changed the fuel pump relay and now no prime

[quickdiversion]

OK this is weird.
I have wired my fuel pimp in a stand alone circuit and it has worked fine for 5 years now. The car was having issues shutting down after the timer clicked off and I could hear the relay clicking around a lot so after dealing with pulling the fuel pump fuse to turn the car off for about 4 months, I decided the replace the relay.

After replacing the relay, it won't prime.
The power line works I know because if I connect it to the pump line, it primes.
I check continuity from my signal line back to pin #104 I believe it is, the black and pink line, and I have continuity.

This is a ground switch signal so when I have the car on and check the for continuity to ground, I do not have it...

did I damage the ecu?
or what can I check to see is going on.
everything else works fine , the ecu works fine as I can tell, because nismotronic is reading everything like normal and no error codes.


I'm lost, it worked, than it didn't.

[cotbu]

You should have 2 relays for the hotwire mod, usually the oem unit and the aftermarket unit. so which relay was faulty? and if you still use the oem relay check the fuse and that relay as well. Pin 104 should be grounded by the ecu and you should have continuity.

open up the ecu look at pin104 and it's trace, if that is burnt it can be repaired, but you need to find out what caused the problem first or the repair might make fire.

[Smurf_240SX]

That happened to mine, about a week ago. I checked all fuses, relays, the pump everything worked once I swapped with my spare ECU. I opened up the old Ecu an you could smell the burnt diodes lol

[quickdiversion]

You should have 2 relays for the hotwire mod, usually the oem unit and the aftermarket unit. so which relay was faulty? and if you still use the oem relay check the fuse and that relay as well. Pin 104 should be grounded by the ecu and you should have continuity.

open up the ecu look at pin104 and it's trace, if that is burnt it can be repaired, but you need to find out what caused the problem first or the repair might make fire.

There is no reason to run 2 relays.
I made the setup myself. There is no relay in the box, I jumped the signal frm pin 3, black and pink wire, and ran it to the rear of the car.

[quickdiversion]

That happened to mine, about a week ago. I checked all fuses, relays, the pump everything worked once I swapped with my spare ECU. I opened up the old Ecu an you could smell the burnt diodes lol

**** I hope it didn't burn the ecu, I'm sure it did, but I hope not. I just had nismotronic put on this...

[cotbu]

so you put an inline fuse in your new circuit?
Your ecu must not be triggering it then, just test it with a parallel wire to trigger the relay, from the ecu.
With nismotronic you should be able to trigger the fuel pump relay for testing, nistune can.

[quickdiversion]

so you put an inline fuse in your new circuit?
Your ecu must not be triggering it then, just test it with a parallel wire to trigger the relay, from the ecu.
With nismotronic you should be able to trigger the fuel pump relay for testing, nistune can.

Yup, there is a new inline fuse with it.
I just opened the front and back of the ecu and both look clean, no sign or smell of burning. and looked at it under a magnifine glass.

here is the only picture that cam out of the what might be a burnt cap, but I can;t tell if it is just covered in clear like everything else and the clear bubbled or the cap popped, cause it doesn't smell and it doesn't look like any cap pop I have seen.

http://i12.photobucket.com/albums/a206/quickdiversion/20140513_192110.jpg (http://s12.photobucket.com/user/quickdiversion/media/20140513_192110.jpg.html)

[cotbu]

When capacitors blow the top usually blooms, but the cap itself can explode if overcharged
Run that wire from the ecu to your relay trigger, that will let you know if the ecu is good right away, as long as the rest of your circuit is good

Ps you'd probably have noticed if a trace was burnt, following pin 104

Sent from my Highly Tuned Galaxy S3.4!!!

[quickdiversion]

When capacitors blow the top usually blooms, but the cap itself can explode if overcharged
Run that wire from the ecu to your relay trigger, that will let you know if the ecu is good right away, as long as the rest of your circuit is good

Ps you'd probably have noticed if a trace was burnt, following pin 104

Sent from my Highly Tuned Galaxy S3.4!!!

I have continuity from plug side of pin 104 to my signal connection for the relay

I get nothing from pin 104 is the problem. Following the diagnosis table from the pdf I should have a voltage between ground and 104 with key in on position and I get zero across the board

[cotbu]

I don't get anything from pin 104 with koeo either

Doing what I suggest Will confirm faulty ecu, you can also run a manual ground trigger to your relay if the ecu is toast just to get you running.

The pin 104 should not ever see 12v source

Sent from my Highly Tuned Galaxy S3.4!!!

[quickdiversion]

I don't get anything from pin 104 with koeo either

Doing what I suggest Will confirm faulty ecu, you can also run a manual ground trigger to your relay if the ecu is toast just to get you running.

The pin 104 should not ever see 12v source

Sent from my Highly Tuned Galaxy S3.4!!!

I know I should not see a voltage source, but the manual says you should, which is odd. I did also check from a continuity signal from pin 104 to ground with the key in the on position.

I kinda was thinking about just doing a separate switch just for a small safety feature.