Author Topic: V50 Mk2 wiring - help needed  (Read 631 times)

Offline injundave

  • Guzzi Mentor
  • ****
  • *
  • *
  • *
  • *
  • Posts: 353
  • Location: Havelock North, New Zealand
V50 Mk2 wiring - help needed
« on: December 09, 2018, 09:22:47 PM »
In the process of going through my V50 for my daughter I discovered that the original Lego-type switch has passed its use-by date. I have bought another switch which has everything I want i.e. Lights On-Off, Hi/Low beam, horn and turn signals but it has far fewer wires (8) in comparison to the original (13).

I am struggling to work out which to connect where, The diagram for the new switch is:




The original wiring diagram is:




Can any of you wiring gurus advise how to connect the two to get everything working, please?

Thanks to Greg Bender for the V50 wiring diagram.
« Last Edit: December 09, 2018, 09:40:36 PM by injundave »
1975 850 T3
1980 V50
1988 V65 Lario

Online Antietam Classic Cycle

  • Guzzi Hero
  • *****
  • *
  • *
  • Posts: 9390
  • Happily stuck in the past.
    • Antietam Classic Cycle
  • Location: Rohrersville, Maryland
Re: V50 Mk2 wiring - help needed
« Reply #1 on: December 09, 2018, 09:26:05 PM »
What brand of switch is the new one? Photo?

Charlie
http://www.AntietamClassicCycle.com
'69 V700
'69 Ambassador
'76 Convert
'85 Moto Morini 350 K2


Offline injundave

  • Guzzi Mentor
  • ****
  • *
  • *
  • *
  • *
  • Posts: 353
  • Location: Havelock North, New Zealand
Re: V50 Mk2 wiring - help needed
« Reply #2 on: December 09, 2018, 10:24:20 PM »
Its one I bought from Ali Express. The bottom carries the legend "domino Made in Italy.



« Last Edit: December 09, 2018, 10:41:42 PM by injundave »
1975 850 T3
1980 V50
1988 V65 Lario

Online Kiwi_Roy

  • Guzzi Hero
  • *****
  • *
  • Posts: 6919
Re: V50 Mk2 wiring - help needed
« Reply #3 on: December 10, 2018, 02:36:22 AM »
Your new switch seems to have most of the functions of the old one but I don't see the function OFF/Park/ON
Of course it would be plug and play if you had an original switch

I think the yellow wire goes to the light master switch and it then jumpers internally to the H/L red button, check that with your meter.

Start by doing one function at a time e.g. Indication, headlight, Horn/Flash
If you have the mating part of the Molex connector don't put the pins in until you have tried it first

Don't feel bad about not being able to figure it out, I'm having trouble too
 

Molex Connector (loom side)                              New Switch Wire
Pin
1  Light fuse F3                                                 Yellow
2  No connection this is between the headlight On/Off old dimmer switch, it doesn't go anywhere.
3  Ground for Horn and Flash buttons                 
Green this was wrong green should not go to 3
4  Hot for Park & Tail lights Fuse F4         I don't think this needs to be through the switch, Jumper to 7
5  Headlight Low Beam                                       Black     
6  Headlight High Beam                                      White                   
7  Park Light & Tail Lights                       I don't think this needs to be through the switch, Jumper to 4
8  Turn Signal Left                                              Red
9  Turn Signal Right                                            Blue
10 Headlight Flash Relay                                     Blue/White
11 Horn                                                             Grey
12 Turn Signal Flasher relay                                Blue/Black

Work in progress
« Last Edit: December 13, 2018, 05:40:22 PM by Kiwi_Roy »
72 Eldorado
07 Griso 1100
17 V7iii Special

Moto Guzzi - making electricians out of riders since 1921

Offline Murray

  • Guzzi Hero
  • *****
  • Posts: 2472
Re: V50 Mk2 wiring - help needed
« Reply #4 on: December 10, 2018, 03:57:10 AM »
What does the new switch block do for earths? back through the handlebar? I'll Have a further look when I get a chance.

We may need more info or you need to bell out the new switch on the original switch gear the power for the overtaking lights and headlights is routed separately on the new switch this doesn't appear to be the case. Upon further examination, the horn and it appears the flash overtaking is earth switched meaning the switch completes the earth circuit on the original switch gear pin 3 is dedicated to this earth, there appears to be no dedicated pin on the new switch gear although its possible it relies on a contact to the handle bar for this purpose. The headlights on the original switch gear however appear to be power switched meaning you would need a 12volt feed in and a wire out to go to the relevant circuit not sure if the new switch gear uses the power in for flash for this purpose.

The new switch gear may assume (quiet sensibly) that for high current circuits it is switching relays rather than direct power which appears to be the case from the diagram, the number key might be nice. It looks like relay 24 is for the flash circuit but doesn't run the headlights and there is no headlight relay, sense it makes none, however Italian electrics have a reputation for a reason. Now it is entirely possible I'm missing a joint in the diagram. Might be time to sit down and write out a few diagrams and work out whats what where, actual electrical work is typically pretty quick and easy, its the figuring it out that takes the time, the opposite to mechanics IMO.
« Last Edit: December 10, 2018, 07:35:23 AM by Murray »

Online Moto

  • Guzzi Hero
  • *****
  • *
  • *
  • *
  • Posts: 3045
  • pazzi per la Moto Guzzi
  • Location: Madison, WI
Re: V50 Mk2 wiring - help needed
« Reply #5 on: December 10, 2018, 07:50:08 AM »
Its one I bought from Ali Express. The bottom carries the legend "domino Made in Italy.





Your switch appears to be a version of the OEM switch on my Griso:





I recommend you BUY ANOTHER SWITCH. The reason is that the horn and turn signal positions are reversed from the usual positions on these switches. If you install yours you will doom yourself to a lifetime of blowing the horn when you want to cancel the turn signals, and canceling the turn signals when you want to blow the horn. This has been a constant source of complaints from Griso owners ever since the bike was introduced. I consider it to be pretty dangerous, and started to install another switch, though I haven't completed the project yet.

[EDIT: Rereading your first post, I see it is to be your daughter's bike. She could be expected to get used to the button positions if it is her first bike, and then be set up for carrying the reflexes she develops to all regular bikes she may later ride. Just as bad.]

The switch I bought for my project is this one from MG Cycle:





(http://www.mgcycle.com/index.php?main_page=product_info&cPath=37_140&products_id=183).

If you decide to buy this one, I can provide information on its internal wiring, which I had to determine by testing. It seems to be a well-made switch.

I repeat, BACK AWAY FROM THE SWITCH.

Moto




« Last Edit: December 10, 2018, 07:55:39 AM by Moto »
1976 850-T3
2007 GRiSO 1100
2017 Italjet/SSR Buccaneer 250i

Online Kiwi_Roy

  • Guzzi Hero
  • *****
  • *
  • Posts: 6919
Re: V50 Mk2 wiring - help needed
« Reply #6 on: December 10, 2018, 09:55:49 AM »
Taking note of what Moto says, it could be an issue, I just adapted to my Griso, it didn't take long.
I never even realized they were backwards from normal, I had an Eldorado, VII Sport, a Lario and California II at the time.
I had to remember the gearshift was 1 Down 4 Up instead of 1 Up and 4 down as well, no big deal.
72 Eldorado
07 Griso 1100
17 V7iii Special

Moto Guzzi - making electricians out of riders since 1921

Online Moto

  • Guzzi Hero
  • *****
  • *
  • *
  • *
  • Posts: 3045
  • pazzi per la Moto Guzzi
  • Location: Madison, WI
Re: V50 Mk2 wiring - help needed
« Reply #7 on: December 10, 2018, 10:15:09 AM »
Taking note of what Moto says, it could be an issue, I just adapted to my Griso, it didn't take long.
I never even realized they were backwards from normal, I had an Eldorado, VII Sport, a Lario and California II at the time.
I had to remember the gearshift was 1 Down 4 Up instead of 1 Up and 4 down as well, no big deal.

Yes, I could be less adaptable than some. I do have other bikes I ride that have the buttons in the right places.

