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New Stelvio arrived

20170121 141430
OK back to it. Here are the results for the lighting relay. Sorry for the image rotation, and the tape used to edit errors. The voltage drop at 87a probably isn't significant I'd guess. So this means it isn't charging?
 
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Your status with just the key on is correct. You are getting power in the correct places and you have power at 30 which means power from the 30 amp fuse.

With your engine running, the trigger is firing (86 going to zero) but the fact that 30 goes to zero makes no sense what so ever if it had power with the key off. That basically means that power from the 30 amp fuse is now gone when you start the bike. There is no way that I can see that actually happening as the power that supplies the 30 amp fuse and terminal 30 comes directly from the battery.

I went out and tried different scenarios to get power on terminal 30 with the key on and no power with the bike running. I pulled the 30 amp fuse and it looses power to terminal 30 (which it should). I then went back one more step to the 40 amp fuse which is the fuse for the generator which also supplies power to the 30 amp fuse. Basically power is split between the battery and the generator for the 30 amp fuse. When I pull the 40 power is killed the 30 with key on. That means that there is no way to loose power to the 30 amp fuse as it is directly feed from the battery. As long as you have power at the battery you have power at the 40 amp fuse and therefore you have power at the 30 amp and then at terminal 30 on the lighting relay. Actually, that power circuit happens whether the key is on or off as it is a direct battery feed. There is no mechanism that I can find that will cut power to that circuit when the bike is running.

Verify a few things.

1. Now that you have registered no power at the lighting relay terminal 30 (white/green wire) with the bike running, is there still power there right now with the key on or off.
2. What brand and model number is the relay. Just want to confirm there is not something weird with that relay.
3. Pull the startup maintenance relay and confirm that it is one that has a diode on the trigger. It should have a drawing on it. It should look like this. The triangle with the line is the diode.

Upload 2017 1 21 22 14 35

4. I honestly can't see how the power would be dropped to that circuit on startup. Only other possibility I can think of is the ignition switch but I can't see where in schematic it could happen. That being said, the drawing may not be right. When it is running, give it a couple of hits and jiggle the wires. Not exactly scientific but may uncover something.

If anyone else wants to chime in please do so, as at this moment I am completely stumped.
 
OK, I found a path that could give the scenario you have.

If the maintenance relay is stuck in the closed position, or it is a relay that does not have a diode, it can back feed power to the 30 terminal on the lighting relay through the 87a terminal which in turn back feed power to the 30 amp and so on. In other words it can give the illusion of power on the 30 amp circuit with the key on. When the bike starts the lighting relay flips from 87a to 87 and looses the back feed. There may indeed be no power on that 30 amp circuit. It would mean two failures (30 amp circuit and maintenance relay but it is possible as both of those items have failed before).

Pull the maintenance relay and then double check that 30 amp fuse again and then also check the 40 amp. Do a continuity test on the fuse to make sure they are working. Make sure you have power to ground on both sides of the fuses with them installed. Key on or off should not make a difference with the maintenance relay pulled as you have removed the potential back feed. Alternately, if you pull the maintenance relay, do you still have power at the 30 terminal on the lighting relay with the key on. If you don't then that is your problem, along with some blown fuses.

Only scenario I can see.
 
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OK, I found a path that could give the scenario you have.

If the maintenance relay is stuck in the closed position, or it is a relay that does not have a diode, it can back feed power to the 30 terminal on the lighting relay through the 87a terminal which in turn back feed power to the 30 amp and so on. In other words it can give the illusion of power on the 30 amp circuit with the key on. When the bike starts the lighting relay flips from 87a to 87 and looses the back feed. There may indeed be no power on that 30 amp circuit. It would mean two failures (30 amp circuit and maintenance relay but it is possible as both of those items have failed before).

Pull the maintenance relay and then double check that 30 amp fuse again and then also check the 40 amp. Do a continuity test on the fuse to make sure they are working. Make sure you have power to ground on both sides of the fuses with them installed. Key on or off should not make a difference with the maintenance relay pulled as you have removed the potential back feed. Alternately, if you pull the maintenance relay, do you still have power at the 30 terminal on the lighting relay with the key on. If you don't then that is your problem, along with some blown fuses.

