Startus interruptus and no tail lights

[Joeker80]

Ok. After following the directions for fixing the startus interruptus problem on my 2014 Norge, my tail lights were not working. Going through the small fuse block near the toolkit storage, I found a 15amp fuse blown. Replaced the fuse, went to start the bike, and it blew again. Is there something I missed about the startus interruptus problem that might be causing this?

[Kiwi Dave]

Due to the initial rush of current when the starter is pressed, I change my fuse for a 20 amp.  Most others do too.

[Joeker80]

So 30 amp fuse from battery to relay and then replace small 15 amp with 20 amp? I’ll give it a shot.

[Kiwi_Roy]

Just what did you do exactly, cut the yellow wire and feed it from another fuse?
When you do this the inrush current is much higher than before (that's why it works better) and a 20 Amp is called for.

Did you make sure the other end of the yellow wire you cut was well insulated, it's still alive.
The tail light is fed separately from the ignition switch as it's also on in the park position.
The original yellow wire should now only draw a fraction of what it once did so shouldn't blow fuses, make sure it's not shorted to chassis.
You can tell by looking at a blown fuse how severe the overload was, a hard short will cause the element to blow with a large gap, a mild overload perhaps just a couple of mm.

[Brian UK]

That fuse originally supplied both the solenoid operating current via the start relays ANd the tail light.
If you have done the startus interruptus mod correctly, that fuse should now only be supplying the tail light. But when you removed the yellow wire from the start realy what did you do with it? If it touches earth anywhere it will always blow the fuse.
You should have added a new inline fuse to the direct feed from the battery to the start relay.

This has nothing to do with the inrush of current through the solenoid, as that fuse in the block should not be feeding the solenoid.
Sick any size fuse you want and if the yellow wire is shorted to earth, it will blow.

[Wayne Orwig]

No idea which 'fix' you installed. I you added a relay I would say maybe you wired it wrong. Can't be sure.

[Joeker80]

I did heat shrink the end of the yellow wire I cut, but perhaps that was not enough. Perhaps putting liquid electrical tape on the end would be better?

For clarification, the yellow wire coming out of the relay socket is now connected to an in-line fuse to the battery. I have not yet tried a 20amp fuse in place of the 15 that keeps blowing. And I have not done anything other than heat shrink the free end of the yellow wire that goes back into the wiring harness.

[Kiwi_Roy]

Does the bike start?
Can you identify which switch is blowing from the following schematic?
http://www.thisoldtractor.com/guzzi007/schematics/2007_Norge_ABS.gif  See Brians post
Your new in line fuse should be 20 Amp but all others should stay as stock.
It's hard finding a short by blowing fuses. If you have an old headlight bulb solder a couple of short wires onto it and stuff them in place of the fuse.
The bulb will supply enough current for most normal loads but if you get a short it will flash at full brightness, it will give you time to figure out exactly what causes the fuse to blow.

[Brian UK]

Roy, that's the wrong wiring diagram. The 2014 model has a different start relay setup with a start relay and a start maintenance relay. Same as the Stelvio.

This begs the question, that yellow wire goes to both relays, which one did you remove it from? It actually links from the first to the second and you need to remove it from both.
If you just removed it from the second start maintenance relay then the start relay is still using the yellow wire, so any problem with the solenoid not pulling in properly would cause that fuse to blow.

When a fuse keeps blowing, it is never the right thing to just put in a larger fuse. Bike have been known to burn doing that.

