bclexus

Absolutely no problem.

EAST

If it helps, a couple points from reading around.

The blind spot sensors are also the RCA sensors. The right hand sensor is the master and communicates with the left hand sensor, and the Network ECU via CAN Bus. The left hand sensor is the one that drives the speaker for RCA. The parking sensors don't come into play with the RCA system.
EDIT: Corrected the sides for which is master, right hand side is master.

Wiring changed somewhat from two connectors to one connector late 2013 so there is where your repining and possibly running new wiring would come in. EDIT2. After looking again, it seems things just changed from a 8 pin setup to a 10 pin setup. The 8 pin setup doesn't have a output for the RCA speaker so likely any 8 pin sensors don't support RCA.

But looking around at the eBay sensors, the "old" ones only have one connector, not two. So I'm not entirely sure where the second connector goes. The old style sensors appear to be 88162-0W010 for the right side and 88172-0W010 for the left side. These appear to have an 8 pin connector in eBay pictures. The ones used in late 2013 and later are 88162-0W140 for right hand. According to partsnext.com Lexus catalog, the LH sensor is also 88162-0W140 but it'd be good to confirm this. Either way, these newer sensors have a 10 pin connector.

​​​​​​If you're in messing around with your bumper one day, see if you can find the 8 pin and a 10 pin connector near by to each sensor. If possible notate the color of the wires for each pin.

You'll want to get the RCA sensor from the donor car as well.

Sorry if the post is a bit all over the place, I'm typing it up as I'm searching stuff. I'm really only looking because I wondered how hard it would be to have the RCA speaker also beep for blind spot alert. Since the left hand blind spot sensors seems to be the controller of it all, it would at least make any solution more centralized. But that's for another post if something comes of it...
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