Only scenario I can see.
 
It occurred to me later that the dead 30 pin on the lighting relay when running was, well impossible, but explains the symptoms. I was tempted to just jumper a 12v supply to that pin from the battery but figured it would be best to disconnect its current lead but wasn't sure that could be done short of snipping the wire. At any rate when I can start it up and not disturb the early Sunday morning quiett I will do the checks you suggest.

The relays I bought were NAPA Echilin, always top notch in my opinion but tried the original too with the same result.
 
You don't need to start the bike. For now just check the 40amp fuse next to the battery negative terminal (and re check the 30 amp) to make sure they are good. Key on or off should. It make any difference as they r both direct feeds from the battery. Don't just do a visual. Check them using your meter in continuity mode to be sure. If they are both good then we know there is something else. No idea what at this time but without the diagnostics you will just be shooting in the dark.

Did u also replace the maintenance relay with a new one. That one is special since it has a diode. Different than all the rest.
 
The 30 and 40 amp fuses are good. I reconfirmed this with continuity check. I did not replace the maintenance relay but it is the proper one with the diode symbol, and I even gave it a few taps if it was stuck, but no dice. What is the test for that relay? This sure is weird.
 
Wow. Pretty much all I can say.

If both the fuses are good then u need to verify power is getting to the lighting relay.

Pull the Maintenace relay for these test. With the key off test the power on both sides of the 30 amp fuse to ground. You should be able to get a probe on the fuse spades. Makes sure u test both sides. It should read 12 v

Replace the maintenance relay and then do the same test as above with the bike running. Should still read power. If it does not then we know we have a problem further up.

Lastly do a continuity check with the bike off from both sides of the fuse with it in place to terminal 30 on the lighting relay (white /green wire) This will tell us if the wire is broken.

Once we confirm the above we can look at the maintenance relay.
 
Well this is my bad. I was certain that I had confirmed power to the 30A fuse. (that being the rear side fuse in the rear two fuse block, under the triangle cover.) However I now find that it is dead. Who knows, senior moment.

Lighting relay post 30 is of course as I said hot,when not running. The back feed thing? So I guess that's it? I simply have to find out why it isn't getting any power to the 30 fuse block position. Which takes us back to the initial diagnosis of a blown fuse. In which case I've wasted some of your and others time. Sorry. Offhand do you know of where connectors might be that supply it?
 
Was it dead on both sides of the fuse?

Do the same power test to the 40 amp fuse on the holder under the negative lead. This supplies power to the 30 amp. Check both sides of the fuse with the key off. Do u have power to ground there on both sides. That line is directly connected to the battery positive lead. Not 100% where is all goes. Just need to follow the wires.

For the 30 amp fuse. Is it the one that is paired with the 20 amp. Post a picture if you can.
 
Yes checked both sides of the 30, and had today again confirmed that the 40 was hot and it is. I don't think any need for a picture, it's the one that is shown in the manual as the rear one of the two, the 20 being forward. Leads are green/white and red/green.
 
OK, getting closer to the problem. Check the same thing on the 40 amp then we will know where to go from there. Sounding like a broken wire somewhere as that 40 amp fuse pretty much goes directly to the positive lead on the battery. Slowly narrowing it down which is good news. Don't let the maintenance relay or the power on terminal 30 throw you. Since there is a diode in that maintenance relay, and there is no power flowing the other way from the 30 or 40 amp fuse then it may be completely normal. Start on the power side as everything starts there.

Pretty sure those splices are in the wiring harness so will not be easy to find. All depends on if you have any power around the 40 amp fuse. I believe both join the harness behind the triangular panel. Hoping it is an obvious break. If not, may mean having to undo wrap the harness.

Lets see what you get from the 40 amp fuse on both sides then we can figure out where to go from there. Good news is you are getting closer. This one is a new one on me. Don't think I have heard of an internal splice letting go but I can see how it could happen if someone was not careful with the soldering.

Upload 2017 1 22 18 25 46





Let me know when you get a chance.
 
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OK, and to be clear the 40a was hot and the fuse good by continuity check. What I don't get is why the lighting relay 30 terminal is hot with the switch on if the 30 a fuse which supplies it isn't. As I said I was sure I had checked that the 30a fuse block was hot but maybe I was just assuming it was because that lighting relay 30 terminal was.
 
