94 Honda civic lx no power to fuel pump

Ruben6805

New Member
@RonJ as soon as I try it I will post results. Thanks again for your help!
 


Ruben6805

New Member
No it's not the pump, if you read earlier post, I'm not getting power at the harness that connects to the fuel pump. When I jump the terminals where the main relay goes, the fuel pump comes on,
 

iSpeed

New Member
ever thought about a new harness?...or wire it up to a switch?

edit: do you have friends that are able to let you use their ECU so you can see if thats the issue??
 

Ruben6805

New Member
Never mind my nieces car is a 96 so I can't use the ECU off of that one. Guess I'll have to try to buy one and see.
 

RonJ

Banned
Start your search by scouting the ClubCivic Marketplace and similar forums in other Honda forums.
 

Ruben6805

New Member
So I found the wire going to the ecu from the harness and it seems I'm getting power out of ther but no power to harness. I did continuity fom harness at fuel pump to main relay harness and got continuity. I tested the relay and it tested good.
 

RonJ

Banned
So I found the wire going to the ecu from the harness and it seems I'm getting power out of ther but no power to harness.
Can you be more specific here^? What wire?

--------------------------

There are more tests if you are up for them.

Have you tried this test:

  1. Remove ECU connector A.
  2. Turn key to ON(II).
  3. Use a piece of wire to ground terminal A7 or A8 in connector A to the metal frame under the dash.
  4. Does the fuel pump run?
http://www.phearable.net/tech/wiring/obd1.pin.schematics.gif



.
 

Ruben6805

New Member
It was a white wire with blue I believe. Do you have a pic diagram of which on is A7 or A8? I'll try tomorrow when I have light.
 

RonJ

Banned
It was a white wire with blue I believe.
You mean the Wht/Blu wire from the 7.5A hood Back Up fuse? If so, the fuse is probably blown. Check it.

However, a blown Back Up fuse would not prevent the pump from priming. It would just prevent the ECU from storing information like codes.

Do you have a pic diagram of which on is A7 or A8? I'll try tomorrow when I have light.
Click the phearable link I posted.
 

RonJ

Banned
Ok so I ran the wire from a7 to ground and I got power at the fuel pump.
This^ tells you that the main relay gets power from the hood fuse box and the ignition switch and that it works properly - no problem there.

There's a few more voltage and ground tests to do from the ECU connectors - not too difficult. Are you up for it?
 

RonJ

Banned
With main relay plugged in, unplug ECU connectors A and B.

1) With key turned to ON(II), do pins A25 and B1 have battery voltage to body ground?

2) With key off, do pins A26 and B2 have continuity to body ground?
 

Attachments

Ruben6805

New Member
Ok so I tested a25 and getting 12v and b1 getting 12v. Also a26 continuity to ground good and b2 to continuity to ground is good. What's next? Please
 

RonJ

Banned
Last test.

Plug everything back in and then unplug the MAP sensor. Turn key to ON(II) and then measure voltage to body ground at each pin of the MAP sensor connector (wire harness side). Post the voltages you read at the Yel/Grn, Wht, Grn/Blu wire pins.
 


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