"If I can do It You Can" Behind Grill Light Bar Install

[Cymon]

Thanks to everyone for posting all of the LED and switch information in all the threads that are linked through this one. I would like to get clarification from you on the diagram below. Based on all the feedback... It appears that this represents the correct schematic for using a OPT7 22inch LED and an AOB switch. I do have three questions as outlined in the yellow boxes too. So my questions:
1) Is this schematic correct?
2) Do I need to add a 3A fuse between the OPT7 relay and the AOB switch? Should I anyway?
3) The 30A fuse that comes with the OPT7 harness seems excessive for the overall wattage of the 22" LED light bar. Should this be reduced to 15A or 20A? What have others done?
4) Most importantly... I'm thinking that I should wire up the dimming light to the Wiper Warmer switch first. Verify that the dimming light works just to ensure that I don't accidentally cross-wire or even touch the HOT 12V to the ground. Thoughts?

(FYI... once I get some feedback, I'll edit this post to have an "final" schematic.)

Thanks.

1) Looks correct to me, that's how I did it here.
2) No, you don't need the fuse there, although you could add one if you really wanted. From how [MENTION=83083]rigtec[/MENTION] explained it to me in his opt 7 thread that I'll link again here, you would want a diode or fuse if you were integrating into other vehicle systems like the high beams.
3) As far as I know having an over rated fuse is safer. I have had no issues so far with the harness as is. (Edit: You don't want higher fuse so that it does blow)
4) That is exactly what I did and think it is a good plan. The switch worked on the dimmer without the opt7 harness attached so it is a good test (and confidence booster).

Hope this helps! Good Luck with the install, and if you have further questions post or pm me.

Oh the Link I promised...
http://www.toyota-4runner.org/5th-gen-t4rs/178040-opt7-leds-6.html

 

[rdswriter]

Thanks for the responses, but I have to disagree on #3 based on my understanding. of circuits. The higher the amperage fuse... the more likely it is to NOT fail in the event of wires heating up. That being said, if the OPT7 wires and relay are all sufficient enough to handle 30A... then it won't matter. And if no one else is lowering the fuse amperage, then I will leave it alone.

What slightly concerns me if you get more than a 3A pull for some reason to the switch. In that event the switch would burnout/fail rather than an additional inline 3A fuse... but I don't know if that is even possible via the relay. I don't really have any experienced with relays... can they even provide that much amperage to via switch feed wire? My gut is telling me that I'm overthinking this and I should just leave the OPT7 fuse/relay intact 'as is'.

 

[Cymon]

Thanks for the responses, but I have to disagree on #3 based on my understanding. of circuits. The higher the amperage fuse... the more likely it is to NOT fail in the event of wires heating up. That being said, if the OPT7 wires and relay are all sufficient enough to handle 30A... then it won't matter. And if no one else is lowering the fuse amperage, then I will leave it alone.

What slightly concerns me if you get more than a 3A pull for some reason to the switch. In that event the switch would burnout/fail rather than an additional inline 3A fuse... but I don't know if that is even possible via the relay. I don't really have any experienced with relays... can they even provide that much amperage to via switch feed wire? My gut is telling me that I'm overthinking this and I should just leave the OPT7 fuse/relay intact 'as is'.

On #3 that was what I was trying to say, you just put it in more correct terminology then I did. As for your gut telling you you're overthinking...:iagree:

 

[Saker]

I don't have an OPT7 light setup, but I did reduce the fuse size to 15 10 Amps from the power source to the relay just to protect the system in the event that something would go haywire. I figured for my 120watt LED LIGHT BAR 120W/12V = 10A

 

[Cymon]

[MENTION=103267]Saker[/MENTION] is correct in his statement...I was completely backwards and incorrect on the answer I gave above and mentioned so in an edit in the post. Although I will be sticking with the 30amp fuse as I don't have any plans to change it out and it is what the company sent with the relay made for this light bar...so I'm just "trusting" that it works.

 

[RysiuM]

I have 28 inch 140W (plus minus) light bar that came with 40A relay and 30A fuse (I think the harness is standard for all bars). I will be changing fuse to 20A. My lamp takes 10A or so, so any fuse that will not blow under normal working condition is fine - the smaller the better. Smaller fuse will protect from "semi-short" better - for example wire with broken or rubbed-off insulation. What 30A might still hold on such wire damage the semi- short point will heat up with up to 360W minus your lamp wattage, while 15A fuse will blow when the semi-short will start heating up with way less than that.

So the bottom line is: the smaller fuse, the better protection. The lower limit is amperage under normal condition plus same margin.

If you are connecting your +12V switch to one of 10A fused circuits the second in line fuse (3A fuse) it is probably overkill. If you are tapping straight to battery or higher amperage fuse circuits (like headlights for example) you should use additional lower amperage fuse (probably 10A or less).

EDIT: I don't have OPT7 harness diagram, but from reading it looks like OPT white gets +12V from the battery via 30A fuse. If it is true, I think it is a lot for this poor AOB switch.

 

[Deuskid]

awesome thread and a mod I want to do someday.

 

[Cymon]

awesome thread and a mod I want to do someday.

Thank you!:hatsoff:

 

[9646gt]

That looks awesome

 

[HoustonT4R]

Summary:
This install did not go as smoothly as my last couple of mods (Rear differential Breather & AOB Switch), but I learned a lot with this one. Hopefully I have shown that anyone can do this mod if they really want to. The total net $ of this project including the light bar was under $200, which even impressed my wife. This will likely be the last mod for a while (don’t you love when everyone on here says that LOL!), unless there are some awesome group buys on armor in the near future and I can get my accountant to release the funds. I can’t wait to try this one out on some canal roads in the Everglades!

Oh, and beer of choice for this install…Lagunitas Litte Sumpin’ Sumpin’ Ale…my personal go-to!

Exactly what i need. thank you broda :target:

 

[ravenrunner]

Awesome, thanks for this. So many great write ups on this forum!

 

[Simonpk]

another way - go to teal supermarket or similar and for about $15 ask for 2 pieces of aluminum rectangular tube - 4" high by 2" wide and 1.5 or 2" long - drill, tape and bolt to your bumper bar - exactly teh right height for grille led bar -see photos

 

[Simonpk]

meant Metal Supermarket!

 

[RockyMtnRunnr]

Thanks for putting this together! Been wanting to do this for a while and excited to get going.