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relays, lights, fuses and wiring


Tulsa, Ok
okay so i got my headache rack mounted up and i found the lights i want.

ive got 4 dick cepek baja 100w lights on order.

So with that said. Ill be adding two more later on to mount in reverse so ill wire those up seperatly with that time comes

So what relay should i use.

i figure ground the lights right at the headache rack. and tie the 4 lights in on a single power wire. to a relay, in cab toggle and to the battery.

But if any body has a diagram on how to wire a relay (I hate wiring) and what amp i should us (some calculators possibly?) and wiring guage i should use.

gonna shoot for having these on this weekend possibly


Tulsa, Ok
works for me.

as for the vodka :puke: :puke:
If it was me I would have the relay as close to the lights as possible.

Since you are wiring them in parallel I suspect (so they all are controlled by one switch) the feed wire from the battery to the relay would be the largest gauge (I suggest 8 g)
The wires going to each light would be 12 g.

Buy a BOSCH relay or 2.

You can wire them up like the headlight circuit upgrade.


The Token Canadian
Staff member
A 100 watt lamp is gonna draw 8.3 amps at a nominal 12V...with your engine running and alternator producing roughly 14V that amount will be reduced to roughly 7.2 amps. Lets just use the 8.3 draw for safety.
4 lamps are going to draw 8.3 x 4 which will be 33.2 amps.
You are going to have to use either a 40A relay or 2 20 or 30's if you can't locate a 40A unit.
An 8 gauge supply wire would work to the relay and if you ran an individual wire to each lamp from the relay, 14 would be fine, however, if you want to do multiples of 2 then 12 gauge would be needed.
You can tie them all together using a #8 if you want.
If you use 2 relays, you can have the option of just having 2 lights on at a time.
Make sure you fuse the primary supply to the relay.
If you are going to add the other 2 lights later, you might want to consider running a 6 gauge wire instead to where the relays are mounted...that would give you enough for all and you would not have to mess around adding another wire at a later date.


That's how we roll!
What was said above...

I would use the 6 guage wire personally since you will have 6 lights. I like the option of being able to use 2 or 4 lights so the two relays is a good idea.


Tulsa, Ok
all wired up just waiting for the lights to come in. today or tmrw.

Btw i hate wiring.

and after i got it all wired up i went to test the accesorry end at the headache rack. no power. after going back over the wires at the relay and testing everthing with a test light and a multi meter. No power.

well i forgot to put the fuse back in where i tap the switch into.

Well i really didnt tap a switch in.

i dont use the cigarette lighter in the ashtray because i use the ashtray to hold change and crap..and a penny always falls in the open gap (i have no actual lighter (dad stole it)) and blows the fuse. so i snipped the positive plug off at the ashtray and ran it back up and drilled a hole in the dash piece where a 4x4 switch would normaly be and walla.