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-   -   Auxiliary Reverse Lights - Advice & Guidance Needed (http://www.wranglerforum.com/f282/auxiliary-reverse-lights-advice-and-guidance-needed-234063.html)

PStov98TJ 04-09-2013 12:00 PM

Auxiliary Reverse Lights - Advice & Guidance Needed
 
So I’ve been doing some research on how to properly wire in two auxiliary reverse lights and I think I’ve got the idea, or at least somewhat of an idea. I want these lights to come on automatically when I put the jeep in reverse but also to come on when ever I need them to without having to turn the key in the ignition. But to make sure I understand this correctly….

I will need:
1) A SPDT switch (I was thinking just a 2 way one, but might still go 3 way if someone convinces me other wise)

2) A relay. Do I need one that has 5 leads or just 4 leads? (To clarify, do I need one that has the 30, 85, 86, 87, and 87a ports on it or one with just the first 4 listed? Is that the difference between a SPST and SPDT relay?)

3) Diodes to protect the OEM wires

4) 2 inline fuses

5) Connectors for splicing and connecting wires to relays and 12gauge wire



As far as I understand it, this is how I will need to wire it using the 4 lead relay:
1) Wire from positive battery terminal with 10amp inline fuse to the top “prong” on switch.

2) Wire from middle prong on switch, through an inline diode, to the 85 slot on the relay then from the 86 slot to a ground.

3) Wire from factory reverse switch to bottom prong on switch with inline fuse. (Do I need a diode here as well?)

4) Wire from positive battery terminal to 30 on the relay.

5) Then finally a wire from 87 to the new lights with appropriate grounds for the lights.

If I’m not mistaken, with this setup using a 2-way switch, when the switch is in the up position the lights will be on regardless of the OEM reverse lights. And when the switch is in the down position, the lights will come on only when the stock reverse switch energizes the relay sending power to the new auxiliary lights. And obviously with a 3-way switch it would operate the exact same way except with the lights never coming on when the switch is in the middle position.



And here come the dumb questions…
1) I have some KC long-range lights already mounted that you can probably see…but my friend’s uncle wired them in for me when I first got the jeep when I had barely turned 15… :hide: So how do I access the panel to the left of the cig lighter to put a new switch in? Do I have to remove the dash?

2) Where is the best place to tap the reverse switch? At the rear light or down on the tranny?

3) Where is the best place to put the relay? Up front by the battery or in the rear of the body by the taillight housing?

Extra thanks for those who read the whole post and for any and all help answering my questions and correcting any mistakes I may have made! :thumb:

OhSixTJ 04-09-2013 12:07 PM

A relay with 2 87 posts, not the 87a. A switch with just on/off.

Tap into the reverse light wire for a trigger wire and tie it with the power from the switch onto the trigger post of the relay. Then wire lights and relay like normal.

No diodes needed.

PStov98TJ 04-09-2013 12:13 PM

Quote:

Originally Posted by OhSixTJ (Post 3614146)
A relay with 2 87 posts, not the 87a. A switch with just on/off.

Tap into the reverse light wire for a trigger wire and tie it with the power from the switch onto the trigger post of the relay. Then wire lights and relay like normal.

No diodes needed.

So one with two 87 posts... I run one wire from the switch to one 87 post and one spliced wire to the other 87 post correct? Then theres just one out for both of those posts right? Are there any wires running to the 85 or 86 post to energize the coil?

Sorry, you're gonna have to put this in idiot proof terms

OhSixTJ 04-09-2013 12:54 PM

Quote:

Originally Posted by PStov98TJ (Post 3614172)

So one with two 87 posts... I run one wire from the switch to one 87 post and one spliced wire to the other 87 post correct? Then theres just one out for both of those posts right? Are there any wires running to the 85 or 86 post to energize the coil?

Sorry, you're gonna have to put this in idiot proof terms

The 87 posts are for the lights. 30 is for main battery power, 85 is ground, 86 is the switch you want and the wire tapped into the reverse light hot wire.

Connected like this, the lights come on in reverse and whenever you throw the switch.

PStov98TJ 04-09-2013 01:05 PM

Quote:

Originally Posted by OhSixTJ (Post 3614340)

The 87 posts are for the lights. 30 is for main battery power, 85 is ground, 86 is the switch you want and the wire tapped into the reverse light hot wire.

Connected like this, the lights come on in reverse and whenever you throw the switch.

Ok. So I understand the ground on 85 and power to 30. And I think I understand the rest now.
So a spliced wire from the reverse switch is run to 86 post to energize the relay when I put it in reverse thus sending power to the rear fogs correct? Then the wire from the out post on the switch will go to the 87 post correct?
My one other question is that, are there 5 slots on the relay and only 4 posts? Or vice versa?
Thanks for your help!!

