I installed a side mount license plate holder (axle) on Saturday.

Background:
This side mount had 3 wires: red (brake), blue (run), and black (ground). I had previously installed the run/brake module so my turn signals would also act as brake lights. I am also running the stock tail light.

My Dilema:
To power the side mount (LED) i tapped into the red, blue and black wires after the run/brake/turn module but before the circuit board. My turn signals no longer work as run/brake/turn (but they do still function as turn signals). This strikes me as odd since those wires are brown and purple, which i didn't touch.

Anyone have an idea of what might have caused this? Since I'm still running the stock brake light the minimal draw for the LED's shouldn't have been an issue for the module, especially since I tied in on the downstream side of the module. Should I have tapped my power after the circuit board?

Thanks,
PT

 

When you say circuit board, do you mean the circuit board inside the tail light assembly?

 

When I installed mine I used the brown wire and the blue one. I would installe it after. I think you have it backwards. Let me do some looking tonight on mine and see what I have. I have the bandlands one but they should all be pretty much the same. I wrote out what each wire color was.

 

yes. I tied into the wires before they hit the circuit board inside the tail light.

 

so you're thinking I should've installed it after the circuit board?

 

They should all have their own wire. Find the original plate wire then re-route? Thats what i did and all is good.. Now, if your run light illumniates the plate then just tee off that wire for lighting.... I;m not sure what u mean by circuit board... Just find which wire is which some where between the harness connector and final destination... Helps if you have a volt/ohm meter and the service manual...

 

Joe - there is a wire bundle that connects to a circuit board behind the tail light. The circuit board sends the power to other connectors which then feed the lights.

the sequence of power is as follows
run/brake/turn module
wire bundle
circuit board
lights

I spliced into the wires after the run/brake/turn module before the circuit board

 

Yeah, the circuit board really isn’t a circuit board, meaning it doesn’t have any components on it, it’s more of a re-distribution board. Tapping off after the signal module or at the circuit board is the same thing, it’s just a straight wire. I think the issue must be that tapping off after the module is loading down the module and even though you tapped the tail/brake light wires and not the signal wires, the extra loading is effecting the signals. I don’t exactly know how the module is designed, but I got a pretty good idea, but however it’s designed, it sounds like there is an electrical relationship within the module between the tail/brake light circuit, which should just be a pass through circuit, and the modulated signaling circuit. It sound like you should tap before the module for your extra running light on your side mount plate. I would pull the black/ground splice to the new license plate light and see if the signal lights operate correctly, if yes, tap before the module. Of course, all this assumes you haven’t crossed the wires or caused any shorts with you splices.

 

I actually just had close to the same trouble. I pinched a wire and my lights would only work as turn signals. I tried every method of trouble shooting. I ended up getting a new module. Problem Solved. Must be the module fried when the wire was pinched.

 

did you get it to work yet? or did you have to send off for a new module?