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Weird electrical problem when trying to hook up LED tow lights

April 04, 2016, 05:15:50 pm

First of all, let me say that I have checked EVERYTHING at least 8 times!! Individually with a probe light, and  if necessary a battery charger.
Problem: When--and only when-- I hook up my 17" long Led lights (the same exact ones as I mounted on the coach) then the turn lights both left and right on the coach flash at the same time.
By itself, the coach lights and the LED lights I mounted on the rear of the coach work like they are supposed to. When I check the connector on the back of the coach (after the 5 to 4 converter) left, right, turn, run, & brake lights ALL work correctly on the coach & the Vue.
Connect up the Saturn Vue (equipped with 1157 bulbs) and coach and tow lights work correctly.
Plug in a little LED tester at the rear of the Vue  (where I planned on plugging in my LED light bar) and ALL lights, both coach and 1157 bulbs work correctly.
Plug in my LED light bar with two 17" Led lights and everything goes south!! Now all the turn lights on the coach flash when I put on the coach left turn signal. It doesn't happen when I turn on the right turn.
I checked AGAIN the tow light bar for about the 20th time. By itself--works fine.
What the devil is going on??

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Re: Weird electrical problem when trying to hook up LED tow lights

Reply #1 – April 04, 2016, 06:15:03 pm

NH,  Are the LED light bars mounted on the back of the Saturn?  And supposed to come on when you do what?  Are these just turn signals?  Do you have diodes in the Saturn to prevent feedback?

When Rance at Xtreme hooked up my LED tail lights and connected everything to the towing setup he put in a different flasher module and a different box for going from separate tail/brake and turn to combined tail/brake/turn that we have on the Jeep.

Mixing different light types with vastly different loads is a bit goofy. 

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Re: Weird electrical problem when trying to hook up LED tow lights

Reply #2 – April 04, 2016, 06:26:20 pm

Roger, the 1157 taillight bulbs and the 17" LED lights are totally independent from the Saturn Vue. The only thing they have in common with the Vue is that they are mounted on/in the Vue. LEDs bar is on top of the tailgate while 1157 bulbs are on sockets I mounted in the taillight housings. Totally separate wiring harness.
These lights indicate turn direction, braking, and running.
The Regular Vue brake lights and 3rd brake light are activated when the Readybrake cable activates the Vue's brake pedal.

Are you thinking maybe I should try removing the 1157 bulbs and see if that corrects my problem? Then there would only be LED lights on the towed wiring harness.

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Re: Weird electrical problem when trying to hook up LED tow lights

Reply #3 – April 04, 2016, 09:32:58 pm

I would try that. It might just be the combiner box.  My old one did not work when Rance started changing and adding LEDs on our coach.

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Re: Weird electrical problem when trying to hook up LED tow lights

Reply #4 – April 04, 2016, 10:32:52 pm

Roger, must be nice to be right all the time!! I did go out and bypassed the 1157 bulbs. LED light bars on the towed worked great!! And did not manifest flashing issue on the coach!!
I made a short jumper with a flat four that plugged into my curly Blue Ox cord so I could just plug in the light bar and not have the Vue "in the loop". Everything worked great!!
So I cut the ground wires going to the 1157 sockets and put bullet splices  in. Won't plug them together unless emergency happens--like someone "borrowing" the light bar permanently.
Now when I put on the brakes the LED light bars on the coach AND the Vue LED light bars light up, and include the Isuzu Impulse brake light, and if I brake enough to activate the Readybrake the Vue's tail lights and the 3rd brake light comes on also. Should be enough brake lights, don't you think?
Put on left turn signal the coach LED light bar, the Vue LED light bar, and the Isuzu Impulse amber turn signal light comes on. Same with right turn.
Running lites? All clearance lights are LEDs. The Isuzu tail lights are on, the 17" LED lights I mounted high up on the rear of the coach are on, and the Vue's 17" LED light bar is on. Should be enough, right??
Thank you so very much for your help. I was going just a "little bit" nuts trying to figure out what I had done wrong and I totally forgot about mixing technologies sometimes being a no no.

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Re: Weird electrical problem when trying to hook up LED tow lights

Reply #5 – April 04, 2016, 11:11:33 pm

Well I know I am not right all the time.  It just sounded like something I had seen before.  I am glad to have been helpful.  One of the best parts of this Forum is being able to help someone out.  I have been on the receiving end plenty of times and always happy to help in return.

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