LIN Bus Overview
What is the LIN Bus?The LIN Bus is one of many communication systems within the vehicle, others being MOST, CANBUS, FLEXRAY and Ethernet.
As I understand it the Polestar 2 has over a dozen LIN Bus networks for different areas of the car.
The information shared here is gained from passively snooping each LIN Bus and listening to the standard 'chatter' of the Polestar communication network. .
LIN Bus is used in vehicles as a cheap single wire communication system between a master and one or several slaves. The communication system itself is cheaper and slower than other systems such as CANBUS. The system is based on the earlier K-line system. None of the LIN Bus systems in the vehicle are exposed for public use. To access the bus systems panels and modules need to be removed
What information do I expect to find on a LIN Bus?
A whole myriad of information should be available, this information is typically specific to the small network and a dedicated function. i.e. Window control, light control, steering wheel buttons etc.
Equipment used for LIN Bus logging
In its simplest form you can use an Arduino with a LIN Bus shield or an external Lin Bus to UART converter (something based around the Philips TJA1020).
The LIN Bus runs much slower than CANBUS or Ethernet systems, typically 19.2KHz.
Using the Data
Once you have parsed the data it can be used to control an Arduino, Raspberry PI(), or recorded to an SD card, or transmitted over WiFi or Bluetooth.
Polestar LIN Bus's
Please note that I am still in the process of validating the information below and completing the table.
| LIN BUS Master | Slaves on this bus | Speed | Wire Colour |
|---|---|---|---|
| CENTRAL ELECTRONIC MODULE CEM | INTERIOR MOTION SENSOR IMS | tbc | VT/WH |
| CENTRAL ELECTRONIC MODULE CEM | REAR LAMP UNIT BODY RIGHT 10/416 TRUNK LID TAIL LIGHT LOWER | tbc | WH |
| CENTRAL ELECTRONIC MODULE CEM | OVERHEAD CONSOLE REAR LEFT 4/200 OVERHEAD CONSOLE REAR RIGHT OVERHEAD CONSOLE OHC OVERHEAD CONSOLE REAR OHCR | tbc | WH |
| CENTRAL ELECTRONIC MODULE CEM | TELEMATICS AND CONNECTIVITY ANTENNA MODULE TCAM | tbc | GN |
| CENTRAL ELECTRONIC MODULE CEM | BATTERY BACKED-UP SOUNDER BBS | tbc | VT/WH |
| CENTRAL ELECTRONIC MODULE CEM | WIPER MOTOR MODULE WMM | tbc | WH |
| CENTRAL ELECTRONIC MODULE CEM | INTERIOR REAR VIEW MIRROR MODULE IRMM RAIN AND LIGHT SENSOR MODULE RLSM | tbc | WH |
| CENTRAL ELECTRONIC MODULE CEM | AIRBORNE PARTICULATE MATTER SENSOR APMS | tbc | WH |
| CENTRAL ELECTRONIC MODULE CEM | STEERING WHEEL MODULE SWM SUN SENSOR SUS | tbc | WH/GN |
| DRIVER INFORMATION MODULE DIM | STEERING WHEEL MODULE SWM | tbc | WH/GN |
| INFOTAINMENT HEAD UNIT IHU | REAR CONSOLE SWITCH MODULE RCSM CENTER CONSOLE SWITCH MODULE CCSM | tbc | WH/GN |
| ENGINE CONTROL MODULE ECM | ACTIVE GRILLSHUTTER MODULE AGM | tbc | WH/GN |
| VEHICLE COMPUTATIONAL UNIT 1 VCU1 | HIGH VOLTAGE COOLANT HEATER Alfa HVHA AIR CONDITION COMPRESSOR MODULE A ACCA ELECTRICAL EXPANSION VALVE EXV CLIMATE COOLANT VALVE MODULE CCVM | tbc | GN |
| VEHICLE COMPUTATIONAL UNIT 1 VCU1 | ELECTRONIC GEAR SELECTOR MODULE EGSM COOLANT PUMP ELECTRIC DRIVETRAIN CPED BATTERY COOLANT WATER PUMP 1 COMPARTMENT COOLANT PUMP MODULE CCPM | 19200 | WH/GN |
| CLIMATE CONTROL MODULE CCM | SEAT HEATING MODULE REAR SHMR SEAT MODULE LEFT SML SEAT MODULE LEFT SML | tbc | WH |
| FRONT RIGHT DOOR MODULE | DRIVER DOOR SWITCHES DDS REAR RIGHT DOOR MODULE | tbc | WH/GN |
| STEERING WHEEL MODULE SWM | STEERING WHEEL SWITCH LEFT | 19200 | WH |