11-12-2025, 07:30 PM
IHU does not send the commands to seat controller. IHU sends the message to CEM via FlexRay for controlling Heated, Ventilated and massage functions.
Then CEM sends the command to the seat controller(s) for massage control. It might be possible to control the massage function from the dial without seeing it on center display
controlling heated and ventilated seats that's a different story.
IHU sends command to CEM. (FlexRay)
CEM sends command to CCM (CAN BUS)
CCM sends command to seat heating / cooling module (LIN BUS).
Since you don't have none of the modules, you must replicate the LIN bus MASTER "CCM" for heated and ventilated which is not easy at all. Because each slave in the LIN bus module answers to specific messages from specific module ID. Since the same LIN bus is shared with other LIN BUS modules it would be very hard to isolate the correct messages.
Then CEM sends the command to the seat controller(s) for massage control. It might be possible to control the massage function from the dial without seeing it on center display
controlling heated and ventilated seats that's a different story.
IHU sends command to CEM. (FlexRay)
CEM sends command to CCM (CAN BUS)
CCM sends command to seat heating / cooling module (LIN BUS).
Since you don't have none of the modules, you must replicate the LIN bus MASTER "CCM" for heated and ventilated which is not easy at all. Because each slave in the LIN bus module answers to specific messages from specific module ID. Since the same LIN bus is shared with other LIN BUS modules it would be very hard to isolate the correct messages.