Hey guys, I'm hoping someone can please help me out here. I've done some research but have found many different solutions from others that didn't work for me.

So I have a 92 civic dx ODB1 chipped P28 with an LSV swap and the motor cranks but does not start. The fuel pump doesn't prime and I have a solid CEL for Code 0 which is for the ECU.

First I started off by getting another main relay but still no start. After that I was able to borrow a friend's known good ECU but still no start. I jumped the fuel pump wires from the main relay and it turns just fine so it is not the fuel pump. I've checked my grounds, especially on the thermostat housing, cleaned them make sure they're tight but still no start. I also checked the fuses under the dash which are (correct me if I am wrong) 18 & 24 and 38 in the engine bay and they're fine. Even tried replacing them each with another fuse just in case but no luck.

I believe my issue is the ECU is not getting the power it needs and by doing some research I think my problem might reside in the ignition switch. However, I couldn't find much online from others. If someone could please point in my in the right direction on how to troubleshoot it or by-pass the ignition switch to see if that is my problem or tell me what else it could be.

Please and thank you in advance!

 

Check fuses 24 (dash) and 31 (hood). Do you know where they are located?

Provide additional details about this^ test. What exact pins/wires in the main relay connector did you jump?

 

Thanks for the reply, I didn't know someone was going to reply to fast! lol

My plans tomorrow after 1:00PM EST was to hopefully tackle this problem so I will check those two fuses tomorrow and I don't remember which wires exactly of the top of my head but I will let you know tomorrow as well.

Thanks for the help!

 

You need to do two separate jump tests on the disconnected main relay connector:

Jump pin 1 to pin 7 (key off)

Jump pin 5 to pin 7 (key in ON-II)

The fuel pump should run for both tests.

 

 

 

See diagram in my previous post.

 

 

 

Nice work. Are you up for few more electrical jump tests on some ECU connectors?

 

If you don’t mind, yes! I’m dying to get the car running again.

 

Reconnect the main relay.

Disconnect ECU connector A.

For ECU connector A, use a wire to ground pin A7 or A8 (whichever is attached to a Grn/Yel wire) to the metal frame under the dash.

Turn key to ON(II).

Does fuel pump run?

 

 

 

Great. This^ tells you that the main relay circuit is operating as intended by Honda, and points to a problem with the ECU or ECU circuit.

Next tests:

Disconnect ECU connectors A and B.

Turn key to ON(II).

Measure voltage to body ground at pins A25 and B1 (Yel/Blk wires).

Turn key OFF.

Measure continuity to body ground at pins A26 (Blk/Red wire) and B2 (Brn/Blk wire).

Post the multimeter readings.

 

Perfect

 

 

Looks fine. Just curious what you used as the ground source for A26 and B2.

 

 

That's fine.

Tightly reconnect all connectors.

Crank engine.

Does it start? If not, do you still get code 0?

 

 

Details?

 

Turn key OFF.

Turn key to ON(II) [don't crank]

Does pump still fail to prime? Does CEL remain on steady? If so, does CEL also remain on steady when you jump the service connector?