Crx Si Main Relay Through Headlight Wiring Diagram

I have an 87 Accord LXI. The car died while I was driving. I found the problem to be fuel related. The fuel pump was working because when I jumped the ignition to fuel pump, fuel rushed out like a pint/5sec or so(the only test I ever get fuel). The ECU was working cause my friend's 88 LXI, not quite the same ECU, started right away when I tried my ECU on his car.The main relay was also working cause when I tested the main relay(the same procedure as the one provided here), all contacts clicked and all continuity were available. I even tested with a new relay to eliminate the relay problem completely. However, when the relay is connected to its harness, it's not clicking, so I suspect the problem lies in the harness. I then tested the harness' pins for continuity using the information from here, http://www.tegger.com/hondafaq/mainr...ion/index.html . The following continuity test were done ; 1st test, between pin1(battery) and pin2(Ground). 2nd test, between pin5(Ignition) and pin2,
3rd test,between pin4(starter switch) and pin2, and 4th test, jumping pin5 to pin7(fuel pump).

When I disconnect the ECU, the relay harness test shows perfect result(as you supposed to get when a car is normal), but when ECU is connected, I got weird results and that's the reason why the relay was not activated(no clicking sound). There are 3 harness connected to the ECU, but only the connection of the middle one make the differences. Hope I didn't confuse anyone, the harness being tested is the relay harness, but the harness that (seems to) caused the problem(to the relay harness) is the ECU harness.

Here' s the results for the 4 key positions(off, 1,2, and start)
(Note: little low on the battery voltage, but it doesn't take much to pump the fuel)

A. ECU (middle) harness was NOT connected.

1st test Pin1(to Battery) & pin2(to ECU always ground)
11V, 11V, 11V, 9V

2nd test, pin5(to Ignition)& pin2
0v, 10v, 11v, 9v

3rd test, pin4(to starter switch) & pin2
0v, 0v, 0v, 6v

4th test, jump pin5 to pin7(fuel pump)
fuel rushed out

So, all good, but then

B. With ECU (middle) harness connected.
1st test Pin1(to Battery) & pin2(to ECU always ground)
10V, 10V, 0V, 0V

2nd test, pin5(to Ignition)& pin2
All no continuity 0v, 0v, 0v, 0v

3rd test, pin4(to starter switch) & pin2
-0.4v, -0.4v, -10v, 0v

4th test, jump pin5 to pin7(fuel pump)
fuel rushed out

So my question is have anyone seen this problem? Do you happen to know what are the middle harness' wires connecting to the ECU?
I thought to fix this problem I might have to replace the whole set of under-dash wires, any suggestion?

Some info that might be helpful, I just replaced the head gasket on the car. At the beginning, I saw the cooling fan, may be wires, making sparks a few times, but I drove the car anyway. I drove it about 100 miles since then. And a few days, about 40 miles, right before the car died, I had to replace the alternator.

Thank you in advance

The weary man

Source: https://honda-tech.com/forums/honda-crx-ef-civic-1988-1991-3/checking-main-relay-pics-2535047/

Posted by: darrenspedityoad.blogspot.com

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