I have re-wired two JK's so that I could run the license plate and integrated third brake light (rather than the factory) without issue. Today I wanted to finalize the installation of a rear bumper with tire carrier by installing an integrated third brake light and license plate light.
I have the license plate bracket all wired up, with both ground wires for the brake and license plate lights tied together and then I have a second and third wire, one each for the brake and license plate. I joined them using a three wire connector (weatherproof) so that the bracket can be removed if necessary to get to the spare. I tested my wiring to the license plate/brake light bracket using a 12 volt supply and with a common ground, each remaining wire lights up one of the lights, so far so good.
I then ran the three wire cabling from the mounted spare in a nylon sheath across the tire carrier and over to the passenger side brake light. I pulled the wiring bundle in its sheath from under the body to the hole for the wiring for the passenger side rear tail light. I unscrewed the tail light from the body and found three wires along with the light being grounded by the body. I then bared a portion of each of the three wires on the factory light wire harness and go about testing to see which one is brake, turn signal, reverse, and tail light. Regardless of what I do, I cannot get my add-on lights to light up when using any of the three factory wires. (yes, I have everything grounded). What am I missing? I need the license plate light to illuminate with the tail lights, and obviously the third brake light to light up with the brake lights.
I'm about to dig into the electrical schematics in the Service Manual, but thought I ask the wisdom of the group too.
Also, I noticed that the drivers side tail light has a connector to unplug from the wiring harness, but the passenger side appears to be hard wired, unless the connector is hidden somewhere up in the rear fender.
PS. I also wired in a backup camera today (inside the trailer hitch receiver) and needed to connect a wire on the drivers side to the backup (reverse) light. I think I did it correctly, but pending understanding of the tail light wiring setup, I guess I'm not certain.
I have the license plate bracket all wired up, with both ground wires for the brake and license plate lights tied together and then I have a second and third wire, one each for the brake and license plate. I joined them using a three wire connector (weatherproof) so that the bracket can be removed if necessary to get to the spare. I tested my wiring to the license plate/brake light bracket using a 12 volt supply and with a common ground, each remaining wire lights up one of the lights, so far so good.
I then ran the three wire cabling from the mounted spare in a nylon sheath across the tire carrier and over to the passenger side brake light. I pulled the wiring bundle in its sheath from under the body to the hole for the wiring for the passenger side rear tail light. I unscrewed the tail light from the body and found three wires along with the light being grounded by the body. I then bared a portion of each of the three wires on the factory light wire harness and go about testing to see which one is brake, turn signal, reverse, and tail light. Regardless of what I do, I cannot get my add-on lights to light up when using any of the three factory wires. (yes, I have everything grounded). What am I missing? I need the license plate light to illuminate with the tail lights, and obviously the third brake light to light up with the brake lights.
I'm about to dig into the electrical schematics in the Service Manual, but thought I ask the wisdom of the group too.
Also, I noticed that the drivers side tail light has a connector to unplug from the wiring harness, but the passenger side appears to be hard wired, unless the connector is hidden somewhere up in the rear fender.
PS. I also wired in a backup camera today (inside the trailer hitch receiver) and needed to connect a wire on the drivers side to the backup (reverse) light. I think I did it correctly, but pending understanding of the tail light wiring setup, I guess I'm not certain.
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