Fuel Pump Wire From Ecu

[skidmark]

Hi guys I am trying to wire my fuel pumps in my rb20det powers Datsun 240z.

They work if I send 12v straight to them from the battery, but I can't seem to get them working with a relay.

I have flowed several different diagrams from

Google with no luck.

My main question is, is pin 18 on the rb20 ecu a trigger with +12v or earth. It currently has no power coming from pin 18. Just need to know its not fried.

Cheers

Mick.

[Dobz]

I imagine the trigger would be an earth. Get a multimeter and test the continuity of the wire to the chassis as soon as you turn the ignition on.

[skidmark]

Ahh right so I would need 12v switched on the others if of the coil pin on the relay through to the ecu wire and then constant 12v through to the 12v wire on the points side of the relay. Does this sound right?

[Dobz]

Yeah with the ecu wire just on the other side of the relay coil to control it. Still check for continuity to earth through the ecu wire to confirm it works.

[jiffo]

Dobz is correct. Pin 18 grounds to trigger the fuel pump relay.

Don't forget your ecu will time out after 5-odd seconds, so then no more signal to the fuel pump.

You have to trip the start signal for the fuel pump timer to re-start.

[skidmark]

Cheers guys. It has continuity so now I just need to find I suitable switches 12 v. I just checked the one I was using and it only has 10v. No wonder it won't work.