schematic proof read

Yep - that top diagram is fine - with a fuse at the battery. The strobed brake lights get tricky because of the multiplexed module output. It's be easy if they were common GND else +12V. But using a relay or transistor to strobe them may be ok. A relay is ok if the flash rate is not too fast. Otherwise a transistor or MOSFET which is simpler if the brake lights are GND switched - the switcher (transistor, MOSFET or relay) then merely connected in parallel with the brake switch. The relay or transistor or MOSFET is energised/driven by whichever of a+ or b+ you want to use, noting a+ & b+ won't be be the same as a particular strobed LED - it might be +12V all the time or whenever a- or b- are "active". But a- or b- could also be used. But first need to know whether the brakes are +12V or GND switched, and which module output is the pulsed output - is it (a & b)+ or (a & b)-? The latter is simply tested by connecting one 12V LED from a+ (or b+) to GND, or the LED from +12V to a- or b-. That determines whether a more common NPN transistor or N-channel MOSFET is used for the input for the strobed brakes else the less common PNP tranny or P-channel MOSFET. Similarly for which type is required for the output (power) to the brakes - NPN & N-ch if ground switching, or PNP or P-ch if +12V switched. If using a relay, the polarity of the input signal (a/b+ or a/b-) is not important (merely ground else +12V connect the other end of its coil), though you must know whether the brakes are GND or +12V switched. Either way it is the same relay (ie, SPST relays are not N-type or P-type), though a transient-protection diode must be used across the relay's coil to protect the module outputs from coil-induced voltage spikes. (Hence by tradition fixing the +ve (86) and -ve (85) ends of the relay coil - the Kathode or line-end of the diode is connected to the +12V end.) Others hereon are better for opinions on relay speed switching. I do not consider them suitable for fast strobing (eg, police & emergency vehicle strobes), however after recently seeing relays used to switch lights to music, I know they can work - but I don't know how long for (still the normal ~1 million operations?)    Another consideration is incandescent versus LED brake lights. Each incandescent brake bulb is probably almost 2A (21W) compared to maybe up to 100mA (1.2W) if LEDs. That can impact relay contact life and transistor/MOSFET sizing. Furthermore, incandescents have thermal inertia and take longer to light up and extinguish than LEDs, plus the thermal fatigue from switching ages the bulbs. Hence a flashing incandescent might only last hours or days, plus they won't have the crispness of a strobed LED. And if the strobe pulse is to short, the bulbs may not light fully. Though those can be overcome (trickle-current resistors to pre-heat bulbs, and RC delays to extend on time), it'd be better to get the LED brake lights. And don't forget that if you change left-right indicators/flashers to LEDS, you probably need change your flasher can/module. (Some electronic types can be modified - just change the value of its current feedback resistor.) But don't get those expensive resistor ballasts to solve that issue - that undoes the "power saving" of the LEDs. (IE - those resistors are the equivalent of the original ~21W incandescent loads that were replaced. In fact I usually recommend using cheaper incandescents instead....)     As to a 3pst switch... WOT? And undo all that switch work? But you might be right, and they do exist. But I would still prefer your 2 switches (cool man!) and relays - hence whether you have 3A or 30A or 300A loads it doesn't matter - ie, the common 30A relay is fine for now. Increase its rating later if you have to, but you'd use the same buttons. How about a 3p4p switch to go back to a space-saving single switch? Nah - I still prefer 2 switches for earlier reasons (simpler wiring, independent) and no (off-)on-off-on of (say) the rears to get to both (off, rear, front, both). But in whatever case - relays. That means a greater selection of switches since they probably only need to be rated for 0.5A - 1A. The only mod I'd envisage over 2 buttons/switches is a 3rd if you want ONE to do both, as well as the existing 2 individuals. Does that sound appropriate to you? IE - low-power switches to control relays of (say) 30A? Normally the relays would be outside the cabin to be more inline with the light power wiring, but I presume in this case the strobe module is inside (the cabin), and the (or 2) relays are probably to be on/with the module (unless the on-off clicking noise is problem). But it should still reduce the heavy power wiring to the switches if the module is under-dash (but still suitably accessible for pattern adjustment) - not that 0.5A to 5A wires makes that much difference (I'd probably use 5A wire for both). But later if extending to 30A etc. Not that I have checked your power/current calculations... I also hope the strobe module remembers the last pattern chosen between uses...