I don't have an explaination as to why terminal 30 was hot. Only thing I can think of was the back feed from the maintenance relay. Did u pull the maintenance relay. Pull it out and see if the power drops out with the key on. There is no other power source for the lighting relay. If the 30 amp is dead so is power to the relay.

If you now have power at the 40 amp and no power at the 30 amp and the fuse is good you have a wire break between the 30 and 40. Those splices are in the actual wiring harness. You can see the buldges in the harness behind the triangular panel where they both join the harness. You can start to peel back the harness to look for it but I think u will probably do more harm than good. Your choice on this one. I can be done if you are careful but work area is tight in there.

If I was u I would run a brand new 30 amp fused feed from the battery directly to the white/green wire on the 30 amp fuse. This is a direct line to the relay. I would leave the existing fuse in place in case that splice decides to become live again.

Look for obvious rub spots in the harness. Maybe you will find something. It should have blown a fuse but maybe it was a quick break. Also look at the 30 amp fuse holder. Perhaps the red/green wire is loose. Did u check for power at the wire or the fuse. If the fuse, check for power to ground at the wire. Perhaps the fuse holder is broken.

Don't see any other solutions for u at this time. You can just do a quick test with a wire jam bed into the bottom of the fuse from the battery. Will tell you very quickly if the solution will work if the lights come on and u are charging.

There is a small possibility that the break on the wire is before the charging system meets with that circuit. It shouldn't be as you don't have any power at the 30 amp but I would confirm that. When you do the test above if the lights come on when the bike is running but no charge then you have a much larger problem.
 
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Well I feel so damn incompetent because this evening I checked the 30a fuse block one more time and now it's hot. I poked probed and prodded the hell out of it yesterday trying to make sure I was making contact and even hauled out my Harbor Freight meter instead of using my Sunpro. As I said I was certain I had checked it before and it was good. Go figure.

Lighting relay post 30 is only hot when the 30a fuse is in. Which is correct of course, which leaves me, in limbo. It isn't the fuses or relays it seems. The lights should work even if the alternator isn't working, right? Oh, and I am sure I mentioned, way back, that the driving lights don't work. Probably not relevant but...

Should I try a direct battery connection to the lighting relay 30 and see if the damn thing charges and lights then. Remember it goes cold when running. Of course it makes no sense.

Replace the maintenance relay , just because? I am lost what part that one plays.

Again, I am not in any particular hurry. i'm working big hours and this old man has little energy left for this stuff, especially in my cold dim garage. Truth be told my patience working on my own vehicles has been approaching zero for several yeas and luckily haven't needed much. Then too, electrical, well as I say I don't believe in electricity. My eyes glaze over looking at electrical schematics. Pneumatic, hydraulics I get. Mechanical prints, right at home. Give me some warm bright spring days and am sure I will be energized. Oh, and I am retiring in late May.
 
Are both sides of the fuse hot when the bike is running???

Driving lights are all part of that circuit. Turn them off and try again. They are know to short and blow the 30 amp fuse. As strange as everything else that is happening on your bike, I am wondering if they are shorted in a way to divert power from the relay. There is no way that can possibly happen but just go out then and turn off your aux lights at the grip switch. Then start the bike again. You bike is already possessed so anything is possible.

Failing that my friend I have no other solutions for you. By now you know the lay of the land and how everything is supposed to work. The lights should still come on if the lighting relay has power even if the bike is not charging. If you are going to run a new wire I would just run it from the battery to the white/green on the fuse block. Will be a shorter and easier run. Just make sure you fuse the wire with a 30 amp fuse as it leaves the battery as to minimize the un-fused length. As a test, you can try it without the fuse. It will tell you very quickly what is happening. My guess is everything will work. If it doesn't well hell if I know at this point.
 
What is the part number for the Echlin relays that you purchased. I don't see a cross reference to the Bosch 5 Pin Relay. Lets eliminate the obvious that the relays you have put in there are indeed the correct ones. Only other thing that makes sense is the terminal configuration is different or they gave you a relay with a diode.
 
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