Another aux. light wiring question (I've searched already)

[96discoXD]

I'm installing four Hella 500 lights on the front of my rack on the topper, and two work/flood lights on the back of the topper. The Hella 500 lamps have stock 55w bulbs, I believe the rear flood lights are also 55 watt bulbs.

I am running seperate relays, switches, and wiring for each pair of lights mostly as a reduncancy so I don't lose any substantial amount of wiring should one system fail.

I've sorted out all but two items that I'm still trying to decide on.

First, in order to mount the relays where I want them (forward portion of the LH inner fender panel) I am going to install a junction block, which will have the added benefit of only having to install one terminal on the battery, thus keeping the wiring a bit cleaner. Since I'm an electrical newb, I'm not sure what size wire I need to run to supply power to all six of the 55w lights I'm installing. The inline fuses will be in the individual wires from the junction block to the relays. Will 8ga. wire be sufficient from the battery to the junction block?

Secondly, rather than attaching to the existing high beam wiring as suggested in the Hella wiring diagrams, I want to attach to a different fused power source that will allow me to run the lights off road without the high beams engaged. The two options I am considering are as follows:
* Run an additional power source from the battery or junction box, install inline fuses prior to the switches.
* Locate an alternate fused circuit (I'm open to suggestions here) and utilize that for the Hella lights

The rear lights will be powered (to the switch at least) via a non-switched always hot 12v source so that the rear fogs can be turned on if desired while camp is set up. Obviously they will be used sparingly to prevent draining the battery.

Any input from some more electrically inclined experts here would be very much appreciated. I am going to begin fabricating the wiring harness for the rear lights tonight and hope to install all of the wiring for the lights this weekend.:coffeedrink:

 

[sargeek]

For the forward facing lights, I would install a ON/OFF/ON switch. In the first position, the off road lights will come on with the brights, in the other on position manually turns the lights.

The advantage of the interconnect with the brights, allows you to dim all your lights with one switch. Helpful when meeting oncoming traffic on the trail. It takes too much time to fumble with many switches on a trail.

You can also do the same with the rear lights. In the first ON position, the rear light come on with the reverse lights, and in the other ON position manually turns the lights on for in camp use.

 

[96discoXD]

Those are probably good ideas, but I don't want to bother with the complexity right now and I already have a set of good switches that I don't want to replace, so I'm looking at one or the other.

I may just wire the forward lights into the hi-beam circuit for now since I can use the hi-beams in any circumstances where I would be using the off road lights anyway. Would using the high-beam wiring to draw the 12v power for both pairs of front lights be too much? I suppose otherwise I could run the center forward lights from the high beam and the outers which are going to be run angled out slightly from the low beams so I have the option.

For the rear lights I'm not concerned about them coming on while backing up so I will probably wire them directly to the battery with an inline fuse instead for the 12v power source.

 

[angusdevil]

Those are probably good ideas, but I don't want to bother with the complexity right now and I already have a set of good switches that I don't want to replace, so I'm looking at one or the other.

I may just wire the forward lights into the hi-beam circuit for now since I can use the hi-beams in any circumstances where I would be using the off road lights anyway. Would using the high-beam wiring to draw the 12v power for both pairs of front lights be too much? I suppose otherwise I could run the center forward lights from the high beam and the outers which are going to be run angled out slightly from the low beams so I have the option.

For the rear lights I'm not concerned about them coming on while backing up so I will probably wire them directly to the battery with an inline fuse instead for the 12v power source.

The power coming from the highbeams won't be powering the lights, it will only be turning on the relay which will get its power directly from the battery. There only needs to be a small amount of 12v to activate the relays.

 

[96discoXD]

The power coming from the highbeams won't be powering the lights, it will only be turning on the relay which will get its power directly from the battery. There only needs to be a small amount of 12v to activate the relays.

Thanks. I thought that would be the case, but like I said I'm no electrical wizard, I wanted to be sure before I went splicing into any of the wiring harness on this truck. It's 20+ years old and everything but the AC works, so I don't want to screw it up.

 

[angusdevil]

Thanks. I thought that would be the case, but like I said I'm no electrical wizard, I wanted to be sure before I went splicing into any of the wiring harness on this truck. It's 20+ years old and everything but the AC works, so I don't want to screw it up.

If you don't want to screw anything up for sure then, just keep it all isoloated from the headlamps. Put a 3 way switch on there where its UP for front and back and DOWN for just the fronts. K.I.S.S. works well with electrical.

 

[87FoRunner]

This is how I am wiring my roof rack. May be of some help to you.

 

[96discoXD]

Thanks for the diagram, the master relay and switch idea is interesting, I wouldn't have thought of that. Not a bad idea to be able to turn all of them on or off with one switch. I may have to consider that at some point.

I started doing the wiring last night, I hate doing that kind of work, it's so tedious fishing wires and making them all look good, or rather, not be a mess of spaghetti that looks terrible. I'm taking the time to run all of my wiring in a loom and secure it as needed to protect it from abrasion. It's probably overkill, but I hate seeing messy wiring.

I found a couple wires under my dash that looked like they had a wire nut on them, but it wasn't there so there was a bare wire connection. That's going to get rectified tonight with a proper connector and some heat shrink tubing.
I have to trace the wire to see what it belongs to.

 

[87FoRunner]

Not only can you turn them off and on at once (with either high beam circuit or master switch) you only turn on the lights you have selected with the (rocker) switches.

