Thread: Driving Light Relays

The relays for my driving lights are tucked in behind the left headlight. And yes, I do have an auxiliary battery and controller also mounted on that side of the vehicle under the bonnet. There's plenty of room for both.

I mounted relays and Driving Light Transformers in Bull Bar, one set each end.
Just worked out that way when fitting winch etc.
The transformer for the Fyrlyt 9000 Driving Lights that are the bulky, awkward items.

I always put the relay between batteries and lights... closer to the battery preferably..

If wired correctly, then the only long wire is from the switch on the dash which should go to earth, power from highbeam nearest the headlight or fuse box under bonnet if possible...

That way power for lights is close and a short run to lights... Anywhere under the bonnet to protect against water...

Some vehicles have space in the under bonnet fuse box, to add another relay...

Less wiring the better and the wire back to the dash being an earth is safer...

This way of doing it can make it very clean and easy to trace faults...

So thinking about this some more ....

Lights (5w LED x 32) / 12v = 13.3 Amps. Each light

I have seen them wired with one relay (30 Amp fuse) or alternatively wire the lights separately with 20 Amp fuses.

I am thinking that the best way would be a single relay, with 2x87 connections (1 to each light). Not sure if 30 Amp fuse sufficient perhaps 40. Going for relay with in-built fuse if possible.

About to look up the switch wiring again as now a bit confused about the earth and switch.

Just to be clear about what I am thinking. I have seenthis switch used in another thread
SPST Ultra Mini Rocker Switch | Jaycar Electronics


I intend to mount in next to the fog light switches and leave myself enough room for an electric brake controller switch at a later date.

Since the switch is only a SPST I thought I would wire it as shown in the diagram but taking it from the high beam wire.


My understanding from that diagram would be a wire from the high beam power at the headlight back to the switch and then another wire from the switch back to the 85 plug on the relay.

Have I got this correct?

Yes you have it correct. You don't need a relay with two 87s, just one and feed the power out of it to the two lamps, exactly as in the diagram.
Also a diode across the relay coil isn't a bad idea (1N4148 also referred to as a flyback diode).

Yes, you need to tap into the high beam circuit

Hi , I can only speak for my battery tray, but it will most likely be the same with other brands of battery tray, there is a fair bit of room under the leading edge of the battery tray for mounting relays.


You can get easy access to this area by removing your grill and the left side headlight.


This will also give you easy access to the Highbeam wire in the headlight loom.


Removing the grill and headlight is very straightforward and quick to do. These photos below will show you how.

Headlight-1.jpg

Headlight-2.jpg

Headlight-3.jpg



This is a view under the tray and that is the Headlight Connector in the bottom left side of this last photo. For the high beam trigger, just connect to the BLUE wire with the GREY TRACE.


Headlight-4.jpg

Here is a basic diagram for for driving light wiring.

DLDP.jpg