Wiring Lightbar to Highbeams Question

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Alpine4x4

Junior Member
Joined
Mar 2, 2020
Posts
4
Reaction score
0
Location
Washington
Ram Year
2012
Engine
6.7 Cummins
So I have my light bar wired to a SPDT switch so I can have the option of light bar on, light bar off, light bar on with highbeams. I have used a 9005 extension between the factory plug and my LED high beam bulb and spliced into the positive lead on it for a trigger to the switch. The switch has a trigger wire run to a relay that powers the light bar. Everything works as intended when it is all wired up, except whenever I switch the high beams on with the light bar activated by the switch, I get a small pop from the TIPM like a short and the fan on my LED headlight ramps up like there is an extra load on the system. I get no bulb out message and all the lights work as intended. The pop from the TIPM has me worried I will short it out or that something is possibly back feeding into the headlight circuit? Anyone have any insight? Truck is a 2012 Ram 3500 Laramie.
 

Kalill Nieto

Senior Member
Joined
Jan 28, 2018
Posts
314
Reaction score
102
Location
Fort Lauderdale
Ram Year
2017
Engine
Hemi 5.7
I do almost the same with my light bar. In my case was a little different because mine has 2 colors and the light bar work with positive comun. One ground for each color, so in my case I use a relay that I put in the line to make it work with the high beam signal and send ground to the light bar, that way is safe too to the car circuit. In my case I connect 85 and 86 to the high beam wires, 30 to the light side 87a to the module that send negative, that way I can still use the remote control that work with that module and 87 to ground. In your case you can do this 85 and 86 to the high beam wires, cut the positive wire of the light bar, 30 to the light bar 87a to the switch side or actual harness and 87 to the battery positive. Hope this help.
 

SitKneelBend

Senior Member
Joined
Jan 8, 2015
Posts
9,022
Reaction score
4,694
Location
St. Louis
Ram Year
2014
Engine
3.6 Pentastar
I had the same problem a long time ago. I don't remember exactly but I believe the problem is at the switch. There are too many wires plugged in. Can you take a picture of the switch you are using with the wires you're running to it?

Sent from my HTC U11 using Tapatalk
 
OP
OP
A

Alpine4x4

Junior Member
Joined
Mar 2, 2020
Posts
4
Reaction score
0
Location
Washington
Ram Year
2012
Engine
6.7 Cummins
I had the same problem a long time ago. I don't remember exactly but I believe the problem is at the switch. There are too many wires plugged in. Can you take a picture of the switch you are using with the wires you're running to it?

Sent from my HTC U11 using Tapatalk
These switches here. Only 3 prongs to plug into. Wires going to it are a hot 12v, high beam wire, then the trigger wire for the relay. 12v on an outside prong, trigger in the middle, high beam on the other outside.

https://www.ebay.com/itm/10x-ON-OFF-ON-3-Position-SPDT-Round-Rocker-Switch-10A-125V-6A-250V/152201306705?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649
 

JB1

Senior Member
TOTM Winner
Joined
Nov 3, 2011
Posts
8,366
Reaction score
7,527
Location
Houston, Texas
Ram Year
2017
Engine
Hemi 5.7
OP
OP
A

Alpine4x4

Junior Member
Joined
Mar 2, 2020
Posts
4
Reaction score
0
Location
Washington
Ram Year
2012
Engine
6.7 Cummins
Sounds like you need to add a diode on one of the power source's so you dont get any back feed.

I have a couple things dual wired on my truck and used the HD diodes below and they work great.

https://www.amazon.com/Roadmaster-7...master+792&qid=1585353286&s=automotive&sr=1-1

https://www.amazon.com/gp/product/B01CXOQMJ8/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1
Thats what I was wondering was if I was getting back feed. I wouldnt think so since on the high beam setting the switch is only seeing power in from the high beam wire and power out through the trigger wire. The 12v in should be isolated, but maybe not.
 

SitKneelBend

Senior Member
Joined
Jan 8, 2015
Posts
9,022
Reaction score
4,694
Location
St. Louis
Ram Year
2014
Engine
3.6 Pentastar
Thats what I was wondering was if I was getting back feed. I wouldnt think so since on the high beam setting the switch is only seeing power in from the high beam wire and power out through the trigger wire. The 12v in should be isolated, but maybe not.
I literally had this exact problem. It was at the switch. I put an inline fuse on mine though so the pop was the fuse going.


Sent from my HTC U11 using Tapatalk
 
OP
OP
A

Alpine4x4

Junior Member
Joined
Mar 2, 2020
Posts
4
Reaction score
0
Location
Washington
Ram Year
2012
Engine
6.7 Cummins
So reviewing my wiring the only thing I can come up with is adding a diode.

Positive from the battery and the 12v hot for the switch come from the same spot on the relay, trigger wire goes into its own spot, hot out goes to the light bar on its own spot, , ground from lightbar goes to its own spot which also has a lead to the battery ground. Positive lead from the high beam goes into the 3rd port on the switch. I cant see anything wrong with it.
 
Top