[Kiwi_Roy]

Thanks Brian
http://www.thisoldtractor.com/guzzi007/schematics/2008_Stelvio.gif
I was almost going to post the 2008 Griso.
http://www.thisoldtractor.com/guzzi007/schematics/2008_Griso_8V.gif
In that case the new fuse should have fed both relays then as though you had clipped the yellow wire where it goes from vertical to horizontal on the diagram.
I'm still not sure why it blew the fuse.
In the case of the double relay I have often said I don't think the maintenance relay is required once you have a strong feed for the start relay, but no-ones ever got back to me to confirm that and I don't have a double relay bike to test it myself.
I believe the maintenance relay was added to fix the weak start relay, it stays energized as long as you hold your finger on the button, the start relay could drop out if the ECU see's low Voltage.
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Either way the signal from the start button goes into the ECU via pin 28 and if all the stars are in alignment comes back out pin 1 to turn on the Start relay.
I would love to see a printout of the logic inside the ECU, it might be as screwed up as the wiring. I spent a good few years working on industrial logic systems.
I'm guessing the ECU monitors the Voltage on pin 17 and if it sees it go too low throws in the towel. Meanwhile the maintenance relay is quite happy to keep the starter engaged
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I'm guessing the inrush to the starter solenoid has gone from ~25 Amps to something like 35 Amps, it will go even higher if the wimpy wire from the relays to the solenoid is upgraded.
The time it takes for the solenoid to engage and start cranking on my early Griso dropped from 50 to 15 milliseconds when I replaced that wire.
The starter solenoid is designed to pull 50 Amps for a split second but the factory insist on strangling it with their spaghetti wiring.
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The start wiring looks complex but it's really quite simple. Of course we don't know exactly what's going on inside the ECU but we do know the signal doesn't get through if the bike is in gear with the stand down and the tip-over (Fall) sensor will also hold it out. A simple sketch might make it a bit clearer.
Note: When the Startup Maintenance Relay closes it disables any of the ECU interlocks, the Maintenance relay will stay closed as long as your finger is on the button.

[Brian UK]

I have a PDF of the Norge GT8 wiring, but can't see a way of uploading it here.

[Kiwi_Roy]

I have a PDF of the Norge GT8 wiring, but can't see a way of uploading it here.

I have found IMGbb if I upload a picture from my camera chip or in this case a scanned sketch from my printer scanner I can then copy and paste the link directly into a post
From the individual pictures (not album) Select Embedded Code option / BBCode/Medium Linked, actually I think most of the options work.
You can organize your images into albums but I haven't discovered yet how to get at the codes from Album view.

[Kiwi Dave]

I have a PDF of the Norge GT8 wiring, but can't see a way of uploading it here.

You can find one (and others) here.

http://www.thisoldtractor.com/moto_guzzi_misc_wiring_diagrams.html

[Brian UK]

Yes, that's the one I have.

[Joeker80]

Ok. In my original post, I stated that the Norge was a 2014. I was having a shit day and got the year mixed up with my Griso. The Norge is actually a 2016. There is only 1 L5A relay with a yellow wire. I clipped that wire and ran a fused connection from the relay to the battery. I have tried to insulate the clipped end of the yellow wire to no avail. The bike just keeps blowing the 15 amp fuse. I even changed it to a 20 amp fuse and it blew that as well. I am really at my wits end here.

[Kiwi_Roy]

It seems as though you have a direct short to ground. cutting the yellow wire didn't cause that.
I don't believe you actually identified the fuse from the wiring diagram, this helps greatly in trying to figure out why the fuse is blowing. It's possible you have a pinched wire
If it doesn't blow immediately you turn the key on can you list the steps you go through before it blows?
Have you tried substituting the fuse with a headlamp bulb, that will supply a normal load but limits the current to < 4 Amps, 8 Amps using both filaments, this works particularly well with an intermittent fault and no fuses are harmed in the process, the light flashes the instant a short occurs letting you identify what causes the short e.g. moving the loom to a certain point.
Another problem we have is the newest schematic available is 2007, do you have a later drawing?

[Brian UK]

Roy, this is the diagram for the Norge GT8, but it's not coloured unfortunately. Think it's a scan from the workshop manual.
https://www.thisoldtractor.com/mg_manuals/wiring_diagram_norge_1200_gt_8v.pdf

It clearly shows two start relays, though they may not now be both the L5A type. 3, the start up relay and 4, the start maintenance relay.

[Kiwi_Roy]

Roy, this is the diagram for the Norge GT8, but it's not coloured unfortunately. Think it's a scan from the workshop manual.
 

