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Discussion Starter #201
There is a "load shedding relay" on that bike which cuts power to everything else when the start button in depressed so that the starter gets full power through the start solenoid - which is also just a switch or relay.
Interesting, I'll keep that in mind. I'm just gonna go top down from the Haynes electrical checks list, I have 4 or so different tools to check this crap. I thought about PERHAPS if I can get one, buying another Harness just to have and examine. I'm probably going to upbolt the bracket with the coils, and get the airbox out of the way fully before I move on.

I really hoped to get the bike started before I go to New Zealand....lord KNOWS if I rebuilt the carbs correctly. But regardless....I understand how most of this part of the bike goes together so I can get back into the carbs MUCH easier this time....sometime...........................................in the future.
 

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Yeah! I have done the test in the Haynes for the ignition and I got dick.

I have positive power at the starter solonoid....and then I have none at number 85 socket on the on the general relay socket,.and I have none on the backside of fuse block for the main 30 amp fuse.

I've pulled the general relay and applied juice to it from a drill bat, and can hear it click.

Unless something is fucked inside the ignition barell, otherwise it seems that and it's associated white plug are good to go.

None of the harness is degraded beyond what we may think for its age. Nothing is frayed..all the various tubing and heat shrink look great so I don't THINK it's a short.

Some are still the old style. But I mean...I'm.not even getting positive power TO the fuse block yet.

Can a busted starter solonoid hijack all the just for the bike?

No comment is unappreciated!

Based on very limited knowledge and so little to go on hahah...I expect the new battery to show same result because I mean....it's not a limping circuit...this bitch is d e a d

Sent from my SM-G950U using Tapatalk
I dont know if you said anything about the 30 amp main fuse or not--Did you check this fusible link yet??
 

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Gonna get that checked out tonight if I can find it :)
under starboard fairing panel--positioned basically behind the turn signal--rectangular black plastic box-aprox 1 1/2 inches long maybe 1 inch high-hinged on the top-so squeeze the bottom side of the lid and it should open right up--it's mounted to the fairing support bracket
 

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Discussion Starter #206 (Edited)
Ok so a nice little update, was able to go down today and fart around.

Good news, ignition continuity check seems ok.....I see numbers on my meter bouncing around on the correct closed link when it's turned to ON / Off / ETC, so the switch seems ok, that's nice I didn't want to figure out those security bolts.

The Fusable link is in good condish as well, thanks for pointing that one out Rennsportmotorrad.

Starter Solonoid, unknown. I didn't do the testing for it, I don't have a spare battery around or a bunch of wire leads to set up the test., but if looks count for anything (they don't) it's in GREAT CONDISH. The connectors look really good and clean and protected by booties, the white connector seems fine as well.

Next up was some regulator testing, and although the haynes manual is a bit cryptic (no pictures for this, NOOOOOOO), I tried to pull "full battery voltage with ignition turned to "ON" from every combination of the 3 wires I could and never got shit. This is from the connectors coming out of the harness, into the regulator. So I guess that is bad, Haynes says to "check the wiring to the alternator, battery, etc" which leaves me a bit cold. I only have 3 regulator wires, 2 are red/black, 1 is red/white.

Onward and upward....I guess I can continuity check those wires if I can find out where they come out of the harness. But we're getting somewhere I think? She's still D E A D without so much of a whimper out of the 12.5 volts she's hooked up to......I wonder if there is a hidden positive wire I've totally not connected up. Now that I know some of these things are working fine, and overall the connectors look great, and haynes has led me to "check the wires".........I'm more nervous than ever.

Shouldn't I be able to get full battery voltage at that Fusable Link? Now that I've been in there a bit more, I realize that man, it sure does seem like I don't have that positive lead split that sends power here, which seems impossible

"Hello Motogadget................."
 

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also dont dismiss the possibility that in a multi pin connector that maybe one of the connectors is broken or not making contact---Not that you dont have enough to make your head explode already lol
 

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Keep looking you will find it--then you will slap you head and say WTF because you have looked at that 50 times already lol
 

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I mean no offense, but you seem even more lost around electrical problems than I am ! 😁
I’ll tell you some things that help : Get some alligator clips and make two jumpers about 3 ‘ long with a clip on each end. Use these to make sure you’re getting 12v + from the battery to test solenoid, starter etc. Voltage should really be around 13.2 on a good battery wth no loss to the solenoid.
You should load test the battery. They will do it for you at the parts store if you don’t have a load tester.
Always clean both ends of your ground wires, and their contact points, to bare metal. Don’t forget the one by the brake pedal. I recommend a “single source ground” where you run a wire from each ground point to the main battery ground on the frame.
If you have the stock main hot wire from the battery, check that you’re getting 12v to the solenoid and that 12v tap in the middle that supplies the rest of the bike is ok.
It sounds as if you are not comfortable checking this stuff. You’ll get more familiar with it as you go.
 

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The main relay is a switch. It has what is called switching power to activate it, as well as a ground. That takes up two terminals. The other two terminals, opposite one another are the switched terminals.

One should have 12V of battery power. This is called waiting power. When the switching power is turned on (you, turning on the ignition) the relay should then close, and waiting power is then supplied across the switch. The terminal that was unpowered, is now powered and should provide power to the rest of the bike.

