Blind-spot warning beep without doors on

[l88m22vette]

I've been trying to research all the quirks and specific abilities of the Overland since getting it a few weeks ago, and just installed a set of Campsite Carbon mirrors for doors-off action. That said, we have the blind-spot warning system, but it shuts off when the doors are off. My wife really likes the audible beep, and I've been wondering if that's something that could be made to work either way.

It seems to boil down to if it is based on a connection being made in the door's wiring, or if its a code in a control module which controls both the mirror light and audio beep. I assume breaking a connection let's the CAN-Bus system know the doors are off, thus shutting off the system. That means the mirror indicator light is the primary notification function, with the audio beep being secondary (optional).

I was looking through electrical diagrams, and have to wonder if some kind of resistored jumper would work to allow the audio function even without the doors. The mirror light creates resistance, so wouldn't a matched resistor make the control module think the door is still there?

If you look at the blind-spot diagram, the taillight sensors ground to the mirror indicators at Z910 (right) and Z912 (left), which activates the mirror lights. The same connections are shown in the mirror exterior wiring PDF, but you can see secondary grounds, which makes me think that's for doors on, or doors off. The mirror interior specifically shows CAN-Bus connection between the door and BCM, so I think that'd be the connection that matters.

Basically, I can see the connections, and have messed around with wiring diagrams, pinning stuff, and the like. That was several years ago, though, and I'm rusty. I'm trying to figure out where the door harness connector is in these diagrams, I'd love to trace the mirror light's wiring and see what kind of power it is using.

These are the two things I could come up with:

1) use a jumper harness plug, or something similar, to make the BCM think the door is on; use a resistored connection, connect the ground the BCM expects to see from the door, etc.

2) find the blind-spot monitoring programming buried in the BCM/ECU, and see if there is a way to deal with it through JScan, Tazer, or the like.

Blind-spot diagram: https://www.jlwranglerforums.com/JL-Wiring-Diagrams/BLIND-SPOT-MONITOR-SYSTEM.pdf
Mirror exterior: https://www.jlwranglerforums.com/JL-Wiring-Diagrams/MIRROR---EXTERIOR.pdf
Mirror interior, CAN-Bus connection: https://www.jlwranglerforums.com/JL-Wiring-Diagrams/MIRROR---INTERIOR.pdf
Door wiring (passive entry): https://www.jlwranglerforums.com/JL-Wiring-Diagrams/LOCK-SYSTEM---PREMIUM.pdf

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[sharpsicle]

Doesn't the truck do more than just disable the BSM when the doors are off? I don't think it would be a good idea to trick it into thinking they're still on. Even if you did, it would instead think they're always open then and you'd go nowhere. And the monitoring system probably still wouldn't work. With this type of system, it likely isn't enough just to trick the system into thinking something is there, it's going to be trying to use it, and when it can't it'll throw a fault. And based on your description of the system, the mirror is a central part of it, so without it you've removed a component.

This all kind of means both your options aren't readily feasible. Sounds to me like the only way to get it back is to have the mirrors back on. Yeah it would've been nice if Jeep designed it in a way where you could get what you're looking for, but if that were the case I doubt they would've just defaulted to disabling it if it could still function. I think this is just the limit you hit here short of designing a new mirror or bypass cable to plug in that can effectively enough mimic the mirror's BSM operation without making the truck think the door is still on. But that's a trick too since it makes a number of changes when it detects the doors are removed.

Not saying it's not possible, but since you're dealing with trying to change the operation and deal with some safety-related programming in the BCM, it's likely not to be as easy as you think.