Help with wiring spotlights please

[deer_hunter]

Hi guys, finally got round to mounting some spotlights on the front of my truck for hunting etc. Now I just need to wire them up.

What i'm trying to achieve is to have them come on when the lights are on full beam (with a switch to stop this also), and a second hidden switch to turn them on whenever I want.

Below is what I thought might work, but im not sure about having 2 power sources coming into the one terminal. Is this possible? I guess as long as only one was turned on at a time it would be ok? but maybe too dodgy?



Any ideas and suggestions would be much appreciated. Also if more fuses are required, where would they go? and what rating? Also does anyone know what amp rating the 2 switches would need to be? I have lots of 250v 10A ones out of computers but not sure if these would be suitable.

Am also starting to think about a second battery as im already running a 250w amp, mp3 head unit, PRS radio, hard wired radar detector and occasionally a light force spotlight for night shooting.

Cheers

[kiwipete]

http://www.the12volt.com/ohm/page2.asp

Here is a great little conversion chart to use.
Simply put, watts / volts =amps
so 200 / 12 = 16.6
Therefore I would use a 20A fuse.

I would also be inclined to use 2 seperate relays for your lights, one switched by the High beam and the other by a seperate switch.
If you use as per your drawing, there is a risk of backvoltages being fed back to the high beam circuitry. while this ma cause no harm at all, I am just a little fussy now with alternate circuit feeds since I had a major meltdown of some wiring.

[Elmo]

Thw wiring of the relay is wrong for a start. The power in, needs to line up with power out on the other side.

Power in 12v - pin 30
Power out to lights - 87

Earth 86
Trigger in from high beam supply - 85

Yes, earth the neg side of lights

from pin 85 to high beam signal. Put a switch in here. This will allow you to have high beam on, but not the spots.

Also, if you want to have them on when ever you like, you need to run a second wire, from pin 85 to any 12v supply, with a switch to turn on/off.

In both of the 12v signal supply lines, I would recomend putting in say a 5 amp fuse (without working out the size) to cover any shorts/wire breakages in that wire.

Now you have a set up that 1, you can control anytime.

2, will go on and off with high beam if its turned on.

The power supply to pin 30, should be direct from battery with a 25amp fuse, and a good size wire.

[Russ]

Use two diodes - E.G. 1N4002 - about 60 cents each from Dick Smith. They will prevent anything unexpected from happening if you unintentionally leave one switch on.

[Mattman]

Unless the relay has a diode fitted you can run the relay however you want.

It does not matter what you use 85/86 and 30/87 for if there is no diode as the relay will not care.

Check the factory wiring diagram, some vehicles like Toyota's are negatively switched at the relay.

Fitting a diode to the high beam switch is a good idea as otherwise you will energise that circuit.

Matt.

[deer_hunter]

Thanks guys, that is some excellent info. Looks like ive got a job for tomorrow

[dazza85]

The only thing I would add is that you could do it with a single pole three position switch with center off. then you have only one switch and no way to back feed the headlight circuit.

Any switch can be used for this as it is only driving the relay.

[deer_hunter]

Thanks Dazza, you just answered the last 2 questions I was about to ask. Im going to go get a switch tomorrow that will do what you indicated above, which will be perfect for what I want.

Will hopefully post some pics up when its done. Cheers guys

[Clint]

Am also starting to think about a second battery as im already running a 250w amp, mp3 head unit, PRS radio, hard wired radar detector and occasionally a light force spotlight for night shooting.

Cheers

You shouldn't need a 2nd battery to just run an amp & a few spotties unless you want to run them all without the motor going. Most new vehicles have at least an 80A alternator which gives you 900W+ to play with.

Cheers
Clint

[rowinz]

I'd check with your WOF guy if a separate switch if okay. Pretty sure spots should be wired to only work when high beam is on. Thats was my experience 13 yrs ago with my Escort.

[muddyhilux]

yeh tecnically theyre not allowed to pass warent unless the do only go on while using high beam,but u can get round this by just pulling the fuses at wof time,thats what i do

[kiwipete]

yeh tecnically theyre not allowed to pass warent unless the do only go on while using high beam,but u can get round this by just pulling the fuses at wof time,thats what i do

I go to a local LTSA warrant station reguarly and failed my last warrant when my spots did not operate.
They passed them when i replaced a dodgy relay and wait for it, mine are switched independantly from the dashboard (factory switch); they can also be turned on at will regardless of the High/Low beam lights. When on they will also operate the park lights too.

[kiwipete]

Am also starting to think about a second battery as im already running a 250w amp, mp3 head unit, PRS radio, hard wired radar detector and occasionally a light force spotlight for night shooting.

Cheers

You shouldn't need a 2nd battery to just run an amp & a few spotties unless you want to run them all without the motor going. Most new vehicles have at least an 80A alternator which gives you 900W+ to play with.

Cheers
Clint

This is where one should look at a deep cycle battery as a normal lead acid battery dosent like being drained and charged repeatedly.

Im hoping to change mine over in the Terrno sometime when funds permit, as well as installing a second one for accessories, but then I have the addition of on-board PC with GPS, PRS, Stereo, Power amp etc etc.

[muddyhilux]

really kiwi pete,thats so strang,its almost like certifyers,every one has a slightly different opinion i think