Wiring spot lights up - Not done this before?!!

I ran the cable though the box section of my roof bar and straight through the roof, plenty of sealant under the fixing plate. Cable the runs though the internal double door sking were the seatbelt is and out the bottom along the floor under the carpet. I'll get some pics assuming she makes it through today's MOT

Right...

You will need relays... one for a pair

Best practice is to return the earth to the battery with the same size cable you used for the live which needs to be able to carry the current draw

For my roof lights (which are 100w each for 400w) i used two lengths of flexi cable the same stuff your hover etc is wired to the plug with

it can take 16 amps @ 240V so i used the two core (both browns) for the two outside lights and another two cores (the two blues) for the inside ones...

The earths where then taken to the battery by the remaining cores (the two yellow and green)

I ran the two big cables down the windscreen piller and into the bonnet through a gap in the plactic panel underneath the wipers

They go to the two relays that are under the bonnet well out the way of water

Now this is where is gets complicated... You carnt wire up the relays the normal way as the headlamps are constantly live and the earths are switched

you will need to follow the wiring diagram below for them to come on with the high beam



Hope this helps

JerseyJimny,
Thanks that does help a lot. Now comes the part that shows how poor I am with electrics> :whistle:

Am I correct in thinking:

Relay
3x spots = 2 x relay

Wire gauge
Operating Voltage: DC 10V - 30V per spot = Max 90V
6 LED giving 18W per spot = 54W total

Haven't got a clue how to work out the Amps for the wire gauge I need

Switch
With my wish to have the spots work with the following options:
a) main beam ON / spots ON
b) main beam OFF / spots ON
c) main beam OFF / spots OFF

Would I need a switch that had>

>12V+ feed for relay from switch
>High beam trigger - (the 2 mm purple one in the diagram)
>Spots only (Spots ON and main beam OFF)
>Spots OFF (unless HB trigger active)
>12v-


And now I am lost again for what I need ....


When I mention circuit diagrams in crayon in my previous post that was so *I* could understand it ..

Boomer wrote: Haven't got a clue how to work out the Amps for the wire gauge I need

IIRC places like Halfords label their wire up with the task's it's designed for. I think you'll be needing the thicker gauge for driving lights.

The fitting kit they sell says the following: 17 amp cable for 2 x 55w bulbs; 27 amp cable for 2 x 100w bulbs

Jimnyash wrote:
17 amp cable for 2 x 55w bulbs; 27 amp cable for 2 x 100w bulbs

So as all three only add up to 54W I could run a single strand of this for 12V + for all three spots?

Is the need for two relays now defunct due to the low W power. Could I get away running all three from a single relay?

The gauge and number of the cables I need to run decides how I will have to route it, so the thinner I can get the better. Best case would be a two core 17 Amp if my brain has worked (one power feed and one earth feed), feel free to correct me

I use a two core 17amp cable for my rear work light which is 55W

That is ran off one relay

As for switching...

A) Take a feed from your headlight to your switch and then take that feed from your switch to your relay

B.1) Take a feed from your battery (if you want to be able to switch them on without the ignition on) to the switch and then from the switch to the relay

B.2) If you want them to come on only when the ignition is on then find a 12v source which is switched on with the ignition... easiest feed to find is the 12v cigaret lighter socket... tap a feed from that to your switch and then to your relay

C) your switch should have a OFF position that will take care of that