Bit of a head scratcher here for any electronics wizards out there.
I have a SP1 here that isn't priming the fuel pump when the key is switched on.
Several things of note here.
Battery is charged and in good order.
The fuel cut relay tests correctly.
The bank angle sensor and relay test correctly.
I have tried a different ECM on the bike, same problem.
I know there is a problem on the fuel cut relay signal line.
First test: You are supposed to have no continuity between the brown/black wire and ground with ignition off - I have continuity. I have disconnected the ECM and checked for a short, there is no short in the harness, it seems like the short is through the ECM.
Second test: when you turn the ignition switch on you are supposed to get continuity on the same (brown/black) circuit for a few seconds (this is what causes the fuel pump to prime when the key is switched on), - I have no continuity when the key is switched on.
From this I can see that the ECM is supposed to earth the signal line to allow the fuel pump to prime when the key is switched on, but for some reason this is working incorrectly. I need to know what tells the ECM to switch the signal line to ground when the key is switched on. I believe this is the key for finding the problem.
Now as a point of reference, if I short the brown/black signal line with a test light and turn the key on the fuel pump runs (and keeps running, no longer priming but just on full time) and the bike will start. I can then disconnect the short I created while the bike is running and the bike will still run. However once the bike is switched off I will have to repeat the short to get the bike running.
I know on some CBR's etc, there is a zener diode on the base of the ignition switch that can cause the fuel pump not to prime if the bike is hotwired, as it reduces the fuel pump voltage down to 9volts instead of the normal 12v. Is there something similar on the SP1's? I have taken the plastic plate of the bottom of the ignition barrell but couldn't see any zener diode there.
Any help would be greatly appreciated! Feel free to ask any questions, I am sure I would have left out some info you may beed.