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.

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.

Yes it does have a circuit diagram on the side of the relay, but it's not with me right now. I tried making sense of it but was confused.

I'll do a search to see if I can find any info.

Thanks.

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.

Great thanks.