Discover CAN Bus commands on a 2002 S60, part of Volvo P2 platform.
Main goal is to controll different features of the car from a mobile app, e.g. central locking or power windows. First you need point where you can connect to the CAN bus. This car features 2 separate network opearting on different speed, low speed on 125 Kbps and high speed on 250 Kbps. After facelift the HS bus speed is bumped up to 500 Kbps, but always check your car's specification. Speed critical ECU's are connected to the HS network like ECM, everything else is on the LS network. CEM has access to both network and wiring out to the OBD port, but on pre-facelift cars these signals are hidden with a diagnostic relay. To open this relay, I used the OEM diagnostic software VIDA, a chinese copy of OEM hardware VXDIAG and an OBD Y splitter cable to connect an other device simultaneously. After starting a diagnostic session, the relay will stay open. Find more about Volvo specific abrevations here.
- Arduino Uno (chinese)
- MCP2515 (chinese)
Demonstrate the ability to send commands to the car from an arduino. Write a string from serial input to DIM's 2x16 character LCD screen, using the CAN ID of PHM. Works without an actual PHM.
- Migrate from arduino to ESP32, needs a CAN transciever only (SJA1000)
- Find more CAN command
- Build a mobile app with Bluetooth connection to ESP32
- Send message on K-Line to keep diagnostic relay open, or use an other point for hardware connection like REM.
After connecting to the HS bus, several ECU registered a communication fault code and the check engine light stayed on at DIM till I did a fault code erase with VIDA. Haven't experienced this on LS bus. Configuring an incorrect CAN speed will definitely upset your setup and could possible even DAMAGE YOUR CAR. Always check your vehicle's specs before moving on.