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Discussion Starter #1 (Edited)
So today I've been having an issue with her starting... It has never died on me once started, so that leads me to believe it's an issue with just the starting circuit.

So getting on the bike, raising the stand, turning the key on, and then flicking the on switch usually results in the fuel pump priming.... However today it's not kicking on.(pressing the start button does nothing of course)
I've gone through and check battery connections, starter solenoid, fuse box, ecu connections, nothing seemed to help.

However after turning the key a few times and toggling the on/off switch, the fuel pump did kick on... however pressing the starter just resulted in a weak cranking of the engine for less than a second.

Any ideas? It's always run great before this with the exception of the bad CPS connection that was resolved.

EDIT: Going to check for shorting wires going to the pump.
 

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Discussion Starter #4
I measured the battery after having the headlight on for a few minuted(trying to flick the side stand up/down, and toggling the on/off switch) and it read 12.6. Charged it up to 14.5, and still no change. The battery is new from this january, so I don't believe that's it, and all battery/wire connections were cleaned by the local Ducati dealer 2 months ago.

I'm pretty sure it has to be a condition not being met for the fuel pump to kick on... possibly a bad fuel relay. Going to see about getting a replacement relay to try out this week
 

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Some comments on what you have posted so far and other info.

Obviously the battery needs to be in good condition.

The two major things that affect whether or not the pump will prime is the connection (power) from the run/stop switch getting to the ECU and the side stand up switch or wiring from it working to get the switch closed signal to the ECU.

I have attached a wiring diagram with the important wires coloured and a testing/fault finding guide I wrote some time back.

It seems odd to me that toggling the key and run/stop a few times the let it prime once with short crank time. I.e. there may be a wiring/corroded connection problem in that part of the circuit.

Before delving into testing, I recommend changing the fuses associated with the on/start circuit as per the attached diagram.

The document steps you through what voltages you should see around the circuit.
This is in the doc - A very quick test of the fuel pump is to lift the tank, pull relay 27 (the one closest to the ECU) and use a short piece of wire across the relay socket terminals for pins 30 and 87. This simulates relay 27 closing correctly and this can be done with the bike off, as relay 27 is connected to the battery via a fuse that is not switched. The fuel pump should run.
Also, with the key on and in the run position and the wire bridging 30 and 87, the bike should crank and run.

It seems odd that when it did crank, it was only for a moment - this could the voltage/power to the ECU dropped so low that the ECU turned off - could as before be a fuse issue.

A quick battery test is to turn the bike on and observe the brightness of the headlight. If it dims, then the battery has a problem. Similarly if you measure the voltage at the battery before and during when the headlight is on, if it drops quickly, then the battery has a problem.

The only electrical problem I have had with my bike was corrosion in the connector up from the side/kick stand switch. The made the resistance high and the ECU sensed that the stand was down and hence would not allow the engine to run. I simply cleaned the contacts and use light copper wire wrapped around all three pins to override this input to the ECU.
 

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Discussion Starter #6 (Edited)
Ahhh thanks for the diagram.
I'm betting it's the side stand...
I swapped main and ignition relays and all the instrument lights/headlights came on with either relay... so I don't think it's the relay.

Going to mod the side stand tomorrow

EDIT: So I got restless and removed/bridged the sidestand switch and got nothing... in my frustration, I banged on the starter solonoid, and the starter... and she started up. over and over... think I'm in the market for a new relay
 

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Here is a link to a PDF of that diagram, which is much better resolution than the jpg file I attached.

https://dl.dropboxusercontent.com/u/16291504/900SSie start run diagram.pdf

The all important things are what is happening at relay 27 terminals 85 and 86 as these control the relay coil. Battery positive is to terminal 86 via the stop/run switch and the "energise the coil signal" (going low from the ECU to energise the coil) is to terminal 85.

Bridging 30 and 87 is a great quick test for getting power to the pump and that it runs.

I hope it is as simple as something in the stand up/down circuit.
 

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Discussion Starter #8 (Edited)
Jumped 30 and 87... pump kicked on as it should. Relays are also good.

Picked up a new starter solenoid from the dealer($49 vs $67 online, surprisingly) and installed it. Bike started and ran... so I drove it around the parking lot. Parked it, and she started 3/4 times... Now nothing.

It's gotta be a bad ECU... It's the only other thing that has control over the 27 relay. Side stand circuit is ok, on/off switch is ok, everything else seems to check out. It could explain why the problem is so intermittent, and why it would randomly start or not start.
 

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Key on, in Run position, with relay 27 pulled, are you seeing battery voltage at the socket terminal for 86?

This gets its voltage from the master relay being closed to a fuse (marked injection?) via the red/black to the off/run switch then via the brown wire to pin 86.

The off/run switch also provides voltage to the Start switch. If it does not crank, then you have a problem between the master relay and the output side of the off/run switch.

After that, another thing to try is disconnect the big connector to the ECU and leave it for 10 minutes, then reconnect so the ECU "reboots"
I have seen this with a couple of Japanese bikes and it might work on yours/ours.
 

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After that, another thing to try is disconnect the big connector to the ECU and leave it for 10 minutes, then reconnect so the ECU "reboots"
I have seen this with a couple of Japanese bikes and it might work on yours/ours.
OOPS - I meant disconnect battery negative or positive for 10 minutes, then reconnect.

Make sure / check ECU earth is good/clean as this is the path to battery negative for relay 27 to close when all is good to go.
 

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Discussion Starter #11
Relays are good (Replaced fuel relay, and she started up 8 times in a row, so I took her to the gas station where I ended up getting stuck. after 5 minutes of flicking the on/off switch, she finally started up and I got to go home)

Have side stand connector bridged and working

Terminal 86 in relay 27 has voltage

I'm going to progress with the assumption that the ECU either has a bad ground, or is itself bad(tried resetting it by disconnecting. no change). Will be removing and cleaning all grounds tonight
 

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Cleaning earths certainly will not hurt.

Switch flicking indicates a problem there. Are you flicking the stop/run switch or the key?

Does "jiggling" the wire cluster into the RH switch block make the fuel pump prime. If so, bad connection, corroded wire or switch, broken wire or bad switch.

It is simple to split the switch housing to have a look inside.

If you decide to dismantle the actual switch, do it inside a plastic bag as things can go BOING and disappear forever - i know from experience on another brand where a tiny spring is still hiding somewhere in my shed! Bodged that by using and stretching a spring from inside a relay.
 
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