you lost me with a LOT of that! lol the tails/brakes on the truck right now are incandescent, however they will be LED before these go on, i had led's on them, and they got smashed, meeting up with the guy who hit them to get money for them today, ordering off ebay probably in the next 2-3 days, when i figure out exactly what i'm doing... the strobe speed will be quite fast, they are an emergency light i'm putting on the truck, and i'm 99.9% sure that it's a switched +12v for the brake lights, not switched ground, which i would think makes it slightly easier... as for the module, i'm planning on putting the module above my rear view mirror, and below the head liner of the truck, it's very small, and i THINK it remembers the last pattern chosen, or i will have to wire it slightly different, maybe hardwire the unit into the battery, then just switch the outputs... depends on where the power switch the module comes with is... i don't remember there being one on the module it's self... but i could be wrong i was thinking a transistor, because it works similar to a relay, but with no working parts, right? as for the flasher module (for turn signals) they are already taken care of, i've got an LED replacement in, last week (before i removed the broken LED tails) the only lights on the outside of the truck that were not LED, was my highmount stop light, headlights, fog lights and driving lights (head, fog and driving lights can't be LED, they don't make LED replacement bulbs for them) and the high mount i haven't had a chance to get a new one yet... what i'm doing: headlight strobes (1 each side) bar lights in grill (one each side) bar lights in rear door(side) window (1 each side) bar lights in rear window (1 each side) both brake lights (1 each side) and 2 tail light strobes (1 each side) the grill and side bar lights are 4 watts a piece, the headlight (and tail light) led strobes are 4 w a piece, the rear window bar lights are probably around 2w a piece, and i'm not sure about the tails, can't find any technical specs on them... though, now that i think about it, there is a load equalizer that comes out the rear of the light, with a plug, if i were to just plug the power and ground wires into the load equalizer plug, would that work? i don't need the load eq, because i've got the LED flasher, and in fact it undoes all of the electronic benefit to having low current LED's in the first place... so i would need to put a diode in so the positive input from the strobes, doesn't feed back into the other brake light, and that the ground from the light doesn't give a positive ground for the strobes... does this make sense? let me draw a pic, and i'll post it...no signature needed

yeah, the more i draw, the less it makes sense... it worked in my head, but the switched ground wouldn't exist for the strobes, as it would take the solid ground of the normal circuit... if they were both switched ground, i would be golden, or if they are both switched positive i would be golden... going to be a matter of waiting to see when they show up... for all i know, this kit MIGHT be a switched positive..., in the grand scheme of things, it makes no real difference in the module... it's just where they want to put the switching circuit... these are the tail lights they are connecting to, btw http://www.ebay.ca/itm/130574652331?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649 no signature needed

Ah - they call it a "load equalizer". What a clever marketing term for a load that uses and wastes as much power as the original bulbs being replaced. LOL! It's the way they scam extra money out of those that use LEDs for environmental or power reasons. Fit LEDs, Flashers don't work. Buy & fit this. That worked, but now I found out I'm using the same "old" power. Ah - the fit this new flasher module and dump the "load equalizer" we sold you.    And btw, I've been thinking of your truck as an articulated vehicle (heaps of lights down the side). Except for that 4 year old that commented on my "dirty yellow truck", we tend to use trucks as being articulated and not 4WDs nor Hummers etc. [ May that kid see his 5th birthday (sorry, a bad taste thoughtjoke). Damned youngies just haven't learnt NOT to be truthful & forthright! And just because he was 100% correct and I agreed with him is no excuse! ] Being all LEDs makes it easier. The simplest would be to DPDT switch them in to the module, else use a transistor or FET. But I'll re-read and think about it. And determine if braking is to override the strobed brake lights. (Maybe you stated that above; otherwise yes, no, don't care, or only if driving? (Though the latter should be an alarm that you are driving with strobing lights - assuming that is illegal).)    Thanks for fitting all LEDs up front! Till later...

man, you are good at confusing me... don't need a buzzer at all, it will be obvious enough they are all on when they are on, there are laws to me driving with them on, i know them, i'll follow them... i'm also going to have lights inside the truck to indicate the lights are on (wired into the switches) and i don't want it so that the brake lights DON'T work, when the strobes are on... i hear what you're saying about the DPDT relay, which would work... except that would cause the directly above situation...no signature needed

i think i'm just going to not worry about that at this point, and hope they come in with a switched positive! lolno signature needed

The brake override is easier. Then it is just diode-ORing the 2 sources - ie, from module +ve output (via switch) via diode, and brake switch +ve output via diode - to the +12V of the brake LEDs.

oldspark wrote: The brake override is easier. Then it is just diode-ORing the 2 sources - ie, from module +ve output (via switch) via diode, and brake switch +ve output via diode - to the +12V of the brake LEDs.

hey, sorry i've disappeared for a while, been busy with old jobs and new jobs and trying to keep busy, and moving to a new place and all that jazz! you lost me here... this changes it from a switched positive to a switched ground right? i hate to be a pain, but can you draw that out for me? it makes more sense when it's in schematic form for me i still haven't gotten any closer to actually buying or installing all of this, other than the switch mounting thing is all done and sitting in my garage, ready to go in, for when ever i have this all wired up and such... but i've got a few things ahead of it... HAM radio first, which is what is going to get me a viable excuse for putting the lights in, not that i don't already have one...no signature needed

It's like the following.... Where the lower "positive triggers" are the input +12V from your flasher or switches etc, and the "to alarm..." is the output to the +12V end of the LEDs. Hence the LEDs are on if one OR the other input is +12V.    The other way that can be done WITHOUT diodes is if the inputs are GND switching - then join the inputs and connect between LED- and GND with LED+ to +12V.

that way is both brake on truck is switched positive (which i am about 99.9% sure it is) and the flasher is also switched positive right? in which case, that schematic, the brown would be where the actual light goes, and the green would be the flasher, and the blue would be the brake wire it's the other way, where the truck is switched positive and the flasher is switched ground that has me confused...no signature needed