Boomslang Harness Headlight Fail

Fitted a boomslang harness a year or so ago. Last night the Mrs came home from work to report she could get side lights and main beam only. There's a couple of relays in the harness, is one for headlights and one for main beam? If so I'm presuming the headlight one has failed, but that's just me guessing!
The only thing throwing me is that the Mrs said when she first noticed the headlights weren't on she waggled the main beam lever back and forth and they came on for a while before they went off again.
Sorry, but forum search not working and I've Googled it but nothing coming up for this specific problem.

Possibly the switch then if a bit of wiggling temporarily fixes the issue?

bluedog333 said:

Possibly the switch then if a bit of wiggling temporarily fixes the issue?

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I know, but it was the main beam switch wiggling that made the headlights come back on! The switches trigger relays now, you'd think the main beam switch would only affect the main beam relay? I need to find the instructions for fitting the harness

Main beam switch also operates dipped beam.

Two people one wiggling switch other with their hand on the two relays, always worth swapping the relays over or fitting new ones.
But does sound to me like the switch is knackered, they are crap even when new, mine has been playing about for the best part of ten years!

Just power up the relays on the switch side to prove relays are fine.
+1 on faulty switch.
I have now wired in a rocker switch in case of emergencies.

Had the same problem on a standard lighting harness. Turned out to be loose connection in the switch (Britpart).

You do know that those switches can be dismantled, cleaned , adjusted and reassembled? Thats why they are made like that.

Excellent suggestions. Doing all of the above checks and possibly dismantling the switch is going to be my saturday afternoon. Thanks gents.

corroded relay terminal
Cleaned it up and it's working again

Al2O3 said:

View attachment 198400 corroded relay terminal
Cleaned it up and it's working again

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Always worth puting some grease on any electrical contacts that the weather can get to

lynall said:

Always worth puting some grease on any electrical contacts that the weather can get to

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Done that and tied a small sandwich bag over it

Al2O3 said:

Done that and tied a small sandwich bag over it

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Ah see the bag may be a bad idea, any damp WILL get in and then sweat like a greenhouse.

lynall said:

Ah see the bag may be a bad idea, any damp WILL get in and then sweat like a greenhouse.

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I know, I'm going to keep an eye on it. See which is the worst evil

Al2O3 said:

I know, I'm going to keep an eye on it. See which is the worst evil

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See it all the time at work, rotten and corroded electrics due to the installer or repairer thinking they are doing a good job.
Example using heat shrink crimp connectors which are brilliant, then wrapping said connector in black tape which ensures any moisture that gets in stays in and eventually works its way into the connector/loom wrecking it again.
Wurth 2000 spray is quite good as in the Wynns stuff.

lynall said:

See it all the time at work, rotten and corroded electrics due to the installer or repairer thinking they are doing a good job.
Example using heat shrink crimp connectors which are brilliant, then wrapping said connector in black tape which ensures any moisture that gets in stays in and eventually works its way into the connector/loom wrecking it again.
Wurth 2000 spray is quite good as in the Wynns stuff.

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I'm convinced, I'll take it off

Al2O3 said:

I'm convinced, I'll take it off

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Wynns Viscotene is the stuff I was trying to think of, used this stuff as the hgv wrecker peope in Norfolk (Boniface?) used it on their new builds.

Thats got very hot due to high resistance, I would check over the whole circuit paying attention to earths as well as lives, also I would put an appropriate fuse on that, a fuse is there to prevent damage to wiring.

Also, are your relays under the bonnet? Unprotected? at least get a weather proof relay box for them!

nobber said:

Thats got very hot due to high resistance, I would check over the whole circuit paying attention to earths as well as lives, also I would put an appropriate fuse on that, a fuse is there to prevent damage to wiring.

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Hadn't noticed that. It's easier to see on the picture, but I haven't really looked at the picture much. Just directly at the relay socket and it's not so obvious like that.
Presumably that's due to the poor connection due to the rust.

nobber said:

Also, are your relays under the bonnet? Unprotected? at least get a weather proof relay box for them!

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Aye, been meaning to put them in something
To busy focussing on the turbo issue I suppose.