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Discussion Starter #1
Where can I find a wiring diagram specific to this year/model? I have one downloaded from the main tech page here, but my wires don't seem to match up. I'm referring to the Brutale 800 ABS. I'm trying to see if I have a pinched or broken wire going to/from the throttle assembly.

Thank you!

Keith
 

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Discussion Starter #2
I have zero patients lately. To me the ECU end of the harness feels as though many sockets don't have metal contacts in them. I'm using a staple on a clip to test for conductivity, so not to spread the socket wider than it already was, but many sockets feel like they are 3x the size of others in the same row, and I can not get a reading on my Fluke meter.

So...... I decided it would be an easy endeavor to take the harness out and bring it to my electronics shop at work. That's a more difficult task than I had bargained for. I broke the connector that mounts to the ABS unit. I can't figure out how to snake the harness out without taking the frame apart. What the F am I doing to my beautiful new bike with 600 miles on it!!!! The gas position alarm was happening every time I rode it, sometimes 4 or 5 times in an hour.

I am seriously thinking of parting it out now. I don't want to go to a dealer and get handed a $3,000 bill for a new harness and the labor that it took to undo the damage I'm already doing. I'm so frustrated with myself. This is nothing like fixing a dirt bike.

Thank you for letting me vent.
 

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These bikes are complicated can-bus electrical machines. Just tearing into a harness without some sort of previous experience and knowledge can get expensive quickly.

Now that you have vented, and I am less than 30 minutes from you, would you like some help tackling your issue?

I am not a certified mechanic, but I play one on TV...:smoking:
 
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Discussion Starter #4
Thank you SS!

I may very well take you up on the offer. I took the weekend away from the bike. Tonight I will focus on tracing the 7 throttle unit wires again. I swear that some of the socket locations that are supposed to have a socket inside them are empty.

Here is what I am looking for, according to page E7 and E8 of the -b3-675-800-dragster-workshop-manual from the wonderful catalog kept by @Donsy. If this manual is not the correct one, then that could be my issue. I would hope they would use the same harness for a 2016 B3 800 RR as older 800 ABS models.


I am looking at position/connector 21 which should be the Throttle Potentiometer and following it to the ORANGE ECU connector. I am using staples attached to clips with a Fluke multimeter, trying to verify conductivity with resistance at 0 ohms.

B4 to GREY wire

J4 to BROWN wire

K1 to Org/Blue wire

E2 to the SKY BLUE wire

C1 to the Orange/Violet wire

E4 to the Brown/Grey wire

C2 to the Blue/Black wire


Am I on the right track?
 

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Discussion Starter #5
I peeled the PVC jacket on the throttle end of the harness back to the main harness to look for a break or a crush
no issues. Here is what I found with my Fluke meter set to ohms

Pin 1 to K1 has conductivity to 0.1 ohms

Pin 2 to B4 has no conductivity

Pin 3 to J4 has conductivity to 0.1 ohms

Pin 4 is empty

Pin 5 to E2 has no conductivity

Pin 6 to C1 has no conductivity

Pin 7 to E4 has no conductivity AND the ECU socket is empty

Pin 8 to C2 has conductivity to 0.1 ohms

I checked pins 2, 5, 6 and 7 to every socket on the orange/red ECU connector. No conductivity whatsoever.

I checked pins 2, 5, 6 and 7 to each other for a short. No conductivity.

I checked socket B4, E2, C1 and E4 (even though it's empty) for shorts. No conductivity whatsoever either.

Does this seem normal that I could have 4 bad wires?
 

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Discussion Starter #6
The 4 wires that weren't conducting actually go to the BLACK ECU connector. The wiring diagram didn't show them going to 2 different connectors. But, it's a big relief. I bent, tugged and twisted each wire to see if there were any instantaneous or intermittent disruptions to the resistance. All is good. Time to wrap up the cable jacket that I opened up and put all of the harness connections back together. I also have to figure out how to put the battery box back into it's place. I'm done for the night. I really can't wait to be able to ride it without worrying, just like I was able to do.for the 1st 24 hours that I owned it. The GAS POSITION warning didn't come in until after I read about the potential. Lol. Do I have munchausen syndrome?? Lol

Could a dead battery have caused any of this heartache? My service appointment is still scheduled for the 10th of August.
 

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Low voltage cause much heartache with the MVs. There is a low voltage cutoff in the ECU that stops everything and shuts the bike down.

The GAS POSITION warning is a well known foible with fixes stated in other threads.
 

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Discussion Starter #8
The GAS POSITION warning is a well known foible with fixes stated in other threads.
The very first thing I did was to clean and dielectric grease the throttle harness connector and both ECU harness connectors. This seemed to make things worse meaning the error occurred more frequently. Maybe I over did the grease? Before I took ownership of the bike, it sat for some time with either a dead battery or no battery at all. Is that a clue? Hopefully by the weekend I will have things buttoned up and see if the error still exists. I did notice that the error only appears when idling. It never happened while on the throttle. How difficult is it to get to the other end of the battery cables?
 

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To get to the battery, you have to pull the fuel tank.

I would pull the main fuse and let it sit for a bit, then reinstall the fuse.

Sometimes that resets all issues.
 

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Discussion Starter #10
I have the battery out. If I wanted to inspect the connections at the other end of the battery cables, is that a good size job? I haven't looked at it.
 

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@Knewman_03703: Would you please put your bike's model and year in your signature line so that I don't have to go find it each time!

Or, you could post the model and year in every post you make. Help us help you.
 

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Discussion Starter #13
@silentservice703: Thank you for your help and guidance She's all back together after finding no issues with the wiring harness, and the gas position error still exists. I'm trailering her to Cycles 128 tomorrow for the 1st service AND for the error code. Hopefully they can sort it out while I'm away on vacation. I know they don't know me from Adam, but I hope they at least try to sneak this 2 year old bike with 600 miles on it through MV warranty.

My question to you is do you know if they would flash the ECU as part of the 1st service?


I can't wait to gain some trust in this bike.
 

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Ask them to verify the ECU programming. I suspect Gido will do that anyway, but it always helps to lay your cards on the table.
 

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Discussion Starter #15
Got the bike back from Cycles 128 a week ago. Finally took it out for a proper ride this weekend. New Hampshire was having a mini-bike rally in Laconia. Put 600 miles on it over 3 days. The bike is flawless. The power is everything I had hoped it would be. The handling is way more capable than I am. The sound is intoxicating! Other than the seat, the bike is very comfortable to ride. I am very happy with the service at this dealer. They changed the RBW throttle assembly and the Sprague clutch, both under warranty. While it was there they also did the 1st service seeing it had almost 700 miles on it.

She's a keeper!
 
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