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2rovers
11-13-2006, 10:21 AM
Can anyone give me a simple expaination of how to wire a relay switch into my headlights? I have lights in wings and rad panel and have a charging issue. Can't find any shorts, so if it is simple enough I will try relay switch.
Maybe a dumb question, do I need a relay for each of my 4 headlights?

I try to think there are no dumb questions!....

Enigma
11-13-2006, 01:25 PM
Check out this site

www.danielsternlighting.com (http://www.danielsternlighting.com)

click on tech

then click on relays

Cheers from Ontario:thumb-up:

TeriAnn
11-28-2006, 01:26 PM
Can anyone give me a simple expaination of how to wire a relay switch into my headlights? I have lights in wings and rad panel and have a charging issue. Can't find any shorts, so if it is simple enough I will try relay switch.
Maybe a dumb question, do I need a relay for each of my 4 headlights?


This is a little late but I didn't see a good answer, so here goes:

First you seem to have a couple things going on. One is that your generator does not seem to be keeping up with the load you are running. It might be time to switch to an alternator, or maybe you just need a new set of brushes.

Second you are running more power to your lights than you light switch can handle without eventually overheating the phonallic board the switch contacts sit on and burning out your barrel ignition/headlamp switch. Relays are the way to go.

Hit the local junk yard & look for a late '80's early '90s Cadallac. On the drivers side inner wing panel they have this nice sheet metal relay mount with 3 bosh relays on it. What's nice about these relays is that they are marine grade relays. The seal between the relay & socket is tripple lipped and the lead conections are potted to keep moisture off the contacts. Grab the relays & mount. Mount them on your LR's right side inner wing panel just behind the radiator. You will need two of the three relays for the headlamps.

Route a new large dia. wire from the battery (or connector with large solid brown wire), run it through a fuse to one of the power contacts of each relay.

Route a large dia blue white wire from the other power contact of one relay to all four high beam contacts on the headlamp connectors.

Route a big blue wire with red stripe from the second power contact to the low beam contact of all four headlamp connectors.

Route the ground lead form each of the four headlamp connectors to a good frame ground.

Back to the two relays:
Route a black wire from one connector of each relay's activation coil to a good ground.

Route the blue/white wire going forward from the foot dimmer switch to the second activation coil connector on the relay that has the blue/white wire going to the headlamps.

Do the same for the blue/red wire coming from the foot switch.

That's all there is to it if you are running ormal wattage lamps. If you are running haigh wattage lamps, use Ohm's law to figure out your power draw & check it against the ratings on the relay. If the high beam draw is greater than the relay is rated for you should use that third relay for half the high beams.

If you don't need the third relay for the headlamps you can run the horns off it.

2rovers
11-29-2006, 08:49 AM
Thanks for the info Terri Ann!
Once it warms up a bit here I will give your suggestions a try. Failing that I am going to try and track down a new stronger alternator.l will let you know how it goes.
Thanks
Glen

TeriAnn
11-29-2006, 09:49 AM
Thanks for the info Terri Ann!
Once it warms up a bit here I will give your suggestions a try. Failing that I am going to try and track down a new stronger alternator.l will let you know how it goes.
Thanks
Glen

Put a voltmeter between a brown wire and ground, fire up the engine, set the manual throttle to 2000 RPM or slightly higher. Turn on your headlamps (brights), heater and windscreen wipers (lift the blades off the windscreen). If your generator's output falls below 14V its time to switch over to an alternator. Either that or don't drive long distances at night in a cold storm.

But seriously if you have a LR that was positive earth from the factory the ignition/headlamp switch was not designed to carry much more current than stock configuration draws, and those extra headlamps will most likely lead to switch failure. And those are expensive puppies to replace. You need relays when running quad headlamps through the stock switch.