Norge 8v electrical failure

[jim mac]

Heading to work this morning and bike starts to stutter and fart all over the place.

ABS warninng light cone on then dashboard lights fail but I can still see the speedo etc. It gets worse and i turn to get it home but it dies.

Sitting at road side trying to get it to start but won't even turn over, first thought is dead battery.

I called out Peter Jones breakdown service to get it home and they sent an AA patrolman who confirmed dead battery bur then said his diagnostic's showed an alternator fault

What are the 'easy' checks for an alternator ha ha ha he laughs to himself hysterically

 

[Raven]

Charge up the battery and get the bike started. If it's anything like a car alternator you should see around 13.8 volts to 14.2 volts with the engine revving slightly. Sounds easy to me.
I think he was pulling your leg with the diagnostics story. What towing company has Moto Guzzi compatible diagnostic equipment on board.
Since it happened suddenly without warning, I'm inclined to think a connection came loose somewhere.

 

[jim mac]

he had a simply electrical circuit tester that showed the charge at 3000 rpm to be 11.4 - hence his side of the road diagnosis that the alternator had a fault. He was from The Automoble Association who are a step or two above your average grease monkey with a tow truck

 

[Raven]

OK I thought the bike was dead, not running. It's hard to do a roadside check of an alternator when the bike is not running.

 

[GTM®]

First and best thing to check once you have a solid/charged battery in place is the belt for condition and tension. The Nippondenso alternator is a solid unit, and the voltage regulator is replaceable for cheap from sources outside of Guzzi... though a rare one.
If the tow driver could in fact read the error codes, non-charging could be anything. My bet is on the belt and/or tension and/or battery itself.

 

[Nick]

Samething happened to me way back. The alt belt was totally shredded.

 

[jim mac]

It has been suggested it might be the Light Logic relay? Now where's that placed ?

 

[kiwi dave]

It's under the seat. Identify which relay it is by the colours of the cables.

 

[Brian UK]

Am I right in thinking that if all the lights are working fine, then the light logic relay is also OK.

 

[canuck1969]

Could be as simple as a blown fuse (assuming you have not thrown a belt). Do a search on Stelvio 30 amp fuse. Believe the 8v Norge has the same wiring logic. I know the relay logic is the same as the 8v stelvio.

Start easy with the 30 amp fuse that supplies the lighting relay power. Then check the fuse that supplies the trigger for that relay. Wiring diagram will be your friend on this one. If both of those fuses are good then check the relay. If you search stelvio loghting logic you will find some information on where to look. The lighting relay supplies exciter power to the alternator. Just need to check the 87a terminal on the relay. If there is power there when the bike is running then the problem will be at the alternator.

Quick test. If there are headlights when the bike is running but not charging it is not fuse or relay related. If there are no headlights when the bike is running then fuse/relay is most likely your issue.

 

[jim mac]

right, got home to a fully charged battery. bike started first push of button, small side lights only . no dipped or full beam, meter reading on battery shows 11.6 i have checked every fuse i can find.

i spotted a wiring diagram on net which showed light logic relay as having 5 wires. the four relays on my bike have four wires each - so whats all that about then, or is the relay hidden up under the tank ?

found it hidden up behind dash on left side. cleaned the connectors, no luck. swapped it for another relay, still no luck

is the fuse hidden somewhere ?

 

[canuck1969]

right, got home to a fully charged battery. bike started first push of button, small side lights only . no dipped or full beam, meter reading on battery shows 11.6 i have checked every fuse i can find.

i spotted a wiring diagram on net which showed light logic relay as having 5 wires. the four relays on my bike have four wires each - so whats all that about then, or is the relay hidden up under the tank ?

found it hidden up behind dash on left side. cleaned the connectors, no luck. swapped it for another relay, still no luck

is the fuse hidden somewhere ?

I am not 100% sure on the Norge where the 30 amp fuse is located but I would start there. Keep in mind, there are 2 30 amp fuses. You want the one that is paired with the 20 amp fuse, not the 40.

If you do not have any lights, then it is not an alternator issue. Means you are not getting power to the lighting relay, or the lighting relay did not trip and you are not getting power to the exciter circuit.

You will need to check for voltage at the relay. You should have 12V to ground (or what ever you battery is reading) at the 30 terminal on the relay. When the bike starts, power from the 30 terminal is moved to terminal 87 and lights the head lights, powers the HB circuit and sends power to the alternator exciter. If you do not have power at the 30 terminal, need to check the fuse. If you have power at 30, but not at 87 then the relay is toast.

