Question about fuel pump

For discussing how to choose sensors and create a wiring harness for all Bowling and Grippo versions of the MegaSquirt® EFI controller.
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danekatie
MegaSquirt Newbie
Posts: 4
Joined: Tue Feb 03, 2009 1:02 pm

Question about fuel pump

Post by danekatie »

Im new to Mega squirt so please be gentle.

Pin 37 is labelled up as fuel pump

I am a bit unsure if this is a supply for the fuel pump (highly doubt though)

Or its a trigger wire for a relay? so it switches the relay to power fuel pump?

or is it a live into the ECU to say "fuel pump on"

im unsure!

thanks
66fb

Re: Question about fuel pump

Post by 66fb »

Or its a trigger wire for a relay?
MS grounds this pin to energize a relay that supplies power to the fuel pump. You would supply 12v to one side of the relay coil and take the other side to pin 37.
danekatie
MegaSquirt Newbie
Posts: 4
Joined: Tue Feb 03, 2009 1:02 pm

Re: Question about fuel pump

Post by danekatie »

not too sure, sorry if i sound thick

It grounds pin 37 to complete the relay?

unsure, could you explain a little more if possible.

many thanks

sorry if im been thick and not understanding the diagram
LeslieTroyer
Helpful Squirter
Posts: 35
Joined: Tue Nov 20, 2007 11:46 am

Re: Question about fuel pump

Post by LeslieTroyer »

wire one side of the Fuel Pump Relay coil to 12Volts (fused), the other side goes to pin 37. When the MS wants to start the pump, it will complete the circuit to ground so the FP relay pulls in. This seams "backwards" to most normal people, but electronics are better at sinking power, rather than sourcing them....

LEs
danekatie
MegaSquirt Newbie
Posts: 4
Joined: Tue Feb 03, 2009 1:02 pm

Re: Question about fuel pump

Post by danekatie »

brilliant

i worked it out finally today useing a couple of links, and a few testers.

and the above is what it is, but thanks for clearing that up.
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