08-27-2025, 07:30 PM
Quote:I am thinking of putting a single chip LIN controller to emulate the on /off and connect this to the LIN wire, maybe someone has tried that? The LIN protocol seems easy and cheap.
It's not that simple (on / off) and hacking the LIN is much harder than hacking the CAN BUS.
LIN bus works in master / slave and each node has its own unique identifier and each node responds to specific messages (message IDs) from those unique nodes and a LIN bus network cannot have more than 1 master node.
First, there is a handshake initiated via Master (in your case CEM) which the slave (wireless charger) responses.
Then CEM (master) send operational command and the wireless charger (slave) responses with status.
VOLVO makes CAN, LIN and FLEXRAY buses much harder to hack by sending same operational commands every couple of milliseconds and not by just charging couple of bytes in the messages only once.
This means,
CEM sends handshake message if the wireless charging option is enabled.
Then by default CEM sends turn off charging message to slave "your wireless charger" every couple of milliseconds.
User presses on turn on wireless from the screen.
IHU sends turn on wireless request to CEM via Flexray every couple of milliseconds and waits for response.
CEM sends turn on charging message to slave "your wireless charger" every couple of milliseconds. and waits for response.
If the wireless charger does not receive "turn on" command every x millisecond, it turns itself off.
In order to hack the LIN bus you will need to build a man in the middle board that has one slave "acts as wireless charger" and a master "acts as CEM".
In between your code should catch, manipulate and respond on both sides.
So, instead of getting into this trouble, just order a wireless charger from amazon or aliexpress for $40 that also has two additional USB ports powered from the cigarette lighter.