headlight goes on and off & other stuff

[DaveTomo]

Having a few issues,looking for some pointers please where to start - 12v AC
1) 1st one has been like it for 12 months or so,hasn't really bothered me too much but I am wondering whether its all related .If I don't have the lights on when I press the brake pedal the speedo light goes on.
2) Headlight is flickering on and off ( I don't mean tickover flickering) especially when you rev it it goes on and off, checked the connections at the back of the bulb holder all seem OK.If a regulator was breaking down would it show these symptoms or is it a case of it either works or it doesn't.
Any help or advice gratefully received.

[Nelly]

Dave,
I don't think the 2 are related.
I think the first one is a wiring issue, something is not where it's supposed to be. It's one of those I would need to test with the multimeter, not something I can diagnose here.
The second could be a regulator issue, it may only be regulating one half of the AC waveform. Try another regulator and take it from there.
Test with a multimeter at the bulb to see what voltage you get (AC setting) and test at the output of the regulator (don't disconnect the loom) to see if you get the same voltage.
Sorry I can't be any more help here.

[Chadley]

1) I would suspect this to be a poor earth on your rear lamp. Without a proper earth, when the brake light is on the current will feed through the brake light filament and then the rear light filament (that you wouldn't notice) to the speedo bulb before finding a path to ground.

2) Don't know but could again be due to a dodgy earth, this time from the headlamp bulb.

[DaveTomo]

Thankyou chaps appreciate the advice,gives me something to go at,thankyou

[Jazzy b]

I've just had a similar prob on one of my scoots it was a faulty rear light changed and sorted

[Shaun]

1) 1st one has been like it for 12 months or so,hasn't really bothered me too much but I am wondering whether its all related .If I don't have the lights on when I press the brake pedal the speedo light goes on.

Probs not what I am going to suggest, but..............
We get the odd car failure on MOT similar to this.
When we drive them in we always look at the dash as we press the brake pedal.
Once in a blue moon as we press the brake pedal the dash and all position lights illuminate.
This is down to a single filament bulb in a twin filament bulb holder, therefore brake light power feeds straight through to position lights, and position lights swtched on also lights the brake lights (not as easy to spot from the riding/driving position).
And don't be fooled by thinking its impossible to mix bulbs, some twin filaments only have one foot.

As I say, most likely not this, but I would have a peek out of curiosity.

Shaun.

[DaveTomo]

Bit of an update, found what's causing the flickering lights.Checked all the connections again CDI , regulator, tried a new regulator, different bulb holder.No different, got the multi meter on the stator all readings OK, looked at the light switch seemed OK...........rigged up an old light switch temporarily, lights stopped flickering on and off Had a closer look at the light switch fitted to the scoot - orange wire was in but loose,quick flick with a small screwdriver and out it popped, basically a dry joint so when it was being revved the orange wire was rattling around (blue wire doesn't look clever either)


Anyway a bit of solder and it should be sorted.Haven't done the backlight/speedo bulb mystery yet but will be fitting a BGM LED rear light over the weekend so hopefully that will get it done.Appreciate all your feedback,thankyou