m o t trouble

[mattrick]

husqvarna 50cc.just failed mot because indecators are affecting another lamp,any ideas what would cause this.checked over wiring but cant work out where the problem is.could a faulty indecator relay switch cause this to happen.any ideas most welcome.thanks.

[Guest]

an earth plugged in the wrong connector..

[Guest]

its an earth fault. If The indicators are making your tail light to dim check the earth return from the tail light and the two rear indicators. It will just be a corroded or chafed connector.

[mattrick]

thanks guys.electrics isnt my thing,so at the risk of sounding stupid can you tell me which wire is the earth.there are three wires going into the light, two plug in towards the bottom of the tail light bulb and the other plugs in towards the side.is the one on the side the earth.???

[Guest]

this is most likely.. you will have a + for rear light, a + for brake light and a shared earth -.

check the connectors with the indicators, is it one side? check that side, disconnect the connectors (bullets) and connect to the opposite one, ie AA and BB change to AB and BA.. if you get where i'm coming from (still on the same side, undo both and swap which goes to which)

and try the indicator/ check the light, i take it that then rear light is effected?? otherwise check the front connections..

normally wires are colour coded, so black plugs into black, and black/white into black/white etc, etc..

[mattrick]

thanks i get what you are saying and will check it out.

[Guest]

another one who needs to invest in a digital volt meter !

[mattrick]

i bought a volt meter and couldnt work out how to use it.i know serious lack of brain cells,call it a miss spent youth on the funny fags.theyll let anyone on the road these days.give me a spanner or ratchet any day of the week and im fine.electrics make my head hurt.

[Guest]

i still work off a wire with a bulb, or a bulb screwdriver, tells me what i want to know, in simple terms, power and earth...

[mattrick]

a bulb screwdrier is a bit more up my alley'

thanks for the help.

[Colin the Bear]

You're just looking for continuity of the circuit. The positive side of the battery is connected via the main fuse , the harness and switch gear to the various electrical application on the vehicle. The negative side is connected at various points to the frame for the return run. This is the earth on a DC system.

If the return (earth) is interrupted at any point it will take the path of least resistance, which can be through another application. This can be seen when the tail light flashes dimly with a dim indicator when the indicator is operated.

Positive (power) is getting through but can't find it's way back and is having to come the long way.

Clean all the contacts in the bulb housing and open, clean and reconnect all connectors.

Put your meter on low resistance or continuity and check for a route home.

In your tail light, the bulb has two filaments, one for tail light and one for brake light. They use a common return(earth) hence the three wires. The earth wire goes from the bulb to the housing or the frame.

The return(earth) fault would appear to be on the indicators. You don't say if it is one or both. I'd be looking at the connectors, first.

[mattrick]

thanks.