The starter relay works in the same manner. It should receive its switching power from the ignition switch which should get its power from the main relay. Waiting power should also be direct from the battery.

With your test light, probe the relay for those terminals with power. Then directly across from that terminal, see if that terminal gets power when you turn on the ignition switch. If you don't, and the relay clicks, you have a fault relay.

Just to be clear, find the terminal that has power with everything off. If you then switch the key switch to on, the opposite terminal should power up. That should pass power to the rest of the bike. Report back to us when you get that far.

I could refer you to the schematic but I get the feeling that would just overly complicate my description for you.....sean
 

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No offense mate. Battery is load tested, what do you mean "12v tap in the middle"

My advice would be to admit defeat as far as the electrical loom is concerned, you can get a competent mobile mechanic to come and check it, likely fix anything or advise if new parts are needed in an hour, what would that cost? $50?

Do that to get yourself past this hurdle as it's pretty obvious you're struggling with it, which is nothing to be ashamed of, if you watch the tech work i will almost guarantee the whole lot will be so obvious to you once he's diagnosed it....
 

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Stop... go slow. It worked before you touched it so carefully back track everything you touched and even if you are 100% sure it is right double check it. Even us pro's make mistakes and need to remember that on occasions. The answer is right in front of you and making it more complex by heading into new areas first just muddies the water, start with a slow back tracking of everything you have done to this point and document all connections.

Simplify everything and start with a wiring schematic and a power flow chart of the circuit you are working on, follow the power to where you are losing it. Figure out where you have power and figure out where you have grounds. test them and then move on to the next. these bikes have reliable harnesses so it is usually a owner hooking something up backwards or not connected that causes a problem. A reversed battery can blow a rectifier or fuse in a second but often this only effects charging. Back to the beginning of where is power lost, follow electricity like water.
where is the leak?
where is the clog?

Pm sent
 

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Discussion Starter #216 (Edited)
With your test light, probe the relay for those terminals with power. Then directly across from that terminal, see if that terminal gets power when you turn on the ignition switch. If you don't, and the relay clicks, you have a fault relay.

Just to be clear, find the terminal that has power with everything off. If you then switch the key switch to on, the opposite terminal should power up. That should pass power to the rest of the bike. Report back to us when you get that far.

I could refer you to the schematic but I get the feeling that would just overly complicate my description for you.....sean
I've bench tested the relay and it does click, I need to double check the relay sockets and see that they are, or are not, getting power. The diagram makes perfect sense, there are some "splits" that are not indicated by anything but a "dot" so I'm unsure where this takes place, maybe its' a split that's happening under a huge piece of shrink tubing within the loom. Regardless, I should be able to test for continuity through the loom with my meter.

I appreciate everyone's help tremendously, but don't get more frustrated than me, and don't get frustrated for me. I do complex VFX for my job and there is no way in hell a mid 90s "analog" Ducatis wiring is harder to figure out than the VFX for something like The Avengers or Star Wars, and strangers pay me money to do that crap.

I have other bikes, I bought this one to do exactly this. And I also had to unfuck a spedometer cable that "professionals" did on my 01 748s, so I'm not all in on the pros sometimes.

I did go a bit crazy testing shit, but as I said, sometimes I can only go down and work on the bike for 20 minutes. I can easily test some things, some things take a bit more time than I currently seem to have! And every test teaches me something, ignition circuit seems to be fine, the white box regulator thing bench tests with a click, I'm missing the little resistor thing on the positive from Bat but i've read that some people bypass that and cable upgrades for our bikes don't have it. And I believe that I'm not getting positive power to the main regulator thing. All of this is about 1.5 hours of my time, including going down there and setting up a bit.

Hang with me guys!!!!!! Are we a bunch of "take it to a pro" pussies or are we DUCATI OWNERS!!! I promise that there are special little gifts for everyone who helps me on the horizon. Are we part of team Save the SuperSports OR NOT!!!!!!
 

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Did the new battery show up yet??? I didnt see if you said it had or not
 

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I thought maybe this might help you a bit with visualizing what the relay is supposed to do. Yes, I know you bench tested it, and it clicked. All that means is, the electromagnet part worked the switch.


You can see the schematic on the relay above. It is pretty typical for a vast number of relays available. 35 and 36 are the electromagnetic part while 30 and 37 are the switch. One of those #37s should have power from the battery. The other, should get power when the relay is activated in the manner I wrote about before.

If you can picture that with regard to the socket it plugs into, then you should be able to determine which one has power to it, and if the other gets that power when you switch the key switch on. The starter relay should be wired similarly. A couple of more images to maybe help convey what I'm trying to explain:

Disregard all the labels but this is what you should see on the bottom. You'll find dozens of pics on the web of this as this type relay is used in a zillion different applications. Hope this is of some help.....sean
 

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No offense mate. Battery is load tested, what do you mean "12v tap in the middle"
Why would your ignorance offend me ? 😁If you have the stock positive cable there is a block in the middle of it where the electrical system connects for everything else on the bike that requires 12v power. It causes a reduction in the amount of power to the solenoid. The aftermarket cable kits don’t have this, allowing full voltage to the solenoid. If you replace this cable, make a pigtail from your positive battery terminal to supply current to the things that were connected there.
 

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Although @Iwannaduc diagram is more descript for this particular application, if you're wondering what all those relay numbers mean, here is a generic list:

 
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