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I posted a link in the thread above your reply ... yep get a multimeter across the input voltage and check the output voltage is above 10v


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I posted a link in the thread above your reply ... yep get a multimeter across the input voltage and check the output voltage is above 10v


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Yep saw that cheers, got them ready to order if fiddling doesnt do it 🙂
 

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yeh I had a look in the PSU box. all nice and dry and I wiggled/checked all the connections and everything looked and felt fine in there. I have a multimeter somewhere so I'll have a measure and fiddle.

It's just odd that key in, one side starts up, the other side nothing but after a minute or so it will come to life not having moved and inch. just somehow comes to life and then works perfectly, and if I turn off and then on again when the lights have gone out they both come on perfectly.

I'll search through the thread and find the link. I'm sure some spares won't go amiss anyway.
What you are describing is definitely a PSU Fault. One of the capacitors or coils in the Buck/Boost controllers will be faulty and is taking ages to charge. So first key turn it has to charge before it hits the right voltage and after that, subsequent turns its already charged. If you leave it a few hours it will discharge fully and your back to square one.
 

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What you are describing is definitely a PSU Fault. One of the capacitors or coils in the Buck/Boost controllers will be faulty and is taking ages to charge. So first key turn it has to charge before it hits the right voltage and after that, subsequent turns its already charged. If you leave it a few hours it will discharge fully and your back to square one.
right so I've now made things worse, changed the faulty PSU and somewhere along way must have done something because now neither are working at all.

The LED on the PSU does not illuminate so the fault is not with the PSU now but with power supply to them. Have wiggled everything and all connections are tights.

Could this be the fuse wire has blown its fuse where I've been an idiot and buggered something?
 

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right so I've now made things worse, changed the faulty PSU and somewhere along way must have done something because now neither are working at all.

The LED on the PSU does not illuminate so the fault is not with the PSU now but with power supply to them. Have wiggled everything and all connections are tights.

Could this be the fuse wire has blown its fuse where I've been an idiot and buggered something?
get a multi meter out and trace the power back to the battery. you will find where its broken.
 

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On your set up there’s a fuse feeding the 2 PSU’s (outside the black box) and 2 individual fuses after the PSU’s so prior to the controllers (inside the big black box with the green switch on the side)

As Jay states you just need to trace it through with a multimeter. You’ll need one to trim your PSU to the correct voltage anyway.




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On your set up there’s a fuse feeding the 2 PSU’s (outside the black box) and 2 individual fuses after the PSU’s so prior to the controllers (inside the big black box with the green switch on the side)

As Jay states you just need to trace it through with a multimeter. You’ll need one to trim your PSU to the correct voltage anyway.


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I assume if the fuse after the PSU were knackered then the PSU itself would still receive power? there is no voltage across either end of the PSUs so my thinking was its before the PSUs that the fault is else they wouldn't both be without power.

Got a multimeter (turns out my OBD fault code reader thing is also a battery tester device thingy so has a multimeter function too).

The fuse outside the black box is presumably an inline fuse in that orange wire 'plugged' into the fuse box?

(You're beginning to see why I didn't take on the task from scratch, electronics are not my strong point!)
 

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Yep you’re right ... the one outside the black box supplies the 2 PSU’s,
It’s a blade fuse so you can visibly see if
It’s blown if you pull it


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Yep you’re right ... the one outside the black box supplies the 2 PSU’s,
It’s a blade fuse so you can visibly see if
It’s blown if you pull it


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So, with my poking and prodding, I have 11.5 volts coming into the PSU box (measured on the multitimer unit plugs - live on orange fuse box wire and earth/neg on the black return wire) - this is measured with engine off, just key in so should be working.

So there's power that far. But then, measuring on the connections from the multitimer unit to the PSUs (the white live wire and the black return) I get no volts....so I assume then that's a new multitimer unit thing I need?

Again, sorry for specifying exactly which bits I measured as I'm not 100% about this kind of stuff so could well be measuring the wrong thing.
 