Examples:

Scenario: Backing out of dark driveway. :088:
Flip Reverse light rocker switch
Hit master switch

Scenario: Backroads driving :smiley_drive:
Flip Rocker switches for (outer and inner is how mine will be wired) Front Lights
Hit high beams on truck
(oncoming car)
Hit high beams off (all lights go off)

Scenario: Mall Cruising :bike_rider:
Flip all the rockers on (all 6 lights)
Flip master switch
Bling Bling.

 

[barlowrs]

What relay do you use for the master? It would have to be considerably larger correct? As there is current for ALL your lights flowing through that one relay or am I thinking of it wrong (I am not very electrical)

 

[87FoRunner]

An 80 amp from a Volvo. Made by Hella. Uses 1/2" terminals as opposed to regular 1/4" terminals. From the specs I found it is for a big 12v air compressor for rear air suspension or something.

I am running two 100w KCs as outer (spot) lights. Two 55w HID ******** Cepek lights as inners (driving on steroids beam). Reverse are two 55w Hella Micro Fogs.

I have also considered running a 12v Stud (like this ) and ground in case I ever need to run some temporary aux. lights or maybe a small inverter. (run a switch up there so it is not constantly "hot," for say like a handheld light or something small, under 20 amps)

 

[evldave]

An 80 amp from a Volvo. Made by Hella. Uses 1/2" terminals as opposed to regular 1/4" terminals. From the specs I found it is for a big 12v air compressor for rear air suspension or something.

I am running two 100w KCs as outer (spot) lights. Two 55w HID ******** Cepek lights as inners (driving on steroids beam). Reverse are two 55w Hella Micro Fogs.

I have also considered running a 12v Stud (like this ) and ground in case I ever need to run some temporary aux. lights or maybe a small inverter. (run a switch up there so it is not constantly "hot," for say like a handheld light or something small, under 20 amps)

An alternative would be for your high-beams to power the switch circuit in the cab - this would eliminate one relay (the big one). Just tap in the high-beam power after the main switch and it will power your switches (which will then power your relays and lights).

This has a couple advantages:

One less relay, one less thing to break.
One less 'specialized' relay - if your high-power relay breaks down, and it's a specialized part, can you easily find a replacement?
Less connections on your main power line - less voltage drop, so more power to your lights.

And some general comments (sorry if you already know these, just putting them out there):

Ground wires should be comparable to power wires in size. It's a full circuit so you can 'choke' your power via the ground wire too.
Fuse all separate circuits. On my light setup, I fused the main line, plus each separate light circuit (before the relays). I fused the switch line coming from the main, but not at each switch.
Use bigger wire if you can fit it in/afford it.
Make sure your grounds are good (see a trend, this is where a lot of accessory hookups come up short, grounding is key to bright lights)

Not to nitpick 87FoRunner's diagram, but I put my 'master switch' before each individual light switch, so it shut down the whole switch panel. I ran them all w/a single circuit (no fuse box) since they are low current draw, and ran the relays off a fuse box on my roof rack. This solves the fusing problem, and allows 2 wires run up top for lights (one main power + 5-conductor control circuit).

Everyone has different preferences on how to wire everything up, search around here you'll see lots of threads on how this stuff goes together - there are lots of ways to do it right and have it work and be safe - except for people who buy full kits, I doubt any two setups are the same

 

[96discoXD]

I just ended up pulling power for the relays and the lights from a direct 12v source (battery) I ran a 4ga. lead from the positive battery terminal to a junction block, where the power is distributed to the relays via independant switches for each bank of lights, and also to the lights via the relays when activated. I don't forsee using the lights much if at all on the street and most the switches are in easy enough reach that I won't have a problem turning them off if I encounter a vehicle traveling in the opposite direction.

I do still like the idea of a master switch though so I may re-wire the 4ga. lead with a relay and switch later on to incorporate that into my design.

I have to button a couple of things up and then I should be able to test them to see how they look. I did end up modifying the wiring harnesses that came with the Hella 500 lights and only used the stock 18ga. wiring for the front ligths out of ease, although I will probably redo that later. Everything else is wired with 12 ga. and I've been particular about making sure I have good chassis grounds too.

 

[87FoRunner]

I understand where Dave is going and it is cool. I understand is theory and opinion. For reference, I am using the Volvo big ol' relay right now since I currently have 3 of them and they are of high quality. If the master were to fail, I could simply bypass it and have the rack lights turn off and on by the regular switches.

My main thing with a "Master Relay" was to be able turn the lights on independent of everything, or have them on at a selected time. (High Beams) This also allowed me to turn on (and off) all the lights at once with the flip of a single switch.

No fuses (other than the distribution block) were illustrated in the diagram to reduce clutter on my pretty pictures. But of course always use proper fusing, grounds, and grounding points. I am running a ground stud on the rack to an 8 ga. wire going to the frame of the truck. This was to prevent a "ground loop." The distribution mini fuse block has 6 outlets, 4 of which I will be using for switches, one for CB radio power, and another for the Bluetooth box from my Pioneer radio. I can always go to a bigger distro block if needed down the road for say, Ham Radio, permanent GPS charger, etc.


I also thought about tying the master relay to an aftermarket alarm circuit. This way, whenever the alarm goes off, you get a light show, drawing more attention to the thief. :wavey:

 

[evldave]

I also thought about tying the master relay to an aftermarket alarm circuit. This way, whenever the alarm goes off, you get a light show, drawing more attention to the thief. :wavey:

That is a fantastic idea! Gotta think about how to make that work w/my factory alarm (that flashes the lights when in alarm mode)...hmmm, gonna have to dig out the FSM now and see what I can screw up

I was figuring you were wiring more stuff into the switch circuit, that's the problem w/drawings...put everything in there and it gets cluttered, only put some in there and some internot dork's gonna point out all the missing stuff :sombrero: