Thread: Defender Headlight Switch

and somethings on a Defender never changes.....

Fitting a rely for the head light switch is something Ive been doing for 20 odd years and doesnt require anything clever to be purchased.

The first time I did this mod was on a 1978 Series 3 and have done it since.
As already mentioned mostly when upgraded globes are fitted is what causes the issue (apart from the fact no relay is a stupid idea).

Regards
Daz

P.S oh I still like that nice modern look switch the OP did, and rather than shoot someones idea down in flames, add to the positive idea they have.... "great switch, but you should add a relay to it"

I bought a headlight relay kit a long time ago. Before I got around to installing it (and still haven't - just raided kit for bits) switch burnt out - as they all seem to. Quick fix that I find satisfactory was to install a heavy two way toggle switch on right side of steering column. Easy fit as plastic covers have been left off. Original headlight switch still works parkers and instrument lights as normal. Substitute one just switches headlights on low or high beam independent of original switch. Also bypassed the standard dipswitch and the relay down by the fuse panel which the headlight switch current goes through. Idea of this obviously to prevent accidental fast flattening of battery by forgetting to turn off headlights when stopping motor. Despite having been caught out doing this, I prefer being able to have headlights on without taillights and /or without motor running. Especially for stationary lighting eg in a paddock.


One apparent advantage of these simple modifications is having slightly brighter headlights with standard globes due to less voltage drop. The headlight current only goes through one switch. With the standard setup, it goes through three switches, which would each cause small voltage drop. ie The headlight switch, the dipswitch and the relay controlled by the ignition switch. Also bypassing maybe three feet of extra wire down to and back from this relay would if anything further help reduce voltage drop. However, note that the standard wiring system should not have many problems with a relay kit installed as only the small current necessary to actuate the relays then goes through it. The only "switch" the main current goes through is the relay and then through a shorter distance of heavier wires than the standard ones.

As said the switch may help, but you are more just treating the symptoms and not finding a cure. The most important thing to do is add a relay as they dont have them standard. They will melt with normal globes and by just changing the switch it will just move to the next weak point. I replaced mine with a Traxide kit some 10 years ago and have not had any dramas since. It is also cheaper to buy the RRC switch and just cut and replace the connectors.

Originally Posted by CraigE

As said the switch may help, but you are more just treating the symptoms and not finding a cure. The most important thing to do is add a relay as they dont have them standard. They will melt with normal globes and by just changing the switch it will just move to the next weak point. I replaced mine with a Traxide kit some 10 years ago and have not had any dramas since. It is also cheaper to buy the RRC switch and just cut and replace the connectors.

And if you fit relays close to the headlights, you cut out a couple of metres of wire which will give a bigger voltage drop than the headlight switch contacts. And even better if you source the power for the relay from the alternator, where the voltage will always be slightly higher than at the battery when the engine is running.

John

Originally Posted by BadCo.

Did you read everything?

Yes

Digressing slightly from the original post but does the lower current draw from fitting led globes or full led headlights negate the need for a relay setup?

Paul.