In case you decide to proceed with the switch you've got, you might take the Griso's switch diagram as a possible model for your own mapping efforts. It has more wires exiting the switch, and performs more functions, but if yours is actually from the same company, as I suspect, it may have similarities in its internals. Here is the Griso switch's diagram:





Once you digest the format, this diagram is an excellent statement of the functionality. I recommend starting with a similar grid and filling it in for the switch you've got.

But I really recommend getting another switch for the sake of your daughter.

M.
1976 850-T3
2007 GRiSO 1100
2017 Italjet/SSR Buccaneer 250i

Online Kiwi_Roy

  • Guzzi Hero
  • *****
  • *
  • Posts: 6919
Re: V50 Mk2 wiring - help needed
« Reply #8 on: December 10, 2018, 10:36:15 AM »
Moto,
         Again, I can't fault your thinking but perhaps if she gets used to this switch then buy her a Griso



Murray,
           I wondered about the ground for the horn and Headlight flash as well, I think its the Green wire and can be used as either ground or +12 Volts depending on how the bike is wired, it would be easy to check with a multimeter to the Blue/White or Grey wires with the appropriate button pushed.
« Last Edit: December 10, 2018, 10:54:55 AM by Kiwi_Roy »
72 Eldorado
07 Griso 1100
17 V7iii Special

Moto Guzzi - making electricians out of riders since 1921

Online Moto

  • Guzzi Hero
  • *****
  • *
  • *
  • *
  • Posts: 3045
  • pazzi per la Moto Guzzi
  • Location: Madison, WI
Re: V50 Mk2 wiring - help needed
« Reply #9 on: December 10, 2018, 11:47:20 AM »
Again, I can't fault your thinking but perhaps if she gets used to this switch then buy her a Griso

 :rolleyes:
1976 850-T3
2007 GRiSO 1100
2017 Italjet/SSR Buccaneer 250i

Online Chuck in Indiana

  • Guzzi Hero
  • *****
  • *
  • *
  • *
  • *
  • *
  • Posts: 25584
Re: V50 Mk2 wiring - help needed
« Reply #10 on: December 10, 2018, 03:02:48 PM »
I'm with Moto on this one. I *hate* having a non standard switch. I use the horn maybe twice a year, but when I do, I want it to be the HORN, not the turnsignal.. what were they thinking?
Chuck in (Elwood) Indiana/sometimes SoCal

02 Scura RC
87 AeroLario
79 G5
95 Skorpion tour
 
The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt.' - Bertrand Russell

Offline Murray

  • Guzzi Hero
  • *****
  • Posts: 2472
Re: V50 Mk2 wiring - help needed
« Reply #11 on: December 10, 2018, 04:05:51 PM »


Murray,
           I wondered about the ground for the horn and Headlight flash as well, I think its the Green wire and can be used as either ground or +12 Volts depending on how the bike is wired, it would be easy to check with a multimeter to the Blue/White or Grey wires with the appropriate button pushed.

That's possible however what is the scheme for the headlight on the new switch vs the original V50 wiring, does it expect power from the same wire?

Online Kiwi_Roy

  • Guzzi Hero
  • *****
  • *
  • Posts: 6919
Re: V50 Mk2 wiring - help needed
« Reply #12 on: December 10, 2018, 04:55:00 PM »
That's possible however what is the scheme for the headlight on the new switch vs the original V50 wiring, does it expect power from the same wire?
I thought the headlight feed was the yellow wire, I think it feeds the light switch, from the other side of switch to the common of the H/L selector.
Easy to tell with an Ohmmeter on Black & White, does it connect to Yellow with the switch On?

All this talk about switch compatibility, What was the original V50?

The only thing the young Lady will notice is how nice it is to use after this.
« Last Edit: December 10, 2018, 05:31:37 PM by Kiwi_Roy »
72 Eldorado
07 Griso 1100
17 V7iii Special

Moto Guzzi - making electricians out of riders since 1921

Offline Guido Valvole

  • Guzzi Hero
  • *****
  • Posts: 1148
Re: V50 Mk2 wiring - help needed
« Reply #13 on: December 11, 2018, 12:40:00 PM »
When the two tiny strands of copper in the original left-side switch on my V50 II gave up the ghost I replaced it with the one in Moto's illustration. More copper, more electrons, brighter headlight! (also did headlight relay and H4 conversion, now I can see where I'm going). It wasn't plug and play, but wasn't too bad. Taillight is on all the time now, though. Not necessarily bad. Connectors are standard Molex, readily available from any good electronics store or online.