Jerry Bransford 04-09-2013 01:06 PM

I wired my aux backup light relay so it could be triggered either of two ways... 1) By shifting iinto Reverse so the Reverse +12v would trigger the relay. 2) Using a hard-wired source of +12v you add so you can also turn the lights on via that SPDT switch mounted next to the light without needing to shift into reverse. I used a SPDT switch for that.

The SPDT switch's center connector goes to the relay's control circuit, the switch's 2nd outside lug goes to the always hot +12v source I added, and the switch's 3rd outside lug connected to the normal Reverse wire.

That SPDT (single pole double throw) switch is simply used to select between two possible ways of turning the aux backup light on... by just turning the light on via the SPDT switch, or using the transmission's Reverse switch to turn it on when the SPDT switch is in its other position.

OhSixTJ 04-09-2013 01:13 PM

Quote:

Originally Posted by PStov98TJ (Post 3614383)

Ok. So I understand the ground on 85 and power to 30. And I think I understand the rest now.
So a spliced wire from the reverse switch is run to 86 post to energize the relay when I put it in reverse thus sending power to the rear fogs correct? Then the wire from the out post on the switch will go to the 87 post correct?
My one other question is that, are there 5 slots on the relay and only 4 posts? Or vice versa?
Thanks for your help!!

No. The wire from the switch goes to 86 also. The relay only needs a few amps to trigger so don't worry about having 2 "hot" sources on the 86 post.

87 go to one light each. Unless you have a relay with 87a or a 4 post relay. For 4 post or 87a relays you must connect both lights to the "87" post.

Power to the 86 post that tells the relay to send power to both 87s. Simple enough?

PStov98TJ 04-09-2013 02:29 PM

Quote:

Originally Posted by Jerry Bransford (Post 3614388)
I wired my aux backup light relay so it could be triggered either of two ways... 1) By shifting iinto Reverse so the Reverse +12v would trigger the relay. 2) Using a hard-wired source of +12v you add so you can also turn the lights on via that SPDT switch mounted next to the light without needing to shift into reverse. I used a SPDT switch for that.

The SPDT switch's center connector goes to the relay's control circuit, the switch's 2nd outside lug goes to the always hot +12v source I added, and the switch's 3rd outside lug connected to the normal Reverse wire.

That SPDT (single pole double throw) switch is simply used to select between two possible ways of turning the aux backup light on... by just turning the light on via the SPDT switch, or using the transmission's Reverse switch to turn it on when the SPDT switch is in its other position.

Ok, a few questions:
What is a good spdt switch I can get?
Can the hard power source be a direct wire from the batter with an inline fuse?
What do you mean by "center" and "outside" connectors on the switch?
And what post would these wires go to on a relay?
Sorry for all the questions at once. I understand that concept of a relay but I'm just a little confused on the terminology. Thanks for the help!

P.S. would the other method work also so that both sets of lights come on with the switch in one position and only the fogs in the other?

Jerry Bransford 04-09-2013 02:33 PM

1 Attachment(s)
Quote:

Originally Posted by PStov98TJ (Post 3614732)
Ok, a few questions:
What is a good spdt switch I can get?
Can the hard power source be a direct wire from the batter with an inline fuse?
What do you mean by "center" and "outside" connectors on the switch?
And what post would these wires go to on a relay?
Sorry for all the questions at once. I understand that concept of a relay but I'm just a little confused on the terminology. Thanks for the help!

Most any electronics supply store like Fry's or Radio Shack carries SPDT (single pole double throw) switches. Just avoid the smaller miniature SPDT switches & it should be fine.

Yes just a direct fused wire from the battery will be fine.

A SPDT switch has 3 connector lugs. The switch switches the center connector lug between the other two outside connector lugs.

This type of SPDT switch would be a good one to use... you need one with a center-off position.

PStov98TJ 04-09-2013 02:37 PM

Quote:

Originally Posted by OhSixTJ (Post 3614414)

No. The wire from the switch goes to 86 also. The relay only needs a few amps to trigger so don't worry about having 2 "hot" sources on the 86 post.

87 go to one light each. Unless you have a relay with 87a or a 4 post relay. For 4 post or 87a relays you must connect both lights to the "87" post.

Power to the 86 post that tells the relay to send power to both 87s. Simple enough?

