Jump to content
We Need Your Help! ×

IGNORED

How do I wire a 5 prong relay to a fuel pump?


0100

Recommended Posts

I need to wire a 5 prong bosch type relay to my aftermarket fuel pump. The relay is a 12V 30/40A

It looks like I should have:

1 wire to the +

1 wire to the -

1 wire to the fuel pump and

2 wires to the ignition

But what wire goes where?

The relay has a:

30

85

86

87

87a

What should I connect to what?

Thanks.

Link to comment
Share on other sites


I dont have the data here at work but often there will be a small circuit diagram embossed on the side of the relay.

Basically you want your switch (ignition) to put power across the coil in the relay to allow your source (battery) to power the output (pump).

If that fails, run a search on relays as those numbers for the contacts are fairly universal.

Link to comment
Share on other sites

For quick reference:

85 - is for your ground

86 - is from the switched source (ie: your ignition)

30 - is your power input (from alternator, battery, etc.)

87 - is your power output (in this case to your fuel pump)

87a - would not be used in this case

The 87a is the alternate power output. Relays are commonly used as a switching device. So the 87a output will power some other accessory when the main power is not switched to the 87 output. Did I make sense? Either way, it's not used in this case.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Who's Online   0 Members, 1 Anonymous, 777 Guests (See full list)

    • There are no registered users currently online
×
×
  • Create New...

Important Information

By using this site, you agree to our Privacy Policy and Guidelines. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.