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TNT!hammond
24-03-2010, 23:07
Im trying to think of the best way to activate the fuel pump relay. I have removed the remix unit in favour for the Megajolt system. I know which wire from the relay switches it on when cranking is sensed but im not sure if my ecu will control it.

My ecu has
Programmable output 1 – open circuit until active, then grounded. 0.3A max. which is switchable at any given rpm. Im not sure if i can connect the brown wire from the relay to this output and set it to activate at 50 rpm. ?

would this work or is there a better way?

with thanks Hammy

Miller
24-03-2010, 23:22
Have you been on the main website?

http://www.autosportlabs.net/MJLJ_V4_vehicle_installation_guide

If you look towards the bottom you will see how to wire it, you will need to remove the original fuel pump relay and use a normal 40 amp four pin type.

If you need any help just pm me for my number:agree:

Chris:)

firstchoicegary
24-03-2010, 23:25
you cant beat some of the guys on here for the help and knowledge

Miller
25-03-2010, 00:03
Also, incase you have not seen it....

http://www.rtoc.org/boards/showthread.php?t=4723

What i did with emms megasquirt ecu was, remove the pins from the original fuel pump relay holder and just pushed them into the corect pins on the new 40amp one, so you do not even need to cut any wires to power up the pump.:)

I do not know if megajoilt is the same as megasquirt and that you ground through the ecu and not straight to earth.....you can see the diagram on this page for MS

http://www.extraefi.co.uk/Drawings/PDF_Files/WiringLoom_VR_Hall.pdf

Chris:)

tiff_lee
25-03-2010, 00:17
So you want the cranking of the engine to trigger the fuel pump relay?

Why not just use the oil pressure switch as the trigger?
Edit: mind you that method is probably a little crude and if you're using something like megajolt and it has the capacity to incorporate fuel pump control you may as well use it.

Have you had the megajolt up and running yet? just wondering how it compares to the standard dizzy and renix unit.

TNT!hammond
25-03-2010, 17:54
Thanks Chris , ill give those a look now.

Cant wait to get her started again and have some control on the ignition side :)