Novak Conversions Jeep Wrangler TJ radiator

Suggestions for wiring aftermarket lights

W

wcarson89

Member
Original poster
Supporting Member
Joined
Aug 4, 2019
Messages
40
Location
75238
I want to add some auxiliary lighting wire. Specifically I'd like to add one medium size light bar, a pair of yellow driving lights, and a pair of LED spot lights.

I'd like to use these types of switches for all three https://www.amazon.com/gp/product/B017282JQK/?tag=wranglerorg-20

What is the recommended way to wire all of this safely?


I'm decently capable and comfortable working with electrical - I've got a lot of car audio install experience - but I've never messed with relays.
 
A relay has a coil and a switch. When you apply power and ground to the relay coil, the switch will close. I would run 12v to Pins 86(coil) and 30(switch input) of the relay. Wire the dash switch to apply ground to pin 85(coil). Attach the lights to pin 87(switch output). Don't use pin 87a as this pin is in contact with pin 30 when the relay coil is not energized. It is useful for other things but not installing aftermarket lights.

I am sure someone will chime in with a wiring diagram but hopefully this helps you understand how a relay works.
 
  • Like
Reactions: wcarson89
80-image_fad59e5c8cbabaf41f3a726e9bf96a0382b0a9e9.png


Lighting manufacturers such as Rigid offer a harness and instructions on how to route the wiring.
 
  • Like
Reactions: TheYonderGod, Fonz54, wcarson89 and 1 other person
Thank you for the replies. This actually helps quite a lot. I would imagine three wiring harnesses (and 3 relays with fuses) would turn in to a potential rats nest quickly. Any advice on how to best approach this?
 
KC makes really good wiring harnesses as well for their own lights i've found. Good lengths, waterproof, relays/fuseable links included for reasonable price, etc. Just another option even if you go with another brand of light.
 
wcarson89 said:
Thank you for the replies. This actually helps quite a lot. I would imagine three wiring harnesses (and 3 relays with fuses) would turn in to a potential rats nest quickly. Any advice on how to best approach this?
Click to expand...
SPOD is one that I've seen and It's pricing, but looks really cool. There are some aftermarket voswitch I think on Amazon that do that same thing, 6 or 8 switches with a contained box with relays etc, but they are for the JK and have to do personal mods to make them work.

They have one made for the TJ is my understanding
https://www.4x4spod.com/

This is on Amazon, I read a guy did the work to make it fit a TJ (under hood bracket sounded like the biggest issue) and it's way cheaper (I don't have one, but sometimes you get what you pay for).
https://www.amazon.com/dp/B08H53GTFM/?tag=wranglerorg-20
 
Just take your time and carefully plan out the routing. Heat shrink and wire loom will keep everything from becoming a tangled mess.
 
  • Like
Reactions: ScottCO and Ephry73
Not a rats nest at all. The key phrase is 'daisy chain' (jumper wire). To control 3 switches you only need 1 wire daisy chained from the fuse box to each switch. Then 3 wires through the firewall to the relays (pin 86) for relay control. Relay control ground (pin 85) can also be daisy chained to ground. Main light power can be daisy chained to relays (pin 87). You would need to make sure the wire is large enough to handle the power of all 3 switches being on at the same time and a proper size fuse is added.

You can use these relays. They all connect together for a nice clean mounting setup.

https://www.amazon.com/dp/B017VDI0GY/?tag=wranglerorg-20

Here's a quick drawing

IMG_20200909_071302.jpg
 
  • Like
Reactions: wcarson89 and Ephry73
wcarson89 said:
Thank you for the replies. This actually helps quite a lot. I would imagine three wiring harnesses (and 3 relays with fuses) would turn in to a potential rats nest quickly. Any advice on how to best approach this?
Click to expand...

Like it was mentioned before, plan the routing of the wires to keep everything tangle free and neat as well as safe.

I went with an MCL-6 mostly because I will be adding other things, and I bought mine used at a decent price. Right now I have two switches going into the cabin and had to clean up the previous owner's lovely wiring and add new relays. The MCL6 has fuses and relays built in, as well as a kill-switch for the accessories if the battery level gets too low, which then leaves you stranded.

I will probably install this in the Fall, when I'm ready for the other upgrades I wanted to get done.

The MCl6 is not cheap, but it is also half the cost of the sPod. You can also customize your rockers for different names and devices.
 
CodaMan said:
Not a rats nest at all. The key phrase is 'daisy chain' (jumper wire). To control 3 switches you only need 1 wire daisy chained from the fuse box to each switch. Then 3 wires through the firewall to the relays (pin 86) for relay control. Relay control ground (pin 85) can also be daisy chained to ground. Main light power can be daisy chained to relays (pin 87). You would need to make sure the wire is large enough to handle the power of all 3 switches being on at the same time and a proper size fuse is added.

You can use these relays. They all connect together for a nice clean mounting setup.

https://www.amazon.com/dp/B017VDI0GY/?tag=wranglerorg-20

Here's a quick drawing

View attachment 188819
Click to expand...


Wow..this is super helpful - thank you. If I have a pair of lights such as fog lights do I need one relay for each light (i.e. two relays for the pair) or do I use one relay and split the wire from Pin 30 going to the lights?
 
  • Like
Reactions: CodaMan
1 relay per set.
Tricky part is figuring out what size fuse to use. The actual consumption of LEDs is way lower than regular bulbs.
Find that actual power consumption when you buy the lights, multiply by two and then use the formula (forgot off the top of my head) to determine the fuse size. If your number comes up as like 4.2 amps, use a 5 amp fuse. Round up to the next whole number.
 
wcarson89 said:
Wow..this is super helpful - thank you. If I have a pair of lights such as fog lights do I need one relay for each light (i.e. two relays for the pair) or do I use one relay and split the wire from Pin 30 going to the lights?
Click to expand...

1 relay per pair of lights and 1 relay per light bar.
 
Please remember that a fuses main purpose is to protect wiring not accessories. You need to have large enough wire to handle the power draw from the lights and a fuse small enough to to allow the fuse to blow before the wire melts or catches fire.
 
  • Like
Reactions: Ephry73

Similar threads

J
Blinker Genie Wiring - Front Marker Light Problems LED
Replies
2
Views
391
TJ General Discussion
jdalt9
J
Matt H
A couple electrical head scratchers…
Replies
4
Views
311
TJ General Discussion
Matt H
Matt H
ironraccoon
Need advice on wiring
Replies
7
Views
615
TJ General Discussion
JMT
JMT
StimpsonJCatt
Another A-Pillar Light Mount Install
Replies
4
Views
651
TJ General Discussion
StimpsonJCatt
StimpsonJCatt
DustyRhodes03
No signal or brake lights
Replies
2
Views
341
TJ General Discussion
DustyRhodes03
DustyRhodes03
Novak Conversions Jeep Wrangler TJ radiator
Top Bottom