Hi,
I assume you have MPC5606B device. There should be no difference in CAN_3. What do you mean by "CAN_3 doesn't work" in fact? Module cannot be configured, does not leave Freeze mode, errors are detected (if yes which one)?
You can do following to check basic setting...
- are you able to write CAN_3 registers? Check if the module is clocked, see MC_ME module.
- do you use proper pad setting in the SIUL? you can try connect CAN_3 TX/RX pin together, without transceiver and send message. You should see message there.
BR, Petr