Uncle Alec vs. The Prince of Darkness

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AlecGatherer
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Given Name: Alec

Uncle Alec vs. The Prince of Darkness

Post by AlecGatherer »

OK guys, you can save me a lot of hunting here.
Sorting the electrics out on my 1950 Javelin DeLuxe.
No sidelights.
No power to the front bulbholders.
I have the wiring diagram, my test light is freshly sharpened, so where do I look?
I have traced the cable bunches backwards from the front bulbholders. On the nearside I find a disparate collection of bullet connectors, one of which is a double-barrel, the others are singles with one of the bullets detached. The site is the void behind the rad directly below the n/s horn. Does this sound like the place to start?
Is there a similar collection of bullet connectors at the mirror-image location on the offside, or does it all happpen at the n/s?
There is power to head and dip beam on both sides.
Where does the junction occur between the rear part of the loom that runs from rear lights towards the switch?
Spect I have a bout of swapping old female connectors for new ones, plus some vigorous bullet cleaning.

No rear sidelights operative. The brake light switch downstream feed gives a bright n/s stop light, a bright boot-centre light, and a dim o/s stop light that seems to be earthing through the sidelight filament. Soon sort that; bad earth.
I know that I can find all this out eventually, but I am hoping that sage advice can pinpoint my field of operation and save me much squirming. My poor back!
Keith Clements
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Re: Uncle Alec vs. The Prince of Darkness

Post by Keith Clements »

A methodical and logical approach is required. First identify what does and does not work. This may give a clue to a common cause.
In your case it seems all sidelights. So look on the circuit diagram as to where that common point is. Note that the diagram may not apply to your vehicle because of modifications.
There also may be multiple issues.
I usually start at the battery. Then the fuses, before going onto check the circuit towards the faulty component. Often the fault is a bad return through the chassis to the battery so look out for low voltages, less than 12v acoss the bulb contacts, to show this.
In your case with all side and panel lights off , the fault is probably under the dash.
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Keith Clements
websitedesign
Posts: 3968
Joined: Wed Feb 08, 2006 11:22 am
Your interest in the forum: Jup NKD 258, the most widely travelled , raced and rallied Jowett.
Given Name: Keith
Contact:

Re: Uncle Alec vs. The Prince of Darkness

Post by Keith Clements »

You may find this post helps.

viewtopic.php?p=15021#p15021

It contains links to logical sequential wiring diagrams based on starting at the battery.
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AlecGatherer
Posts: 36
Joined: Fri Oct 22, 2021 6:56 pm
Your interest in the forum: Newish member with birth year Javelin de luxe.
Given Name: Alec

Re: Uncle Alec vs. The Prince of Darkness

Post by AlecGatherer »

Spot on Keith; many thanks again. That wheredoesitgoogram will save me alot of head-scratching.
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