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#640278 25/05/20 07:34 PM
Joined: Jul 2016
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T
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Evening Folks
Have been out for a drive this evening only to notice that when I brake the rear light and brake light on one side goes off, but with foot off the brake the rear light is on.
Any ideas why this would be and what I need to do to rectify this.
thanks
Trev

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Salty Sea Dog
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You have a defective earth somewhere - probably in the earth leads / connections to those lights.


Graham (G4FUJ)

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First step is I'd check the bulb, to make sure it is seated properly in the holder, and then check the earth,


"Y mae dafad ddu ym mhob praidd"
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Like Graham, if your lights do bizarre and unfathomable things then it's usually the earth somewhere

K

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The earth to the chassis at the rear is in the far corner under the back valance. Remove the rear wheel and look inside to the right & rear wards. It is on the chassis.


JohnV6
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Hi Trev,

Whilst upgrading my 1997 +4 amber indicators to clear lens DRL/ indicator lights, it was necessary to swap light fittings and run extra cables some of which needed to pick up an earth.

I swapped the single bullet connectors for doubles as this was the easier way without the need to cut the existing wires.

My point is, that it was amazing how many of the existing earth connectors were only just holding into the connector and it was a wonder that I didn't have an earthing problem a long time ago.
So I would take the above mentioned path of checking the earths as a first point of attack. The earth connectors for the rear lights are easy to access if you look under the bumper and up towards the rear light cluster. I fount that removing the spare wheel helped with certain points of access.


Hope this helps..


Rob.

Last edited by BLUE+4; 26/05/20 02:23 PM. Reason: typo

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Rob B.
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Had a look today appears to have been the earth in the rear valance, all working okay now.

Thanks for the advise.

Trev

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Trev,
I suggest then having solved that that you look at all the other earths. You really need to take them apart as the corrosion is not always visible.
Here is the Roadster set up.
https://www.gomog.com/allmorgan/Roadster_earth_grounds.html
John


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will do thanks

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Check inside your winking light for the earth.
I had similar on my 4/4. I did the “wiggle test” by wiggling the wires under the wing. It recreated the effect.
Took the lens cover off and saw the earth (black) wire was a bit loose. It was pop riveted to the light body and not a tight connection.
Drilled it out, cleaned everything, bolted it back with a stainless bolt. Worked well after that.


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