Need help with ignition switch wiring – Ducati 350, 1973, Electronic Ignition)

[Klaus]

Schaltplan 250, 350, 450 elettrico.jpeg

Lightswitsch 5 Pins.jpeg

Light Switsch 5 Pins.jpeg

CEV 169 oben.jpeg

I am looking for advice on how to correctly wire this switch for a Ducati 350, 1973, equipped with electronic ignition and the standard 3-fuse setup.
Technical details of the switch:
The switch features a single input pole on one side and four pins on the opposite side. The switching logic is as follows:
Position 1: Double-arm contact connects Pin 1 and 2.
Position 2: Contact between Pin 2 and 3.
Position 3: Contact between Pin 3 and 4.
Requirement: It must be possible to turn on the parking lights while the ignition is switched off.
This unit works in conjunction with a CEV 169 handlebar switch, which manages the high/low beams, indicators, and the horn. Unfortunately, I am struggling to interpret the original Ducati wiring diagram correctly and could use some guidance on which wire goes where.
Best regards from Wetzlar, Germany!

I am not sure, but the original light switch has 8 Pins.

Best regards from Wetzlar, Germany"

[veloduke]

This is what I would do (others may disagree ).

So, looking at the first picture of the switch;

The tab on its own should have black and yellow connected (connecting to 20,21 and 7)

Then left to right across the bottom of the switch;
Black/white (to fuse)
Red (to 19 handlebar switch)
White (to 15, side light)
Red (to fuse)

So switch turned left to give parking lights and instrument lights
Switch centre position to give no lights
Switch turned right to give main lights, rear light and instrument lights

A couple of observations;

Fuses 17 and 18 are shown connected at the fuse box. I think this is a mistake, as the are connected at the ignition switch, and this would put them in parallel. Protection to the lighting cicuits would be compromised. For example if the parking light developed a short, then the main lights fuse would blow too. Also, you would be able to activate the main lights with the ignition turned off.

With the switch set for parking, the instrument lights would be on. Maybe not desired. Moving the black wires (to 20 and 21) to join the red wire (to 19) would allow the instrument lights to come on only when the main lights are activated.

Hope this helps

[Klaus]

Hi Max,
please excuse my late reply. I had a nasty accident with my road bike and will continue the Ducati project in the autumn.

Best regards
Klaus

[Duccout]

Hi Klaus,

I am so sorry to hear about your accident. How are you? Get well soon.

Kind Regards,

Colin

[veloduke]

Wow, sorry to hear that Klaus. I hope you weren't hurt.

[Roland]

Gute Besserung!

I used the the same schematic to make a new wiring for my scrambler.
I did some modifications, as explained by Max, everything works well.

So it took some time to find the mentioned mistake, here it is corrected: