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Discussion Starter · #1 ·
Bought from a friend, Started and ran fine for a few weeks then started giving me intermittent hard starts.
Replaced oil,filter, battery, plugs , and wires. Problem seemed resolved for a while . Then hard start , stalling but would restart after sitting for a while. Replaced fuel pump, filter, regulator , lines, check valve assembly. No spark. Replaced Crank position sensor. No spark. Checked coil. Seemed bad by Ohms measurement. Replaced coil. no spark . ( I checked with a plug in the cylinder and a spare plugged into the plug wire so that there would be compression)
Check engine light comes on and goes off. Key symbol comes on indicating code in memory but when I do procedure to retrieve codes I don't get any. Any suggestions? ECM? Starter relay? Whats "upstream" from coil?
Thanks in advance
 

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Discussion Starter · #3 ·
1) I hear a buzz when I first turn the ignition switch ( looking in the tank it appears there is fuel in the lines
2) No security system
3) Yes FOB ( got a flash whe I pushed the button
4) Yes key symbol goes off, egine light stays on
 

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Discussion Starter · #9 ·
Yes engine cranks over fine, just no spark. Stop switch on. According to Haynes manual I need to be worrying about ECM. Hope not! Unobtainable! The name (Start Relay) would make you think the starter wouldn't turn over if it was defective. Are you implying it also controls voltage to the coil?
 

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Discussion Starter · #12 ·
One schematic I saw would seem to support the contention that the start relay only influences the power supplied to the starter. The starter turns over fine. I haven't seen the bank sensor mentioned in troubleshooting algorithms but I have seen it mentioned in forums about the jiffy stand blocking ignition so I have tried having the stand up and the bike vertical. No difference. In troubleshooting ( Haynes Manual) it talks about the "Ignition Module" is this in the ECM?
I checked all the wiring connections and couldn't find anything obvious but one time after unplugging and replugging everything it did "try" to start.
 

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Discussion Starter · #18 ·
Ok I will check it but it is a new battery and I have been putting a trickle charger on it in between attempts.
Also, I cleaned and reattached all the connections I could get to and checked continuity in the wires between the ECM and coil. I have good continuity in the wiring.
 

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Discussion Starter · #19 ·
Hope this helps someone else in the future.
Schmidty, thanks for your help, you were partially correct and got me thinking.
Thank you also to Madmantrapper you got me looking at circuit diagrams.
It wasn't the start relay but it was the system relay.
When I finally got my service manual and traced out the wiring path, there is a circuit called " constant power" going to the coil. That explains why I wasn't getting spark. As an experiment I swapped the start relay and system relay and when I turned the ignition switch I could hear a robust fuel pump priming sound. Of course , because the good relay was in the system position the starter wouldn't work but I knew I was on to something. I ran to autozone and got the closest relay I could and when I got home and plugged it in the bike fired up! So the problem was a relay this whole time- I never saw this mentioned in any thread or service manual.
Sometimes it's the simplest stupid thing......
I guess I can cancel the ECM I ordered at the dealership.
 
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