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Discussion Starter · #1 ·
The bike in question is an 06 S2R 800, but I believe the same components and wiring are shared among a number of models.

I bought the bike wrecked, and it had been sitting for three years or more. I've been working on it a bit, and picked up a manual on CD.

I had the fuel pump out because the tank had about two gallons of liquid in it, one gallon of which was water! All cleaned out, pump works when connected directly to 12vdc (battery charger). Reassembled and installed, and connected.

I have studied the wiring diagram, but I'm a bit confused. The injector relay brown/white wire appears to be the ground for the relay; that wire has continuity to the brown/white wires at the coils and fuel pump, as it should.

I am trying to figure out which wire is the power for the fuel pump. There are two black wires, which if I understand Ducati's wiring scheme, appear to be grounds. There is the brown/white, which serves as a ground. That only leaves a black/white, which appears to go to the instrument cluster, so I believe that is for the low fuel light.

I can see wires from the ECU to the coils and the injectors, so I can see how the brown/white could be a ground.

But...it doesn't make sense to have three wires at the fuel pump, and three of them grounds.

I have googled "Ducati No Spark" and read many threads. They seem to either point toward the crankshaft position sensor or the fuel pump. I am looking for the CPS and will see where that leads.

But in the mean time, if anyone has experience with the fuel pump and wiring, I would appreciate it.
 

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Ducati usually uses solid black for ground. That brown white should be 12v, directly from the engine management relays. So if it's ground… I think you've found the problem!

Basically, the way it works is one of those black wires goes to the starter relay. When you hit the starter motor, it allows the system to ground and starts spinning the starter motor. However, that's only part of it. There is a 2nd trigger which comes from the ECU, that's the other "black" wire. So the brown/white stays active the moment the ignition is turned on and the black wires control the function using ground.

If you have no spark and no fuel pump, that tells me you have no ignition. Kickstand safety switch, neutral safety switch and clutch lever safety switch are all potential issues. If any one of those isn't working properly, it COULD theoretically cause the ignition system to not work.

I hope that helps a tiny bit…
 

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Discussion Starter · #3 ·
Thank you.
That makes sense, and was what i was trying to say earlier. if brown/white were power, that brown/white wire would supply the fuel pump, coils and the injectors. So now I have to figure out why it's not.

I should have stated earlier that I have isolated the sidestand switch and clutch switch...at least I think I have.

If the kickstand is down, the engine won't turn. Up, it does. In gear, clutch out, no turn. Clutch in, turns. Same with kill switch--off, no turn. On, turns over.
 

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Discussion Starter · #4 ·
Follow up, for those who might be interested:
Not sure why the fuel pump isn't powering, but I think I have found the cause of the no-spark:
When I removed the crank position sensor, it appears to be damaged (cracked, probably impact damage from the crash that brought the bike to me).

Currently trying to find the correct one. The pdfs for the parts manuals available at ProItalia are a great resource, but they show several other Ducatis using the same crank position sensor, when that is just not accurate. For example, they show the same part number for a 996, and the drawing shows it to be the same.

I have a 996 and pulled the CPS--it is smaller in diameter and shorter overall...and the 996 has two mount bolts while the S2R has one.
 

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The crank position sensor also activates the fuel pump. So if it's not working, your fuel pump won't do anything either… So you may have found the problem! EUREKA! :)
 

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Discussion Starter · #6 ·
Thank you again; that is encouraging. Sounds as if I may (finally) be getting somewhere.

I have the sensor on order. A week or so from now, we may have fuel and ignition. :)

Then I will put some money into repairing/replacing the frame, front wheel and rotors. Mirrors, turn signals, bars, etc...

Already have a set of replacement forks...just need to replace the seals.

Gotta love a project bike. Keeps me off the streets...literally. :)
 

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Discussion Starter · #7 ·
Okay, crank position sensor installed, we have spark. :)

However, engine does not fire...unless I shoot some ether into the plug holes. Then it would "bumpa-da-bumpata" a time or two, then just continue cranking without interest.

So, I guess I have a fuel delivery problem. I will investigate.

One other related issue...the first couple times I hit the starter button, the engine would turn over and over and occasionally catch.

After a half dozen tries, the starter would engage, crank for a small portion of a revolution, then disengage.

The starter was not still spinning disengaged or anything like that. Just click-hair-bit-of-turn-nothing. Repeat as required.

One other thing--before I had spark, I had the plugs removed. Hitting the start button caused the starter to engage and crank the engine...even when the button was released, the engine continued to crank until I turned off the key or hit the kill switch.

Al input is welcomed.
 

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That it continues cranking (it does stop eventually, after a minute or less) is by design. It's baked into the ECU firmware. You just touch the switch and automation takes it from there.

When my Monster would not run it turned out the problem was an intermittent break in the hot wire that goes from the fuel pump through the gas tank. The break was actually inside the epoxy plug. Replacing the wiring harness (about $150) seemed the easiest and surest solution.
 

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So… now that you have spark, checking for fuel is actually pretty easy. Simply listen for the fuel pump when you turn on the ignition and if you hear it spin over, with the plugs out, open the throttle body all the way and look through with a flashlight to see if when you hit the starter, you see the spray of fuel. It will tell you right away if your getting fuel into the system. The moment you see it, close the throttle body because it will throw enough fuel in the cylinder to fill it up, which isn't good. Check both cylinders to verify it's getting fuel. If it's not giving you any fuel, but you do hear the pump running, you need to go through more diagnostic procedures. However, if the pump isn't running, then it's electrical diagnosis first.
 

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Discussion Starter · #10 · (Edited)
Gentlemen--
Thank you for the replies.

1. The starter run-on issue is an interesting one, but now that you say it, makes sense.

2. Fuel pump troubleshooting--thank you, I will do as you say. Good idea. I was initially reluctant to crank it without the filter/cover in place, because we all have one or two backfire/burned eyebrows stories, don't we? A friend and I were just exchanging ours a week or so ago. :)

3. I guess I did not emphasize it enough, but the current starter "immediate disengagement" is precluding anything involving cranking until I figure that out. This part:
One other related issue...the first couple times I hit the starter button, the engine would turn over and over and occasionally catch.

After the first half dozen tries, the starter would engage, crank for a small portion of a revolution, then disengage.

The starter was not still spinning disengaged or anything like that. Just click-hair-bit-of-turn-nothing. Repeat as required.
I did some reading on sprag clutch symptoms, but results were inconclusive. I think the other possibility is a shaky solenoid, but he fact is that the onset of this condition was very sudden...no "occasional, then more frequent, then total"...
 

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Yea it does sound like you could have a sprague issue as well. It's an unusual issue on this bike however, so that's why I kinda discounted it. A lot of times low voltage from the battery is the culprit.
 

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Discussion Starter · #12 ·
I'll keep my fingers crossed. I put the battery on the charger yesterday, but it will be a couple days before I get another chance to try again. I am using the battery from my next door neighbor's water craft. Helping him keep it charged through the winter. :)

On the plus side, last time at the Ducati shop I picked up the fuel pump o-ring I had ordered previously, so if I drop the pump (and it sounds as if I will) at least I have a fresh seal.
 
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