Clarification about interrupt relay module and ECU function

[jako2005]

This is my first time to post to any discussion forum, so please excuse any displays of poor form I may perform.

I have a 2005 Yamaha fz6 fazer, and I'm having some electrical trouble that I can't figure my way out of alone. After rewiring the bike three times, and effectively chopping up the harness a right bit excessive, I finally had the thing starting about a month ago, and even got to ride it four or five miles down the road before it shut off and refused to start back up. The only way I could make it operate, even in that limited fashion, was by grounding the signal wire from the ECU to the fuel pump relay, and then installing a second relay switching the red with blue tracer wire up stream of the pump and injectors, and after the cutout relay module. I've studied the diagram extensively, but my limited understanding of the way In which a diode matrix functions, and my lack of full confidence in the entirety of the forty some odd splices I had to make on the harness has me freezing up and unsure of the methods I'm using to troubleshoot the issues on the bike. Anyway, the bike would run but having the pump constantly on caused engine flooding, smoke out the tail pipe, and the aforementioned inability to stay running or fire back up after a short period of functioning.
Fast forward to this last week, I bought a fleebay used wire harness and three that son-bish on there just to be met with the same problems I ran into before chopping up the last harness.
I haven't got pump prime. The blue with white tracer wire at the starter solenoid has battery plus, for some reason, and I cannot get this damn ECU to voluntarily ground that little omron relay in the black death trap box. I don't want to cut into this harness, but how often does an ECU, realistically, experience catastrophic failure? Also, if anyone could explain how the diode matrix works within the confines of the starter circuit cutoff relay, that would be very much appreciated.
Thanks for reading,
Jake

 

[Motogiro]

Welcome to this great FZ6 family!
First, do you have a service manual with the schematic? I have one (PDF) that I put notes on to help ID components and relays etc. when trouble shooting.
The unit you reference is called the, "Starter interrupt - cutoff relay assembly" Yes the dreaded diode matrix from hell. If you've done anything it doesn't like it'll open a diode and your in trouble. The matrix looks at neutral safety switch, clutch switch and side stand switch. It provides the safety protocols for running and starting the bike.
A replacement is around $35 It has diodes including a zener diode and 2 relays.
To be safe, I would advise you to not pull any circuit to ground while still attached to the ECU as the ECU may have that state high when not pulling it to ground.
You can force the starter but you will be violating safety protocols provide by the matrix and the ECU. In addition don't pull the red w/white tracer wire at the starter relay to ground if that wire is connected to the ECU.
The fuel pump has its own pressure regulator so it shouldn't cause a problem unless it's faulty.
If you have 2 areas like fuel pump and starter it's probably Keanu Reeves messing with the Matrix.
How is the lean angle switch? If not attached properly if could stop the bike.

 

[jako2005]

Moto,

Thanks so much for the detailed reply. I work in construction, and as the air gets hot, so does business, so I haven't been able to dedicate any time to the bike until now.

Ill do the test on the lean switch how it sits right now, and verify it's good. Although, both start and FI are not working properly, so I assume the issue is somewhere in the wiring that affects both internal relays. The main switch is a tricky, too. I'm looking at a schematic, and if I'm to understand this correctly the switch will bridge the thicker (12+), and the thinner (12-) together, this activating the various sensors on the bike. It looks as though the ground path provided to the clutch switch, and then on to the module originates at the ECU via the white with blue tracer wire. Does this mean that the ECU can inhibit grounding that circuit if some other problem is sensed? Or could that pin on the board potentially experience catastrophic failure, and effectively castrate the entire electrical system? If so, would combining those thinner ground wires, and pigtailing then to ground solve my problem? I really don't mind making alterations to the harness, if I'm reasonably confident they'll be fruitful. I read another response you gave on a different post , and it sounds like my forced starter action via push switch was not pertinent, given that it not only bypasses the sensors but completely side steps the module altogether. So I can return all that to stock no problem.

I just want this damn thing to run. I've had so much fun learning to ride on this bike!

Thanks for all the help thus far!

Jake

 

[Motogiro]

Without knowing exactly what has been rerouted as far as present configuration from stock wiring, I would be giving poor advice.
You must be somewhat familiar with reading schematics, following color code and voltage on wiring. Unfortunately wiring colors may sometimes be a little off/confusing because of fading or a color may change at a device plug. For example, the color coding at the wiring for the ignition switch changes at the plug to the bike harness. A color code may also change between manufacturing series.
Serious consideration must be given with computer controlled technologies as they can be destroyed or damaged instantly. If you are not familiar with system operations you need to get help from someone with experience. We can help to some degree but without knowing what has been done/ spliced or the ability to measure voltages, we wouldn't be very efficient.
Any advice given that violates safety protocols is only good as a test and not advisable as a solution to running the bike.
Do you have the Yamaha service manual?