Nissan LEAF: Disconnecting TCU causes DTCs, here is how to fix this

[dalathegreat]

What

When disconnecting the original TCU to run the OVMS, you will get fault codes (P31C2 TCU EVC-273, U1000). The fault codes can be avoided with some more clever CAN message sending.

How

We need to periodically send a 100ms message onto the CAN bus when the vehicle is ON.
0x0000056e 1 0x46 (When vehicle is ON)
0x0000056e 1 0x86 (When vehicle is turning OFF, last few seconds of CAN bus activity)

This should be added to the SendCommand logic