Fog lights installation

[baliboy.schroeder]

Hi All,

I was given two old style fog lights to put on my van. these will be bolted to the front bumper.

I was surprised that they only had one wire coming from each unit. I was expecting two ?

If this is right...now how do I join them to one power lead and what about the grounding ?
I suppose I need a relay... one for each lamp ??  A separate switch will be located under the dash

Any advise or sketch of how to wire these lamps would be appreciated 

Regards 
Klaus

[Grantus]

Single wire (+ve), rely on the mounting to be successfully earthed to the body at the mounting point.

Good in theory, but not usually 100% effective. Best to run a second wire and ground it to a good earth connection on the body somewhere, or the battery.

Mine have two wires, to earth properly, and a relay each, to an ignition live positive switch. (Won’t come on, unless ignition is on, and will be off, if ignition is off).

Unlike driving lights, that legally should only switch on with high beam, fog lights can be wired to be switched on, with just parking lights, or headlights.

[baliboy.schroeder]

Single wire (+ve), rely on the mounting to be successfully earthed to the body at the mounting point.

Good in theory, but not usually 100% effective. Best to run a second wire and ground it to a good earth connection on the body somewhere, or the battery.

Mine have two wires, to earth properly, and a relay each, to an ignition live positive switch. (Won’t come on, unless ignition is on, and will be off, if ignition is off).

Unlike driving lights, that legally should only switch on with high beam, fog lights can be wired to be switched on, with just parking lights, or headlights.

Ok , Thanks. two wires can be arranged. does the second wire attach to inside the lamp , then to ground or is it attached where I mount the lamp to the bumper and then to a good earth connection on the body. ? And two relays.

I have a live wire under the dash that is NOT ignition activated, it is constantly live, was going to use this wire with a under dash switch to on and off.
Do you think this would be a problem ?

[Grantus]

Ok , Thanks. two wires can be arranged. does the second wire attach to inside the lamp , then to ground or is it attached where I mount the lamp to the bumper and then to a good earth connection on the body. ? And two relays.

I have a live wire under the dash that is NOT ignition activated, it is constantly live, was going to use this wire with a under dash switch to on and off.
Do you think this would be a problem ?

My negative wires are attached inside the lamp body, for weather protection.

Any live wire to the relays and switch will work, as long as you remember to always turn them off before leaving the vehicle, to avoid a flat battery. If the relay trigger wire is connected to an “ignition on” circuit, they will always be off, when the key is off. Up to you…..

[baliboy.schroeder]

My negative wires are attached inside the lamp body, for weather protection.

Any live wire to the relays and switch will work, as long as you remember to always turn them off before leaving the vehicle, to avoid a flat battery. If the relay trigger wire is connected to an “ignition on” circuit, they will always be off, when the key is off. Up to you…..

Thanks for this info. I understand what needs to be done.
Appreciate your assistance

Regards
Klaus

[KIWI]

Ok , Thanks. two wires can be arranged. does the second wire attach to inside the lamp , then to ground or is it attached where I mount the lamp to the bumper and then to a good earth connection on the body. ? And two relays.

I have a live wire under the dash that is NOT ignition activated, it is constantly live, was going to use this wire with a under dash switch to on and off.
Do you think this would be a problem ?

In the olden days, and with most current European cars FOG lamps are only on when the parking lights are on.
IMHO a much better solution.
PR

[syncro]

In the olden days, and with most current European cars FOG lamps are only on when the parking lights are on.
IMHO a much better solution.
PR

That's the way that I would do it. Just get a + from the parking light fuse.

[baliboy.schroeder]

That's the way that I would do it. Just get a + from the parking light fuse.

Thanks for that info, I shall check this out

Regards