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I’ve taken this from Jays project page (on page 1 of this thread) ... this is how the system is wired albeit with 2 individual PSU’s ... what I’m struggling with is your 11.5v with the ignition on. Why is that not above 12v? What is is when your engine is running? How old is the battery?

The orange ignition wire is the supply to switch the relay, the battery feed supplies the PSU’s once the relay is on. I don’t think you’ve got enough with 11.5 to switch the relay. Also if your incoming voltage is too low this will affect the outgoing voltage to the controllers.

If you’ve got greater than 12.5v on the relay feed when the engine is running and it isn’t switching then yes there could be a problem with the relay, or the ground connection to the relay, but I’d want that incoming voltage to be higher than it currently is.

There’s a lot of info on Jays page it helped me a lot when I put the headlights together.


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I’ve taken this from Jays project page (on page 1 of this thread) ... this is how the system is wired albeit with 2 individual PSU’s ... what I’m struggling with is your 11.5v with the ignition on. Why is that not above 12v? What is is when your engine is running? How old is the battery?

The orange ignition wire is the supply to switch the relay, the battery feed supplies the PSU’s once the relay is on. I don’t think you’ve got enough with 11.5 to switch the relay. Also if your incoming voltage is too low this will affect the outgoing voltage to the controllers.

If you’ve got greater than 12.5v on the relay feed when the engine is running and it isn’t switching then yes there could be a problem with the relay, or the ground connection to the relay, but I’d want that incoming voltage to be higher than it currently is.

There’s a lot of info on Jays page it helped me a lot when I put the headlights together.


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I see, I'll check with the engine running.

However, measured directly across the battery terminals I get 12.7 volts ish. Battery is only about a year old so shouldn't be a problem.

More digging required I think, cheers
 

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With engine running I have 13.35 volts across the orange fused supply and the black return terminals on the relay and zero volts across the PSU supply and return terminals of the relay....so I guess the relay has failed would be my assumption?

I'll get a new relay and see if that fixes it :) unless there is something I've not considered?

Cheers
 

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Yes mate that would be a fair assumption, wouldn’t explain your original fault as from memory you said that 1 headlight was sluggish, but it could’ve failed in the meantime.

You could bypass the relay to prove your theory (ignition wire straight to PSU’s) obviously you won’t get the delay.

Also bench test the relay, 12v across the coil and measure across contacts to see
If they close (measuring on ohms).

Sounds like Relay though.

Double check the green switch, can’t for the life of me if I put it before or after the PSU’s ... should be able to trace easily enough



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Yes mate that would be a fair assumption, wouldn’t explain your original fault as from memory you said that 1 headlight was sluggish, but it could’ve failed in the meantime.

You could bypass the relay to prove your theory (ignition wire straight to PSU’s) obviously you won’t get the delay.

Also bench test the relay, 12v across the coil and measure across contacts to see
If they close (measuring on ohms).

Sounds like Relay though.

Double check the green switch, can’t for the life of me if I put it before or after the PSU’s ... should be able to trace easily enough



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Yeh green switch is before the PSUs, I did think about the switch but no volts across the switch. bottleneck/problem seems to be the relay.

Yes as you say, original fault was PSU, so replaced the dodgy one and then the good one didn't work either at all so must have been really bad timing and/or luck!

ah well....if relay then easy to replace albeit the priciest part it seems!
 

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There’s a relay cheaper than the durite one ... it was about £28 I think and you could adjust the delay off time too


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There’s a relay cheaper than the durite one ... it was about £28 I think and you could adjust the delay off time too


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Right well I have sorted the problem....if you can call it that....by which I mean I still don't know exactly what the issue was, but I replaced the PSUs (went back to the original spec single PSU rather the double arrangement you had (but all original wiring still there so I can easily switch between both options if it fails as you said they did for you), also replaced all the fuses as although none looked damaged they aren't exactly expensive, and I had one of the PSU explode in my face which was another factor in reverting to a single PSU for both.

Anyhoo, long story short, the front end is looking perkier now they are back and fully functioning :)
 

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What is the last status about buying an actual set which is 'plug and play' without fiddling around baking headlight units etc? Is a complete plug and play set somewhere for sale INCLUDING headlight units?
 
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