So you're saying a switch a simple SPST switch with just ON/OFF functions.
A wired from battery to switch.
A wire from middle post of switch to post 86 on relay. Also a spliced wire from the reverse lights to relay post 86.
Then relay post 85 to ground.
Then outgoing wires from the 87's to each light.
Is that correct? I'm sorry for seeming so uneducated on this. I know it's a very simple concept. I promise I really did my homework before I posted. Haha just still trying to learn it.

PStov98TJ 04-09-2013 02:50 PM

Quote:

Originally Posted by Jerry Bransford (Post 3614750)
Most any electronics supply store like Fry's or Radio Shack carries SPDT (single pole double throw) switches. Just avoid the smaller miniature SPDT switches & it should be fine.

Yes just a direct fused wire from the battery will be fine.

A SPDT switch has 3 connector lugs. The switch switches the center connector lug between the other two outside connector lugs.

Awesome. That makes perfect sense.
And for the relay, what type?
And as far as the set up goes, the reverse wire will trigger the relay and turn on all 4 reverse lights when I put it in reverse and the switch is in the down position correct?
Then a wire from the battery to 30 post on the relay?
Then the out going wire from the switch will go on post 86 so that it can also manually/automatically trigger the relay depending upon what position the switch is in correct?

OhSixTJ 04-09-2013 09:30 PM

Quote:

Originally Posted by PStov98TJ (Post 3614831)

Awesome. That makes perfect sense.
And for the relay, what type?
And as far as the set up goes, the reverse wire will trigger the relay and turn on all 4 reverse lights when I put it in reverse and the switch is in the down position correct?
Then a wire from the battery to 30 post on the relay?
Then the out going wire from the switch will go on post 86 so that it can also manually/automatically trigger the relay depending upon what position the switch is in correct?

Right. When you put it in reverse, all 4 (2 stock, 2 you just added) will light up if you tapped into the reverse wire and connected that to 86. The switch you ALSO connect to 86 will only light the 2 you added. Well actually, I don't think it will back feed to the stock reverse light. Trial and error haha

PStov98TJ 04-09-2013 11:03 PM

Quote:

Originally Posted by OhSixTJ (Post 3616946)
Right. When you put it in reverse, all 4 (2 stock, 2 you just added) will light up if you tapped into the reverse wire and connected that to 86. The switch you ALSO connect to 86 will only light the 2 you added. Well actually, I don't think it will back feed to the stock reverse light. Trial and error haha

Well the back feeding can be stopped by adding a simple 1A diode on the wire that was spliced from the reverse switch so that's no problem. Thanks so much for your help man! Saved me hours trying to figure this out in a hot garage here in Mississippi when I get home from school.
I'll probably do a write up on this once I get it all done this summer. Hopefully it comes out well!
But one more question, where would you put the relay for this if it was your jeep?

OhSixTJ 04-10-2013 12:10 AM

Quote:

Originally Posted by PStov98TJ (Post 3617374)

Well the back feeding can be stopped by adding a simple 1A diode on the wire that was spliced from the reverse switch so that's no problem. Thanks so much for your help man! Saved me hours trying to figure this out in a hot garage here in Mississippi when I get home from school.
I'll probably do a write up on this once I get it all done this summer. Hopefully it comes out well!
But one more question, where would you put the relay for this if it was your jeep?

Glad I could help. I'd hide it in the back somewhere. Behind the bumper or something. Less wires to run than if you mount it up front.

gsellars 09-14-2013 12:17 AM

one of you want to do a complete write up with pics of this? and a parts list?

adolfsonzp 09-14-2013 12:49 AM

I used a SPDT switch for that. http://digitalso.com/9i.jpg

Atthehop 09-14-2013 05:42 AM

Basic Relay Wiring
 
1 Attachment(s)
Here is the basic wiring setup for a relay.

gsellars 09-14-2013 06:45 AM

Okay. Not that electrically savy at this time....no easy step by step write up somewhere?

PStov98TJ 09-14-2013 10:06 PM

Quote:

Originally Posted by gsellars (Post 4560841)
Okay. Not that electrically savy at this time....no easy step by step write up somewhere?

I haven't found one. And this mod has moved far down my todo list to be honest. But if I get bored between mods, I might do it and do a write up on it.

Water Dog 09-14-2013 11:09 PM

Quote:

Originally Posted by PStov98TJ (Post 4580697)
I haven't found one. And this mod has moved far down my todo list to be honest. But if I get bored between mods, I might do it and do a write up on it.

I've got a schematic drawn of just what you want to do, but it's on my home computer and I'm traveling this next week so I can't access it til about a week from tomorrow. If you still have a need for something then, shoot me a PM, and I can e-mail it to you.


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