Biggiesacks

I have been on and off toying around with different methods of doing the fuel pump hard wire, or second fuel pump addition. Traditionally this is done with a hobb switch to trigger the new relay, but I wanted to try and explore a way to drive the bypass / second relay from the ECU more directly. I have been posting about it in mrfreds rewire howto here: https://www.evolutionm.net/forums/ev...e-circuit.html

but i figured that information might get buried so i thought i would post it here. I have done some minor reverse engineering on the Stock ECU and have found that it uses Fuji Electronic F5033 Power mosfets to trigger the various relays in the car. Circled in Red is the one that triggers the high voltage relay in the fuel pump circuit


These mosfets have a rating of 1000 milliamps of continuous current. The Datasheet can be found here:
http://datasheet.octopart.com/F5033-...t-10902086.pdf

The typical 30amp bosch style relay draws around 130 milliamps @ 12volts to trigger. So if you wanted the ecu to trigger additional relays on an existing control circuit there should be plenty of headroom to do that without risking any damage to the ECU (when wired properly).