Wiring led trailer lights

[Northeastfarmer]

I’m fitting some new led trailer lights to the grain trailer

Four colours on the led lights
Blue
Red
Black
Yellow

Four wires coming from trailer junction box
White
Red
Brown
Green

I’ve wired
red to red
Yellow to green
Brown to black

Indicators working fine, brakes working fine but can’t get lights on
Help please

 

[roscoe erf]

I’m fitting some new led trailer lights to the grain trailer

Four colours on the led lights
Blue
Red
Black
Yellow

Four wires coming from trailer junction box
White
Red
Brown
Green

I’ve wired
red to red
Yellow to green
Brown to black

Indicators working fine, brakes working fine but can’t get lights on
Help please

is the black not an earth never seen those colours on a led light did it not come with instructions blue is normally fog light

 

[Northeastfarmer]

is the black not an earth never seen those colours on a led light did it not come with instructions

No bloody instructions! I’ve tried looking on the net but drawn a blank

 

[roscoe erf]

No bloody instructions! I’ve tried looking on the net but drawn a blank

trail and error then blue is usually a fog light so im gussying Chinese made

red brake lights black or brown side lights green/yellow indicators white earth

but I have seen black on led lights as an earth

 

[Northeastfarmer]

trail and error then blue is usually a fog light so im gussying Chinese made

red brake lights black or brown side lights green/yellow indicators white earth

I got them off amazon but aye probably Chinese! I’ve been doing trail and error but nothing lights them up...I’ve soldered them now so don’t really want to part them unless I have to

 

[yellowbelly]

No bloody instructions!

I got them off amazon but aye probably Chinese!

Here you go....

...hope that helps

You've got 4 wires for 4 jobs (LH ind/RH ind/stop lights/tail lights) so, probably your earth wire from the junction box is connected to your tail lights. Maybe the new lights should be earthed to the chassis (and your earth from the junction box too) IYSWIM.

Looks like you need to get your multimeter out. Good luck.

 

[Chuckie]

I'd guess

white to black
red to red
green to yellow
brown to blue

but it would be a stab in the dark and might blow all your fuses

 

[Robt]

buy yourself a power probe from snap on, £65 . You attach it to your battery and it will tell you a true earth, give 12v at push of button................. If you insist on buying cheap rubbish off amazone, it will save you frying something

 

[Northeastfarmer]

buy yourself a power probe from snap on, £65 . You attach it to your battery and it will tell you a true earth, give 12v at push of button................. If you insist on buying cheap rubbish off amazone, it will save you frying something

I’ve bought plenty of lights off amazon and they’ve been very good quality...there’s nothing wrong with the lights I obviously haven’t got them wired correctly

 

[Blue.]

I’ve bought plenty of lights off amazon and they’ve been very good quality...there’s nothing wrong with the lights I obviously haven’t got them wired correctly

I usually test them on a battery charger to decide what’s what.

 

[agrimax]

You got there before 4 years ago.....but some of the wires were a different colour......https://thefarmingforum.co.uk/index.php?threads/led-trailer-lights.76796/..

 

[Simmy]

Blue is the side lights

 

[Mur Huwcun]

The white on the trailer is the earth cable therefore the way they are now they’re not earthed properly but earthing back through the ither light circuit.

Whip a lamp off and try blue or black as earth on a battery and work out what the others do

 

[Northeastfarmer]

The white on the trailer is the earth cable therefore the way they are now they’re not earthed properly but earthing back through the ither light circuit.

Whip a lamp off and try blue or black as earth on a battery and work out what the others do

So I need to earth the white cable coming from the junction box?

 

[Mur Huwcun]

So I need to earth the white cable coming from the junction box?

No, the white coming from junction box is the earth wire from the 7 pin plug

 

[Northeastfarmer]

No, the white coming from junction box is the earth wire from the 7 pin plug

Ok you’ll have to excuse my ignorance as electrics aren’t my strongest subject...what do I need to do with the wires?

 

[v8willy]

Ones I got lately were
Blue = Tail light
Yellow = indicator
Black = Earth
Brown = Stop

Get 2 wires running off an old battery or use the battery charger, play about with the wires till something lights up, then you know which is the earth & it's easy from there.

Trailer (should be)
White = Earth
Red = Stop
Brown = Tail lights
Green = Right indicator

If that doesn't work then it's back to the plug & go from there just using the numbers

1 = Yellow / Left indicator
2 = Blue / fog
3= White / Earth
4 = Green / Right indicator
5 = Brown / Left tail
6 = Red / Stop lights
7 = Black / Right tail

 

[Northeastfarmer]

Ones I got lately were
Blue = Tail light
Yellow = indicator
Black = Earth
Brown = Stop

Get 2 wires running off an old battery or use the battery charger, play about with the wires till something lights up, then you know which is the earth & it's easy from there.

Trailer (should be)
White = Earth
Red = Stop
Brown = Tail lights
Green = Right indicator

If that doesn't work then it's back to the plug & go from there just using the numbers

1 = Yellow / Left indicator
2 = Blue / fog
3= White / Earth
4 = Green / Right indicator
5 = Brown / Left tail
6 = Red / Stop lights
7 = Black / Right tail

Thanks

 

[Mur Huwcun]

Ok you’ll have to excuse my ignorance as electrics aren’t my strongest subject...what do I need to do with the wires?

As mentioned, hold the black lamp wire on battery negative and touch the other three in turn on the positive to see which one does each function. If they make no sense try the blue as earth but black should be ground/earth on lamps. It’s confusing as black is one of the side lights in the 7 core cable colour scheme!!

 

[jd6820]

Silly question, but have you looked on the back of the light units themselves and see if the colour code for the wires is cast into the plastic? Reason I ask is the last set I had to work with didn't have instructions but I did spot the colours mapped onto the back of the light...