[McBob]

Hello,

I was thinking of replacing my Euro 4 C5 right hand switch module with an Euro 3 module, to be able to switch off the headlight.

Actually, this is just an excuse for tinkering with the bike. I'm sure you can relate to that.

Anyway, this is not a plug-and-play operation. According to several YouTube videos you also have to do some rewiring inside
the casquette. I see it done either professionally, building a contraption with connectors and everything else to put between
existing connectors (just as some of us did with the homemade booster plug), or more quickly and messily, pulling out wires
from existing connectors and... well, re-connecting them together in a different way.

I hope I am being sufficiently clear. I have tried purchasing (well, enquiring about purchasing) the contraption, which is
purportedly for sale, with no answer from the interested party, and so I wonder: does anyone out there have
already made something similar with some schematics to share, so I can build the contraption myself? I am ready
to pay a reasonable fee.

Either that, or we could discuss and come to a solution together. Thanks a lot,

Rob

EDIT: I've seen that Minda produces, actually, a plug-and-play switch module. I would still be able to make an
AHO wire by myself, to use with an Euro 3 stock switch module. Bear with me.

[richard211]

It's a very simple conversion. To try and simplify what needs to be done, all one would need to do is direct the head light power feed from the Left hand main harness connector to the Euro 3 Right Hand headlight switch and bring the switched headlight power output to the power input terminal of the headlight high / low beam switch. If needed, I could do a write up on it.

[Haggis]

Only two bits of wire.
And a euro 3 switch of course.
You do need to be able to remove the terminals from the block connector and crimp the same type of terminal onto your new wire.

[McBob]

Only two bits of wire.
And a euro 3 switch of course.
You do need to be able to remove the terminals from the block connector and crimp the same type of terminal onto your new wire.

Hi Haggis, is that an image of the same conversion decribed by richard211? Thanks a lot (to both).

[Haggis]

Yep, sounds the same as richard211.
The feed that did go to your high/low switch has to now go to the new lights on/off switch.
The return from the new switch then goes to the hi/low switch.

[McBob]

Ok. Now I've been able to study both the Euro 3 and the Euro 4 wiring diagrams on the Haynes manual with different eyes.

Thanks to both of you I have a clear idea (and the right tools) of what is to be done.

But, there is also the stock wiring harness to take care of! Now I see why the YouTube contraption had four connectors.

I think, now, I should be able to draw a diagram for the contraption, purchase the necessary wires and connectors, and crimp away! Let's see what happens.

Thanks again, that was invaluable.

[CHURCHILL]

https://www.motone.co.uk/triumph-bonneville-c25/h4-headlight-module-battery-saver-safe-start-p2028


I have one of these fitted on my Enfield Trials 500 inbetween the bulb and the connector block, Motone sell them for Triumph and Enfield and I have one on mt Bonnie 865 also, no other mods required and can be removed in a few moments

[MannP]

Can you advise if the use of the Euro 3 switch with rewiring allows the rear light to also be turned off with main front light by using the switch, or does it only control the front light?

Thanks

[Haggis]

The switch operates all lights.
First position,  P,  turns on tail light, front position lamp and both tiger eyes.
Second position, H, turns on headlight as well.
Off position turn off all lights.

[MannP]

Thanks Haggis, so with the wiring described the euro3 switch on euro4 will act as a euro3 setup, I like that!!

[Haggis]

Yep, that's what I have done on both my bikes.

[MannP]

Just a thought, does the 'passing light' flick switch on the top of the LH switch gear work in this conversion with the lights switched off?.

[Haggis]

Yes.🏴󠁧󠁢󠁳󠁣󠁴󠁿

[MannP]

I am just about to do this conversion, l have the Euro 3 switch in place but am getting a bit wobbly with the wiring.

The new red plug on the Euro 3 switch is a 9 pin plug with 8 wires in it, the existing receiving plug in the loom is a red 9 pin with four wires in it.

I understand from the diagram on the thread here that i will be making two new connections into the existing receiving plug meaning it will have 6 wires, but what about the other two wires in the new Euro 3 plug? they will go to nothing, are they no needed?

Thanks

[Haggis]

There is also the wire for the tiger eyes.
They are crimped together on the bike side of the connector.  You need to separate them and fit them into the connector block. I'll try and take a photo tomorrow.