Irritating little s@*t

No, I'm not referring to Pikey.

I have a problem with one of my rear lights on my Defender.

When I put the side lights on, it works OK.

When I brake, the brake lights come on.

But when the side lights are on and I brake, both lights go out.

I understand that typically this signifies an earthing problem, but as it's a common earth with all the rear lights I doubt if it's an earth to chassis grounding issue. Because both lights have a single common earth problem, it's unlikely to be a broken cable.

So far I've replaced the bulb; replaced the bulb holder; checked the tightness of the connectors into the plug which the bulb holder connects to. I am now at a loss as to what else it could be. I've considered replacing the connector which the bulb holder connects up to, but can't find anybody who sells them, having tried the obvious; Craddocks; Paddocks; Simmonites; VWP etc.

Any ideas?

poor earth either bulb holder/connector pins or wire ,complete light units are cheap

have you the right type bulb

jamesmartin said:

poor earth either bulb holder/connector pins or wire ,complete light units are cheap

Click to expand...

I've replaced the bulb holder twice, just in case the first one was faulty. I suppose both could be dodgy (Britpart), but I can't help wonder if it could be the male connector, but I can't find a supplier.

Spunka said:

have you the right type bulb

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Yep. Also tried swapping with RH and works OK

i dont know about recent one but the britpart light were as good as any though all can be poor with contacts in holder and connector pins ,one of those jobs that can take hours , i often use stc4637 link lead as a replacement as its easier than just changing connector
https://www.google.co.uk/url?sa=t&r...1w7YWlXIrN1kZR0ug&sig2=nEEp5n32h374zufz1ef5FA

ps and holder amr1422

dont know wots wrong but you are supplying the bulb with two feeds which cancel each other out the same way your alt light goes out when it starts chargeing
earth fault

Very common problem. I ran separate earths back to chassis. Job done. But check the bulbs have the correct offset pins and you are not bodging the wrong one in.

jamesmartin said:

i dont know about recent one but the britpart light were as good as any though all can be poor with contacts in holder and connector pins ,one of those jobs that can take hours , i often use stc4637 link lead as a replacement as its easier than just changing connector
https://www.google.co.uk/url?sa=t&r...1w7YWlXIrN1kZR0ug&sig2=nEEp5n32h374zufz1ef5FA

ps and holder amr1422

Click to expand...

Thanks, 2 connectors & holders ordered.

See, if you were on that 106 pug forum you would have been still waiting in anticipation for suggestions or an answer to your plea

True, but if I owned a Pug I'm not sure a dodgy light would be my problem.

yep busted common earth.
filament 1 earth's via filament 2 and vice versa
when both filaments are energised there is no potential difference so no
current flow and neither lights up.

but the simple answer is as always lucas!

The usual cause of this problem is the electrical contact between the body of the bulb and the the inside of the bulb holder, nothing to do with the spring contacts at the bottom of the builb holder.

Check that it's all clean and shiny and a fairly tight fit before you start delving into the wiring.

brian47 said:

The usual cause of this problem is the electrical contact between the body of the bulb and the the inside of the bulb holder, nothing to do with the spring contacts at the bottom of the builb holder.

Check that it's all clean and shiny and a fairly tight fit before you start delving into the wiring.

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Thanks, that will be the copper contact then. I'll have a look tomorrow and see whether there is an obvious problem, although I have tried 2 bulbs and 2 bulb holders.

ShayneJ said:

yep busted common earth.
filament 1 earth's via filament 2 and vice versa
when both filaments are energised there is no potential difference so no
current flow and neither lights up.

but the simple answer is as always lucas!

Click to expand...

OK, Ive long forgotten my O level Physics (failed) so potential difference and filament 1 earthing via filament 2 goes straight over my head.

Busted common earth I understand.

As for Lucas being the simple answer, I don't whether that's good or bad.

Tazz070299 said:

Thanks, that will be the copper contact then. I'll have a look tomorrow and see whether there is an obvious problem, although I have tried 2 bulbs and 2 bulb holders.

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Wahay, fixed it. It was the tiny little bit of the earth copper contact which I presume is supposed to stand proud of the main contact. A judicious bit of bending fixed it. Anyway, it's now got a new MOT and I have two spare bulb holders with connectors.