Brian,
Thanks for that, I actually prefer the non coloured schematic, besides they do show the wire colours as a letter code.
It shows yet another factory attempt at a Startus Interruptus fix, I will sketch it out and attach. Relays (3) & (4) are different on the drawing, it's possible they are the same in reality. I have no idea why there is a diode shown in relay (6) if you accidentally put the battery in backwards the Main Injection Relay (32) will prevent the ECU from getting power so the Start Relay (3) won't close.

At a glance I would say this should work, at least they now have a strong current to the solenoid even if they have to use the supply from 2 different fuses.
No it won't work, the weak yellow Voltage may be too low to pick up the maintenance relay, same problem the solenoid has . The typical minimum pick-up Voltage of a 12 Volt automotive relay is ~ 6 Volts. The Start relay will always close because the heavy load of the solenoid is not in circuit but it will pull down the Voltage before the maintenance relay has a chance. Nice try Luigi but back to the drawing board i'm afraid
How do you tell if you have this wiring?
See if the Maintenance relay terminal 30 is alive with the key Off, then unplug the Light logic relay, it should go Off
___________________ ___________________ ___________________ ___________________ ___________________
I think I see an easy fix for this wiring, since they use the headlight feed 20 Amp fuse why not feed the start relay direct from that fuse and kill two birds with one stone.
Once running the fuse would revert to operating the lights.
The Maintenance relay may not be required.

[Brian UK]

The fact that there is a diode in that relay means it will not be the same L5A relay as the startup one.

Why Guzzi are making this all so complicated I really don't know. With the simple direct feed in decent gauge wire, and also decent gauge wire from the start relay to the solenoid, my 2 valve Norge starts very reliably, even with a low battery.

[PJPR01]

2008 Norge...have had no issues for years regarding my Startus Interruptus kit from MPH, it's been installed forever, as long as I can remember, practically since new.

Mysteriously now the 15A fuse in the relay of the Startus Int. kit blew.  Nothing has changed on the bike, and I had just ridden it a nice 500 miles a few weekends ago with no problems starting, stopping, running.  Battery all good, and fully charged and reading full voltage.  Decided to charge the battery anyway overnight, fully green...

Put a new 15A fuse in, started right up...went out an hour later, and the fuse is blown again.

What could be the cause I wonder...

[Kiwi_Roy]

2008 Norge...have had no issues for years regarding my Startus Interruptus kit from MPH, it's been installed forever, as long as I can remember, practically since new.

Mysteriously now the 15A fuse in the relay of the Startus Int. kit blew.  Nothing has changed on the bike, and I had just ridden it a nice 500 miles a few weekends ago with no problems starting, stopping, running.  Battery all good, and fully charged and reading full voltage.  Decided to charge the battery anyway overnight, fully green...

Put a new 15A fuse in, started right up...went out an hour later, and the fuse is blown again.

What could be the cause I wonder...

You need to try a 20 Amp fuse, with the MPH fix the inrush current is much higher, more like 40 Amps which is too much for a 15 Amp fuse.
Everyone uses a 20. Check also your battery leads for corrosion, scrape them and coat with vaseline. If the main battery lead is not making good contact a 15 Amp fuse will blow in less than one second because the inrush current (40 Amps) lasts longer.
If you don't use vaseline on the terminals the lead will oxidize, lead oxide is a perfect insulator, it can creep in between the components and isolate the battery, The grease (Vaseline) coats the metal so the nasty Oxygen cannot attack it.
Remember too not all 15 Amp fuses are created equal your original might have been a bit stronger than the last one.

[PJPR01]

Thank you!! That should work well...much appreciated!

[Wayne Orwig]

If the solenoid is a bit dirty and slow, the LARGE current will be there long and pop that 15 amp. I would certainly go with a 20 amp. If that doesn't do it I would clean the solenoid next.

[Brian UK]

When I had problems after doing the wiring mod, I removed the solenoid to find some light brown sticky grease on the plunger. I cleaned it all out, reassembled with a drop of light oil, and it then worked much better. Haven't blown a fuse since.