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Discussion Starter #1
I've got a '16 model Brutale which usually takes at least 2 tries to start when I haven't ridden it for a few days.
This morning it was very stubborn, when it did give a kick, I got the error code- FAULT, PHASE ERROR.

When I did get it running it wouldn't idle and felt like it was only running on two cyls. but all pipes were hot.
or the timing was out (more likely), as it also backfired once.

Could this be a Crank Angle Sensor ?
Is this located at the bottom cam sprocket ?
The bike has 30k on it with no previous problems.
New battery 2 weeks and 500klms ago.

Thanks for any help.
 

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Impressive stable you have there.
Looks like you are about to get the infamous starter sprag failure. If you do a search through this section, I am sure you will find many threads about multiple attempts to start, leading to phase sensor error due to the ecu getting confusing signals about the crank rotation angle.
 

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Discussion Starter #3
Yes, I read those posts, mine turns over just as fast as it always has, but nobody mentioned that their bike ran rough after it started.
Mine won't idle and is all over the place when I turn the throttle.
 

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Does it clear up if you shut it off, key off, and then try again?

The crank angle sensor (crankshaft position sensor - rpm sensor) is in the left engine case cover at the crankshaft.
 

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Discussion Starter #5 (Edited)
The fault clears if the bike is left off for about 10 mins.
No fault showing while the engine is cranking, as soon as it fires the fault shows on the screen.

I was just looking through the manual for the resistance values on the crank angle sensor, can't find the table.
 

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Check the sensor resistance per the manual....and don't forget insulation to ground!!! The manual doesn't mention that, but a short to ground is more common failure mode than a change of resistance. The resistance test won't reveal a short.

I doubt the air gap is changed. Also look closely at the connector to the harness.
 

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I've got a '16 model Brutale which usually takes at least 2 tries to start when I haven't ridden it for a few days.
This morning it was very stubborn, when it did give a kick, I got the error code- FAULT, PHASE ERROR.

When I did get it running it wouldn't idle and felt like it was only running on two cyls. but all pipes were hot.
or the timing was out (more likely), as it also backfired once.

Could this be a Crank Angle Sensor ?
Is this located at the bottom cam sprocket ?
The bike has 30k on it with no previous problems.
New battery 2 weeks and 500klms ago.

Thanks for any help.
ignore that fault code if only appears on start up, its caused by low battery voltage while starting.

Time to change the battery.
 

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I was just looking through the manual for the resistance values on the crank angle sensor, can't find the table.
In the chassis manual:
 

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Discussion Starter #9
ignore that fault code if only appears on start up, its caused by low battery voltage while starting.

Time to change the battery.
In my first post I mentioned that the battery was new and the error appears after the bike has fired up.
 

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It SHOULD be in the engine manual.... at least it shows the VOM with the correct reading, anyway.

Don't forget to check insulation to ground. One meter lead on either wire and the other on the engine case. ANY reading other than infinite is a bad sensor.
 

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Discussion Starter #12 (Edited)
OK, checked the resistance on the sensor, got 656 ohms which is outside the 680 -700 spec,
but better than that shown in the picture in the manual.
I can't imagine such a small degree out would make a difference.

Could be wrong though, it's happened before :p
Just don't want to throw away a couple of hunge for nothing.

No continuity to ground.
Took the new battery back to the shop to get tested, battery ok.

I'm hoping it might just be dry terminals in the sensor plug, so I'll clean them up, put it back together and hope for the best.
 

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Discussion Starter #13
Well that didn't work.

I suppose it could only be the sprag.
Anybody know how much they are in Australia ?
 

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Contact your local mv dealer they can test and if the sprag is faulty some of the costs may be covered by mv Australia. They can put the warranty claim in for you.
 

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Discussion Starter #15 (Edited)
Contact your local mv dealer they can test and if the sprag is faulty some of the costs may be covered by mv Australia. They can put the warranty claim in for you.
The bike's almost 3 years old, I figured warranty would be out of the question.

The other question that's burning me up is, has anyone else who's had the "phase error" caused by sprag issues, had their engine run really rough when it finally does start ? (so rough that it won't idle)
I have to know this or else I'm barking up the wrong tree.
 

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All meter readings are +/- 10%....So you're OK (Only very expensive meters are more accurate).

Your bike will run in a "fail-safe" mode if your ECU is sending a fault code for a sensor that affects ignition and injector timing.

The sprag clutch was a known problem and MV should be helpful with replacement costs if needed, but there is also newer ECU maps that are needed to prevent sprag related problems. If your bike has not been to the dealer in a long time it probably needs the updated latest map.
 

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Discussion Starter #17
Ok, thanks for that, my bike hasn't seen a dealer since I wheeled it out new.
Fail safe mode eh, certainly is ,because I can't ride it.

I'll call a dealer tomorrow to see what the go is, and I'll report back.
Thanks for the help.
 

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Discussion Starter #18
Ok, so spoke to a dealership mech today, who told me that the bike should run fine once it's started.

Looks like I do have some sort of electrical malfunction.
 

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So the next step would be to check the air gap on the phase sensor (crank position sensor, rpm sensor...whatever you call it).

I know of plenty of examples where excessive air gap has caused running problems, but most occur after some other work done in that area...most, not all. It does not take very much.
 

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Discussion Starter #20 (Edited)
Yep, will do.


EDIT: The gap was a bit tight (.5-.55) , so I took a bit of torque off the bolts til I got .65
Tried the starter, but still got the error message.
 
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