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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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1) Do you hear the fuel pump run for 3 seconds then turn off ?
2) Does the bike have a security system ?
3) Does the bike have a FOB ?
4) Does the key symbol go off after several seconds ?
 

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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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Sorry, it does have a security system. The previous owner just never used it and didn't mention anything about it at the hand off. Change battery in FOB?
Yes, especially since the previous owner didn't use the security. Try that first to see if the red key goes away, then the engine will start ... whoop dee do !!! Maybe.
 

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No joy. Red key goes away but still won't start. Still have engine light. Do I have to reset something or push the fob button a certain number of times?
If the bike is set to the security mode the turn lights will flash several times. Also the engine won't crank over when in the security mode. If the engine light remains lit indicates there's a current coded condition. If still no spark after everything has been replaced except the start relay, that's what's left.
Stop switch is on ? You still maintain the engine cranks over but has no spark ?
 

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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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Yes ignition mod is ECM. If you search your particular model online for wiring diagram, you should be able to find the HD copy. Hayne's is not always accurate. It sounds like you have a connection issue to me. Ignition Mods don't go up often, most times when they are replaced it out of desperation. I would recheck all connections, spray with electrical contact cleaner, plug in and out several times to scrape away crud.
 

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Re-read this thread and noticed nothing was mentioned about the bike's battery ! A fully charged battery will measure 12.8> volts static. I would charge the battery then take it to get load tested at the local auto parts store.
An under charged battery will supply enough voltage to crank the engine over but not have enough volts to supply the ignition system, ignition cutoff at around 10.5 volts DC.
 
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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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