I attached the latest wiring diagram in case it is different than what you have.

Also, here is the logic for the lighting relay. The colour will be different, but the terminal numbers will be the same as on your diagram.



Also, if you look through this thread, it will have information on diagnosing the problem. It is for a Stelvio, but the same process can be used.

https://www.guzzitech.com/forums/threads/new-stelvio-arrived.16690/page-2

Report back on the fuse and relay and we can work from there. It will be something simple.

If you want to prove that your alternator is good, run a wire directly from the battery positive to the 87 terminal on the lighting relay when the bike is running. The headlights should come on and the bike should charge.

 

[Wisconsin v7 Racer]

Have you checked the belt like it was suggested or skipped past that? And also just because the battery charged don't rule that out one it was also suggested by Todd.

 

[Brian UK]

If the belt failed I would expect that the charge warning light or similar would have come on, there would have been some indication prior to the battery discharging.

 

[canuck1969]

Have you checked the belt like it was suggested or skipped past that? And also just because the battery charged don't rule that out one it was also suggested by Todd.

Also, if it was the belt or battery issue the headlights and high beams would work. This is a fuse, wiring or a relay issue.

 

[jim mac]

good stuff Canuck, i jumped the 30 and 87 terminals on the relay and got dipped lights and alternator charging at 14.2v. No full beam though ? so i take it that the relay is toasted, got another on order.

15amp fuse for main beam had blown so swapped for new one

 

[canuck1969]

good stuff Canuck, i jumped the 30 and 87 terminals on the relay and got dipped lights and alternator charging at 14.2v. No full beam though ? so i take it that the relay is toasted, got another on order

Excellent. At least you know know it is not the alternator.

It is either the relay, or the relay itself it not being triggered. You need to check the 85 and 86 terminals to make sure they are getting power when the bike starts (review the logic in the previous thread). They both should have power to ground with the bike key on and then one of them should drop power to ground when the bike starts. That is what trips the relay and fires power to 87. If those are doing what they are supposed to, then it is the relay. Sometimes it is just some carbon buildup on the contacts. Can be cleaned but a new relay is best. If you give it a couple of firm wacks while the bike is running it may trigger. Also check to make sure all the connectors on the relay plug are inserted firmly. I chased a problem for 1/2 hr once only to find that the spade connector in the plug was loose.

No full beam is another issue. May be the Highbeam (Full) relay also, but what are the odds of that. From the drawing, it should also be a 5 pin like the Stelvio. It gets power from the 87 terminal on the lighting relay. In its normal state, 87a on the HB relay sends power to the dipped lights. When you flip the switch, it triggers the HB relay and then power switches from 87a to 87 and dipps turn off, and fulls come on. Again, if you jump 30 and 87 on the HB relay, they should come on (just don't do it for long as dip and full will come on at the same time). If it does not come on, either the relay is not working or 86 and 85 are not getting the signal to trip (this is assuming there is power from the 87 terminal of the lighting relay to terminal 30 on the HB relay)

Here is the logic of the HB relay for the Stelvio. Wire colours will be different, but the logic will be the same for each terminal. 85 and 86 may be flipped around but makes no difference.

 

[canuck1969]

good stuff Canuck, i jumped the 30 and 87 terminals on the relay and got dipped lights and alternator charging at 14.2v. No full beam though ? so i take it that the relay is toasted, got another on order

Just one clarification. You jumped between 30 and 87, or you jumped from the battery to 30 and the battery to 87?

 

[Brian UK]

I'm fairly sure the 15A fuse replaced is fuse A which will disable the whole lighting and charging system if blown. Jumping across the light logic relay will bring on the dip beam, but not main beam as the dip/main relay is energised from fuse A, as of course is the light logic relay.
Thus no replacement relay is required.

 

[canuck1969]

I'm fairly sure the 15A fuse replaced is fuse A which will disable the whole lighting and charging system if blown. Jumping across the light logic relay will bring on the dip beam, but not main beam as the dip/main relay is energised from fuse A, as of course is the light logic relay.
Thus no replacement relay is required.

I totally missed the last line of the post about the 15 amp fuse, but that is correct.

Did the High beams work when the fuse was replaced??

That was why I asked to look at the 85 and 86 trigger terminals for power. If there is no power there, neither of the relays will trip when needed.

The 30 to 87 jumper was just to rule out the alternator as being an issue and prove power at terminal 30.

Hopefully it is just a fuse. Of course, why the fuse blew is always a mystery. There is a lot on that 15 amp fuse so the adventure may not be over yet.