your vehicle!

Oftentimes the main function of the car needs assistance for secondary approach. Therefore, it’s important to know how the internal machinery works. For example the fuel pipe relay is the central part of the fuel injection system. 

However there are times when it gets faulty or malfunctioned for whatever reason. 

So, knowing the proper steps for bypassing the fuel pump relay is what makes or breaks the deal. Sometimes if you mishandle the fuel pump relay it can be dangerous as well as expensive to repair.

If you have decided to bypass the fuel pump and rely on your own, this post is going to be a helpful read.

How does the bypass fuel pump relay work?

If I say fuel pump is the car function as a heart work in the human body it won’t be an exaggerated statement! The fuel pump pumps the fuel that is needed for the internal combustion engine ICU.

In vehicles or cars, the fuel pumps usually malfunction when the electrical component (fuel pump) does not work. If it has stopped working, here is how you bypass the fuel pump relay.

How to bypass fuel pump relay

You will need

  • 10 mm socket wrench or socket ratchet set
  • Wire cutters or jumper cables

Unplug fuel pump

Unplug the fuel pump relay. You will find it right under the vehicle hood into the power distribution center/relay box or TIPPM plastic box. there will be fuel pump pins that are inside the terminal connected to the parts to the other end.

Use the copper wire

Now use the small diameter copper wire 4 to 5 inch length and join the terminals. You need to strip the insulation at each end of the copper wire. It should be about 1/2 inch size before connecting.

Bypass the fuel pump

Bypass the fuel pump

In order to bypass the fuel pump relay use the single cord and connect it to the terminals corresponding to contact switch pins viz. 87 and 30. Use Pins 3 and 5 for some vehicles’ fuel pump relay.

If you have done it right, you should hear the fuel pump priming or buzzing sound after connecting the terminals with jumper wire.

Is it safe if I bypass the fuel pump relay?

Yes, it is totally safe to bypass the fuel pump relay if your vehicle is in need of. The fuel pump relay is there to offer voltages for pumping the relays. If the voltages are not enough, your car will stop working. So bypassing it is safe. However, it’s always better to get professional help or assistance if you are doing it for the first time.

How do I know that the fuel pump relay has gone bad?

How do you know if the fuel pump relay has gone bad? This question certainly pops into one’s mind who is dealing with a stalled car. There are few signs that tell you about a bad fuel pump relay. If you see them it’s about time for bypassing or maybe taking your vehicle to the mechanic.

Engine won’t start

Engine won’t start

If the fuel pump relay has gone bad, there won’t be any power to supply the fuel pump. As mentioned above the fuel pump sends voltages, so if it is faulty, the engine won’t turn on.

Read Also: My Car Starts Sometimes and Sometimes It Doesn’t

Silent fuel pump

The pin-drop silent from the fuel pump is now dead. The working fuel pump relay should have a priming sound. Usually the fuel pump starts priming for 3 seconds after the car starts. So if you don’t hear any noise it means it has gone bad.

Constantly priming

Conversely, if the fuel pump is continuously priming it is not a good sign either. The constant priming will drain the battery until it completely becomes discharged/dead. Therefore, the vehicle won’t start when you turn it on.

The engine light

The engine light

When the fuel pump relay is faulty, there won’t be any fuel pressure in the supply for obvious reasons. So another sign for figuring out if the fuel pump relay has gone bad is you need to see the CEL light on the dash. If it glows it means there are issues pertaining to the engine component.

Other Signs include

  • High mileage
  • Too much starting time      
  • The car dies while driving

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