Series 2 AC brake light problem

[rogscoot]

Hi there, I have an Italian import 1960 Series 2 li150 which is 4 pole Ducati ac without battery.

It was fresh over from Italy a couple of months ago and I've been going through everything trying to get it ready for an MOT so I can register it

This evening I discovered that all the electrics work now excetpt the brake light, the wiring loom I have seems a little strange though and doesn't match up with any in Sticky's book.

Here's a photo of my junction box at the rear, as far as I know everything is ok at the handlebar end:


Please excuse the fuziness!

I seem to have a spare grey wire which if I connect it to anything seems to kill it, ie connect to green it kills the engine, connect to brown it kills the lights.

There also seems to be a spare red wire which is folded back on itself in the main loom, I'm guessing this was there for the scoots with batterys like the UK model but not used on Italian market bikes, would the grey wire be the same?

There was no junction box on the scoot when I bought it, the wires were just taped together, I picked up this junction box second hand and it seems to be the correct type.

I've changed the front and rear bulbs, still running 6v points.

If I disconnect the blue wire and replace it with the grey I don't get any lights but if I press the brake pedal the rear does light up which I guess shows that the brake light switch is at least functioning in some respect.

Does anyone have any ideas? I'm so close to getting it through an MOT now!!

[GeneM]

Red and Grey are usually wires associated with a DC system. Red comes from battery and feeds the Grey circuit. Maybe you have an AC engine and DC harness?

do you have 2 wires at the brake switch?

[rogscoot]

Here's what I have at the brake switch, red and grey going into one connector, I can also see purple wire/s folded back into the loom and another grey wire which has been snipped, is any of this normal for a standard Italian li150?



Also, I managed to pull the red wire out of the loom so now it looks like this:



Would Innocenti have used a DC loom and just hidden the battery wires for non-battery machines?

[Digger]

Your "junction box" looks very much like a recitifier to me..... and your wiring looks identical to that on my TV175 Series III (which is the same as a TV175 Series II) so I'd say you have a DC loom and fittings.

The blue should be taped up and not used.

[rogscoot]

Thanks for the help guys, I had a flash of inspiration at lunchtime and I think I've nailed it....the red and grey connectors go together in one bullet connector and then connect opposite the blue wire, don't ask me why or how, it just seems to work!

Who knows what wiring loom this is but it does look "factory" to me.

Hopefully I can see the summer out on this 6v points setup and then upgrade to 12v electronic over winter!

[GeneM]

That black box looks like a regulator, not a rectifier, probably part of the AC conversion someone has done...

[GeneM]

http://www.scooterhelp.com/electrics/pages/_LI150.2.html

that page shows both AC and DC wiring diagrams

[rogscoot]

Looks like I jumped the gun with thinking I'd fixed it!

Does anyone running a standard 6v series 2 loom have the same red/grey brake switch wiring as mine?

I've checked all the wiring diagrams available and none seem to match what I have!

So frustrating!!

[rogscoot]

BTW It's an Italian market bike so I think should never have had a battery to start with, unless anyone knows otherwise?

[rogscoot]

This is now solved with the help of someone from the Modern Vespa board

For reference it seems that my series 2 had the odd "earth through the brakelight" loom as described here:

http://lambretta.net/lambretta-tech-cen ... parkissues" onclick="window.open(this.href);return false;

You basically won't get it to work with a standard blue/brown/green S2 stator (unless you do some rewiring) so you have to use a stator plate with green/brown/pink (the blue is not used if it exists).

The wires on mine were red rather than pink but the principle is the same.

Thanks,
Rog