When the starter switch on my Monza (V50 III) died for the same reason, I replaced it with the Domino/Tomaselli one. And used that as an excuse to upgrade to a Tomaselli quarter-turn throttle. A little fiddling with cables but much better than stock. Or you can just cut the switch part of the unit and use the stock throttle assembly (cheap Guzzi content). HOWEVER that's a V50 III. Not plug and play on a II. There are lots of little and not so little differences between the two. V50II switch is flakey but still in use as I didn't quite figure out the proper wiring for the Domino one.
V50 II
V50 Monza
Le Mans 1000 (IV)
Martinez, CA

Offline injundave

  • Guzzi Mentor
  • ****
  • *
  • *
  • *
  • *
  • Posts: 353
  • Location: Havelock North, New Zealand
Re: V50 Mk2 wiring - help needed
« Reply #14 on: December 13, 2018, 01:03:38 PM »
Thank you for all your interest. I had already worked out some of the connections and took Kiwi Roy's guide to work out the rest. Everything went well until I connected terminal 1 to Yellow. Everything was fine until I switched on the key and the plastic on the yellow wire melted. Hmmmmmmm, back to the drawing board.

After all that I found a diagram on the Gutsibits website which tells me all I need to know. If I can work out how to put up a PDF on here I will post it.



Dave
« Last Edit: December 13, 2018, 01:30:30 PM by injundave »
1975 850 T3
1980 V50
1988 V65 Lario

Online Kiwi_Roy

  • Guzzi Hero
  • *****
  • *
  • Posts: 6919
Re: V50 Mk2 wiring - help needed
« Reply #15 on: December 13, 2018, 01:25:31 PM »
You must have a short to chassis on the yellow wire or one of the other headlight wires Black or White\What size fuse do you have feeding terminal 1, shows a red/black wire at the fuse block, I think
72 Eldorado
07 Griso 1100
17 V7iii Special

Moto Guzzi - making electricians out of riders since 1921

Offline injundave

  • Guzzi Mentor
  • ****
  • *
  • *
  • *
  • *
  • Posts: 353
  • Location: Havelock North, New Zealand
Re: V50 Mk2 wiring - help needed
« Reply #16 on: December 13, 2018, 01:33:50 PM »
15 amp and yes, red/white. According to the new diagram green on the new switch is the common feed to the horn, flasher and headlight. Yellow is the park light.
1975 850 T3
1980 V50
1988 V65 Lario

Online Kiwi_Roy

  • Guzzi Hero
  • *****
  • *
  • Posts: 6919
Re: V50 Mk2 wiring - help needed
« Reply #17 on: December 13, 2018, 02:12:15 PM »
15 amp and yes, red/white. According to the new diagram green on the new switch is the common feed to the horn, flasher and headlight. Yellow is the park light.

New Diagram?  post No 1said Headlight.
(I assume it's a smaller wire to lose it's magic smoke with just a 15 Amp fuse
Still shouldn't have shorted.

Please Ohm it out and find what other wires it connects to in the different switch positions.
Does the switch make ground contact with the bars?
72 Eldorado
07 Griso 1100
17 V7iii Special

Moto Guzzi - making electricians out of riders since 1921

Offline injundave

  • Guzzi Mentor
  • ****
  • *
  • *
  • *
  • *
  • Posts: 353
  • Location: Havelock North, New Zealand
Re: V50 Mk2 wiring - help needed
« Reply #18 on: December 13, 2018, 02:20:46 PM »
It would appear that the switch has melted internally as the headlight switch no longer works. I cannot say if it earths through the bars but I will pull it apart and have a look.
1975 850 T3
1980 V50
1988 V65 Lario

Online Kiwi_Roy

  • Guzzi Hero
  • *****
  • *
  • Posts: 6919
Re: V50 Mk2 wiring - help needed
« Reply #19 on: December 13, 2018, 02:57:57 PM »
Are you sure the fuse didn't pop. it should have before any damage was done otherwise it's not doing its job.

Please post the new diagram.
72 Eldorado
07 Griso 1100
17 V7iii Special

Moto Guzzi - making electricians out of riders since 1921

Offline injundave

  • Guzzi Mentor
  • ****
  • *
  • *
  • *
  • *
  • Posts: 353
  • Location: Havelock North, New Zealand
Re: V50 Mk2 wiring - help needed
« Reply #20 on: December 13, 2018, 03:42:30 PM »
The fuse definitely did not pop. As suspected part of the switch has melted. I already have a new one coming.





« Last Edit: December 13, 2018, 03:45:04 PM by injundave »
1975 850 T3
1980 V50
1988 V65 Lario

Online Kiwi_Roy

  • Guzzi Hero
  • *****
  • *
  • Posts: 6919
Re: V50 Mk2 wiring - help needed
« Reply #21 on: December 13, 2018, 05:36:16 PM »
Yes, it appears I told you to put the green wire in the wrong place. The new diagram shows it clearly.

I'm sorry about that.

Pin 3 of the Molex connector is grounded on another connector 17

I suggest replacing the fuses with 5 Amp while you check it out, they will have less capacity to do any further damage.
« Last Edit: December 13, 2018, 05:45:17 PM by Kiwi_Roy »
72 Eldorado
07 Griso 1100
17 V7iii Special

Moto Guzzi - making electricians out of riders since 1921

Offline injundave

  • Guzzi Mentor
  • ****
  • *
  • *
  • *
  • *
  • Posts: 353
  • Location: Havelock North, New Zealand
Re: V50 Mk2 wiring - help needed
« Reply #22 on: December 13, 2018, 07:35:40 PM »
I think the 5 amp fuse suggestion is a good one, which I will do for testing. The switch has no earth through the bars.

Thanks for all your help.

Dave
1975 850 T3
1980 V50
1988 V65 Lario

Offline Diploman

  • "The future just ain't what it used to be." Yogi
  • Guzzi Mentor
  • ****
  • Posts: 428
  • Location: Murrysville PA
Re: V50 Mk2 wiring - help needed
« Reply #23 on: December 14, 2018, 11:03:18 PM »
Given that you need new switch in any case, you could use this reproduction V50 switch from MG Cycle.  It should have the same functions and same wire format as the original - might be plug-and -play.  It would also be period-correct.  I have the original OE switch on my V50II and it works very well, once you get accustomed to the rather unusual layout of buttons and functions compared to modern switchgear.  One useful function on the V50 OE or Repro switch no longer available on modern switches is the headlight shutoff position:  the bike can be started with headlight off, using full battery power.  In any event using a V50 repro switch would be significantly simpler than adapting a modern switch with a totally different wiring scheme to your bike's OE electrical system.

http://www.mgcycle.com/index.php?main_page=product_info&cPath=37_140&products_id=4352
« Last Edit: December 14, 2018, 11:10:00 PM by Diploman »
1980 V50 II, lightly cafe'd, much modernized
1983 SP 1000 NT (Under Upgrade/Modification)
2015 KTM 390 Duke

Online Antietam Classic Cycle

  • Guzzi Hero
  • *****
  • *
  • *
  • Posts: 9390
  • Happily stuck in the past.
    • Antietam Classic Cycle
  • Location: Rohrersville, Maryland
Re: V50 Mk2 wiring - help needed
« Reply #24 on: December 15, 2018, 09:02:02 AM »
The K&S 12-0030 switch has a headlight on/off switch. I've put them on a V65 (same wiring cross as detailed here: http://thisoldtractor.com/moto_guzzi_tonti_handlebar_switch_-_k_s_12-0030_fitment_to_a_moto_guzzi_california_ii.html) and numerous Tonti and Loops.
Charlie
http://www.AntietamClassicCycle.com
'69 V700
'69 Ambassador
'76 Convert
'85 Moto Morini 350 K2

 

20 Ounce Stainless Steel Double Insulated Tumbler with donation credit
Buy a quality tumbler and support the forum at the same time!
Better than a YETI! BPA and Lead free.
Advertise Here