1992 civic VX completely stock D15z1
It all started with my fuel pump not priming so i checked all my fuses (all of them) with a meter, they all check good. My bro has the same car so swapped main relays real quick, with no joy. I noticed the relays were not clicking over so i jumped pin 5 to pin 4 on the main relay disconnect and the pump primed. From there i checked for power at the main relay boths pins 5 and 7 got 12 volts but nothing at pin 2, i figured fuse 18 was bad swapped it out still nothing. Checked for continuity from fuse block 18 to pin 2 on main relay checked good. So i pulled the fuse out and shot for power at fuse block 18 and got nothing, so i traced schematics back to the integrated control unit but i have no idea where that is and what it does. So any insight on where this icu is or what it does would be great, also anything else i can try to get this thing going would be great. Thanks in advance for any help.

 

The main relay terminal numbers you mention don't fit with your car.

At the main relay connector:

Fuse 31 supplies constant voltage to terminal 1 in the main relay connector.

Fuse 24 supplies ON(II) voltage to terminal 5 in the main relay connector.

Fuse 18 supplies ON(III)/START voltage to terminal 6 in the main relay connector.

Terminal 7 in the main relay connector runs to the fuel pump.

Does the fuel pump run when you unplug the main relay connector and then jump:
-terminal 1 to terminal 7?
-terminal 5 to terminal 7 with key in ON(II)?
-terminal 6 to terminal 7 with key in ON(III) [disconnect starter for this test]?