Installing some back up lights flush into my Fab Four rear bumper which is at powder coater now. Was going to get wires run while bumper is off. I was planning on hooking into reverse lights and installing a separate switch also. Here is what I bought:
Wires "A" and "B" are pretty straight forward. After that, I am not sure.
Is "D" where I tap into trailer harness reverse light? I guess "C" can be tapped into trailer harness ground also?
So "E" goes to junction connector then to switch? "F" would be a ground but "G" I would tap into acc power?
The upper left has the diagram for the switch and it seems pretty straight forward - "I" to "Source" on switch, "J" to "Relay" on switch, "H" to "Upper" and" Lower" ground, and "6" on switch I would tap into powered line that comes on when interior dash lights come on?
Does this sound about right? What is a good source for "G" on junction and for "6" on switch?
You would want to have the turn on terminal on the realay attached to the switch. However, if you also want them to come on in reverse you would have to have a diode to prevent the voltage from either source feeding the other point. You don't really want power coming back to the switch from the trucks reverse signal, and you definitely don't want the switch power going through the reverse circuit to the truck. I can only assume this could really fub up some electrical magic ecu on the truck.
I believe terminal 86 on a relay is the activation terminal. 87 should be output to lights, 30 should be power source wire attached to battery +, and 85 is ground for the relay.
You could probably just use the trailer reverse signal direct to the output wire, just as stated you should install a diode to prevent power from going back through the truck's circuit when the switch is on. This way I don't think you would need a second diode to protect the switch from backfeed as the relay would be off unless you had the switch on at the same time.
I just used the reverse lead in the trailer harness. It is already capable of feeding led's. I just made a plug to plug into the trailer plug though as my lights are on my hitch hook/anti ass-pack hitch I made.
I thought originally I wanted a switch inline so I could turn them on whenever I wanted to, but decided that I really didn't/don't need to turn them on often enough do do this as of now.
using 2 relays you can wire the whole thing from the trailer harness if you have one with a single 12V trigger from the dash, I just did this a few weeks ago. Relays would be at the trailer harness near the spare.
Reverse Lights with switch:
Relay 1
(87) 12v (from Trailer harness)
(86) reverse wire in harness (85) Ground in harness
(30) to relay 2 pin 87a
Relay 2
(87) 12v (from trailer harness)
(86) 12v trigger from switch (87A) from Relay 1 pin 30 (85) Ground
(30) too new lights +
This allows the new lights to come on with either the switch or when in reverse with no isolation diode needed, PM me if you need more info
using 2 relays you can wire the whole thing from the trailer harness if you have one with a single 12V trigger from the dash, I just did this a few weeks ago. Relays would be at the trailer harness near the spare.
Reverse Lights with switch:
Relay 1
(87) 12v (from Trailer harness)
(86) reverse wire in harness (85) Ground in harness
(30) to relay 2 pin 87a
Relay 2
(87) 12v (from trailer harness)
(86) 12v trigger from switch(87A) from Relay 1 pin 30(85) Ground
(30) too new lights +
This allows the new lights to come on with either the switch or when in reverse with no isolation diode needed, PM me if you need more info
Let me look at those and i'll comment in a second but this I can vouch for 100%, feel free to call me tomorrow I'll walk you through it, PM me if you want my #. I'll be playing truck (that's what my wife calls it) all day tomorrow anyway.
Again this will trigger the new lights when in reverse and also with an aux switch with no isolation diode needed.
If you will be putting the relays outside the truck, I would highly recommend a high quality waterproof relay. These usually come with a higher price tag.
In the years of electrical farkles I put on our sport touring bike, I only had one failure and that was a inexpensive relay that came with the aftermarket horn. When it died, I replaced it with a name brand unit and never had an issue with it after that. Any moisture getting in the relay will cause it to fail in short time.
Marine grade relays are some of the best, as long as they are reputable brands, but they are expensive.
Can those be bought at auto stores? Seems like most of the shit at autozone, shucks, and whatever other stores are just made up Chinese garbage brands.
Thanks but that diagram will only allow the newly installed lights to come on when the vehicle is in reverse. It will not give you the ability to turn the reverse lights on in any other situation and isolate the reverse light circuit
Anybody know where the trailer harness actually grounds? I'm having trouble with mine and need it fixed before I can do these bumper lights
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