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How does KPRO send signal after initial priming to fuel pump

Posted: Sun Jan 31, 2016 2:33 pm
by tmartin
I have a 2005 S2000 with KPro. The car suddenly died and after hooking up to review in kmanager I noticed the fuel relay comes on to prime and then turns off after 2 seconds as it should. However once I try to start the vehicle the fuel relay does not come on and the car does not start. I verified the below items. as well as checked the plugs which are dry.

Main relay seems to checkout fine with the below steps.

1. To test your Honda Main Relay, first connect Pin 2 (mine – Pin 6) terminal on your relay to the positive terminal on your battery and the negative to Pin 1 (mine – Pin 8) terminal. Now check for continuity between Pin 5 (mine – same) and Pin 4 (mine – Pin 7) of the PGM-FI relay. If your relay has zero continuity in this test, it will need a replacement, if there is continuity, go to the next step.
2. Connect your positive terminal to Pin 5 (mine – same) of your relay and the negative terminal to Pin 3 (mine – Pin 2) of your relay. Now check continuity between Pin 7 (mine – Pin 1) and Pin 6 (mine – Pin 3). If your relay has zero continuity in this test, it will need a replacement, if there is continuity, go to the next step.
3. Connect your positive terminal to Pin 6 (mine – Pin 3) of your relay and the negative terminal to Pin 1 (mine – Pin 8) of your relay. You will be checking continuity between Pin 5 (mine – same) and Pin 4 (mine – Pin 7) in this last step. If there is continuity after these 3 steps, your problems with your car lie elsewhere and your main relay is good.

After the main relay check I validated I had current going to the YEL/GRN #7 to the fuel pump which it does during the 2 second priming sequence but not during actual starting. I verified I have pressure at the rail.

I made sure A15 - GRN/Yel is working which it is as well as B1 and B9 from the ECU Yel/BLK wires to main relay.

Any other ideas? Can you explain if B1 and B9 are the two signals from the ECU which control both priming and fuel pump on from the ECU to the main relay which ultimately gets to the fuel pump?

Re: How does KPRO send signal after initial priming to fuel pump

Posted: Mon Feb 01, 2016 10:33 am
by Spunkster
What was it doing at the time it died, and what has recently been changed on the vehicle?

From Help, About what is the version of software you are currently using?

Re: How does KPRO send signal after initial priming to fuel pump

Posted: Mon Feb 01, 2016 10:51 am
by tmartin
Only thing I have done is new Kal file since last release of 4.2.0.0 so I could do some datalogging

I was driving 27 miles and all of a sudden the car died. I am able to connect to the ECU just fine and was able to see after initial prime of 2 seconds and then trying to start the vehicle the fuel relay does not come on in Kmanager. If it helps attached is a log I did trying to start the vehicle on the side of the road.

Re: How does KPRO send signal after initial priming to fuel pump

Posted: Mon Feb 01, 2016 11:39 am
by Spunkster
The current version is 4.2.3 so I would recommend that you upgrade to the latest version of software and try re-uploading your calibration.

Re: How does KPRO send signal after initial priming to fuel pump

Posted: Mon Feb 01, 2016 12:31 pm
by tmartin
Thank you I am in progress of doing this and will report back. Can you tell me how the ECU sends the second signal and on what pin after priming is done? So how does the fuel pump get signal once the starter is engaged. I want to make sure I understand this for testing purposes as well.

Thanks in advance.

Re: How does KPRO send signal after initial priming to fuel pump

Posted: Mon Feb 01, 2016 1:58 pm
by tmartin
Ok I updated KManager to the latest version as requested. I had the same results with trying to start the vehicle and was able to datalog the 2 second prime and then start attempt. Please see attached.

If you can explain how the signal from the ECU is sent to the fuel pump after the priming process then I can ensure I have covered that as part of my testing. I believe my testing so far has been thorough but I am sure you guys may have another idea to test.

Thanks again

Re: How does KPRO send signal after initial priming to fuel pump

Posted: Mon Feb 01, 2016 2:04 pm
by Spunkster
Since there is no RPM being detected you should check the wiring to the cam and crank sensors as that would explain why you get the pump to prime but not to stay on.

Re: How does KPRO send signal after initial priming to fuel pump

Posted: Mon Feb 01, 2016 2:06 pm
by tmartin
Will do and thank you

Re: How does KPRO send signal after initial priming to fuel pump

Posted: Mon Feb 01, 2016 7:18 pm
by tmartin
So I first tested for battery voltage on the ECU B connector for the following

Terminal 1 IGP1 - YEL/BLK has power with ignition switch ON
Terminal 3,4,5 INJ2,3,4 RED BLU and YEL wires should also see battery power with IGN ON but they do not.

Does this mean the ECU has an Issue?

Re: How does KPRO send signal after initial priming to fuel pump

Posted: Tue Feb 02, 2016 10:19 am
by Spunkster
Check continuity of your wires from inside the ECU to the sensor itself.

Re: How does KPRO send signal after initial priming to fuel pump

Posted: Tue Feb 02, 2016 11:17 am
by tmartin
I dont think I understand can you elaborate on the continuity test? Continuity of which sensor? And to be clear you are asking me to open the ECU and test from within the ecu on the specific sensor?

Re: How does KPRO send signal after initial priming to fuel pump

Posted: Tue Feb 02, 2016 11:40 am
by Spunkster
With the lid off use a multimeter to check continuity from inside the ECU where the wires come in to the end of the wires where they connect to the sensors.
Spunkster wrote:Since there is no RPM being detected you should check the wiring to the cam and crank sensors as that would explain why you get the pump to prime but not to stay on.

Re: How does KPRO send signal after initial priming to fuel pump

Posted: Tue Feb 02, 2016 12:14 pm
by tmartin
Understood thank you and I will report back on the results.

Re: How does KPRO send signal after initial priming to fuel pump

Posted: Tue Feb 02, 2016 6:29 pm
by tmartin
So I checked the wiring to the cam and crank sensors plugs back to the plug at the ECU and both have continuity from one end of the plug to the other. I did take ECU cover to test as well but even with the cover off the prongs are covered by foam and I did not feel like screwing that up.

I tried to look up info on how to test the sensors themselves but didnt see anything. If you know of a test I can do on them directly I am all ears. I am stumped on what to do next here.

Re: How does KPRO send signal after initial priming to fuel pump

Posted: Tue Feb 02, 2016 7:44 pm
by tmartin
SO I am very interested in upgrading to KPro 4. Would it benefit me to send this ECU to you guys overnight with the upgrade form and have you guys first check it out and then if it checks out upgrade it as well? I would love to run a PLX wideband as long as I can get lean cut and be able to datalog which I believe I can running analog. I figure the car is down so why not. Then at least I can rule out the ECU which I do suspect at this point. I will however continue to test whatever I need to and I am open to your suggestions.