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Discussion Starter #1 (Edited)
Just finished wiring the '05 K24a3 EMS into my Bertone X1/9.

Checked all the wiring connections as I went along. K-Tuner in '05 Accord ECU (so I could use TPS and IAC & regular TB)

The problem I have right now is that the main relay is not switching with key on or cranking, so I have no fuel pump, etc.,

Both the Main and coil relays are supposed to ground via E7.

I'm not sure where to start fault tracing for this. Are there other ECU terminals I should check for power, etc., that would be impacting this?

Couldn't find a PGM-FI fault tracing guide, maybe I just don't know where to look for it.

I'm assuming worst case is that the ECU I bought is dead.

EDIT -it was suggested the immobilizer circuit could be the problem - any suggestions as to how to check that?
 

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Immobilizer controls ground to the fuel pump relay on pin E17 (IMOFPR). If E7 is not grounding with ignition I would start looking at ECM ground/ignition. E9 should have ignition voltage, A4 and A5 should have ground. Looks like A8 should have ground as well.

Are you able to communicate with the ECM over OBD2?
 

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Discussion Starter #3
Thank you for the suggestions. I haven't wired the OBDII port yet - that's the last item I need to add. I will do that first then check ECU + - followed by scan tool
I used the stock EMS harness, so I'm assuming the A ground and power connector wires are all on the motor ,

The key -on feed E9 I can easily check, I added the I/O for the E and C201 connectors
 

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Discussion Starter #4
Think I found it! Went over the circuit wiring diagrams again. Found that the (15) feed that goes to E9 is supposed to come from the same fuse that feeds the f/pump relay 30, not the ouput side of the main relay, which somehow is where I put it. No way it will ever energize like this. Not sure how I got such an error, but that is definitely the case, looking at my wiring diagram/pinout schematics.

[IMG]
 

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That makes sense to me. ECU enables the main relay when it sees ignition voltage on E9. It would never get ignition voltage the way it was wired. Good find (y)
 

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Discussion Starter #6
Yes indeed! I was not looking forward to the possibility of it being an ECU/Immobilizer issue - I found a screenshot from a year or so ago when I set up K-tuner - I had disabled it at that time

 
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