Attached are appropriate wiring diagrams for the complete BSM system/entire vehicle connector layout. You can see the wire colors, pin numbers, and match them up to what is/is not present on your vehicle.Yes, you will need this jumper. I looked at this again this morning to refresh my memory. That jumper will get the correct connections to the body harness. I have that. However, the body harness - again on my 2018 Sahara - does not have the wires that run to the star hub. There is no part number for this - other than a new body harness. You will need wires and correct plug type. There is a third misssing wire - the one that turns on the indicator. Again correct harnesses for mirror, door, will get that connection to body harness, but you will need to run that wire back to the taillight harness. It seems that Jscan has hit all the appropriate config settings. I’ll try connecting the two harnesses I made to from the star hub to taillights and see what happens. But that probably won’t be today.
Pins 10 and 11 on either taillight harness need to be run to the IHS STAR bus located inside vehicle over right rear fender. Wires are NOT present on most non-BSM equipped vehicles. All? Don't know. Build specs change - my 2018 Sahara and another 2018 Rubicon - NOT present. Therefore, you will need appropriate connector and wire. I would not just splice into another IHS bus connection. The connectors connect to port C2 and C3 on the IHS bus hub.
Pin 12 turns on the indicator light and must be run to the L/R door harness, and tap into the DOOR SIDE, as the wire will NOT be present on most JLs. Connector XY600A. X or Y designates body side or door side. I believe X is door side, Y is body side. Don't hold me to that. Obviously one will be male and one female. Make sure you are looking at the correct one and correct pin to verify if wires are present.
Pin 9 is for relay control - this must be run to connector XY401A and to a relay in the power distribution center.
The turn signal circuit mirror indicator, while shown, is not present in US spec JLs. It just feeds back to the turn signal control, which is part of the BSM operation. The turn signal control is relevant, regardless of the presence of the mirror turn signal.
These were SVG diagrams I converted to PNG to be uploaded.
You would need to buy a subscription to Tech Authority (FCA), $26.95 for 24 hours. It goes up from there. SVG files are then interactive if logged into site, you can click on a connector to see more info, pinout etc.
At this point, I'm probably done with this. I'll be putting up radar modules and taillight harnesses up for sale. Passive entry was one thing, this is another animal.