Audi LinBus B9 S4 Seats

Projects General Guidance
1

I am trying to get the lumbar support to work on my seats from a 2018 Audi S4. I installed them on a 2007 A3.

I got a bcm from a 2018 S4 and the pin 25 linbus displays a constant set of wake-up codes, is my guess.

Going through one of the seat controllers it seems that Audi uses a sti L99PM72PXP chip which wakes up when a linbus wake up signal is given. I’m guessing this is to save power when the vehicle is off.

I’m guessing these are the wake up commands for the chips between channels 10 and 1f

I assume that 44fefefdb320 is the wake up command for id 10 and the eef8ffffffff command is the end command.

Once I figure out the commands I’m hoping to build an emulator that allows the seats to function using an ardinuo and a mcp2004 chip.

t0318100044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0290
t0318110044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0300
t0318120044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0330
t0318130044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0010
t0318140044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0290
t0318150044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0300
t0318160044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0330
t0318170044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0010
t0318180044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0290
t0318190044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0300
t03181a0044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0330
t03181b0044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0010
t03181c0044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0290
t03181d0044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0300
t03181e0044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0330
t03181f0044fefefdb320
t0320
t00b0
t0230
t00c6eef8ffffffff
t0010
t0318100044fefefdb320

2

Thank You for telling us.

3

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4

Awesome thanks so much. I’m trying to figure this out. Seems like there’s some posts on linbus stuff but not really any movement on it.