What's all this Chademo CAN Buss stuff anyway?

[kiev]

Turns out, like most car stuff, there are spec documents that define everything. So no surprise that the Chademo port has a CAN Buss.

The vehicle talks on Pids 0x100, 101 and 102.

The charger uses Pids 0x108 and 109.

Chademo is being phased out in many places so this is late to the show, but we might be able to figure how to send current out.

 

[kiev]

The vehicle pids


Maximum battery voltage
0x100[5, 4];
Max 0 2 5 8
16 bit, (High byte: 5, Low byte: 4)
1V/bit, 0 V to 600 V

Charged rate reference constant (for display)
0x100[6];
Fix 6 4
8 bit, 1% / bit, 100% (fixed)

Maximum charging time
0x101[1];
Max F F
8 bit, 10 s/bit, 0 s to 2540 s,
“0xFF” indicates use byte [2]

Maximum charging time (by minute)
0x101[2];
Max F F
8 bit, 1 min/bit, 0 to 255 min

Estimated charging time (by minute) 0x101[3];
Max F F
8 bit, 1 min/bit, offset 1, 0-254 min

Total capacity of battery (Optional)
0x101[6 5];
Max F F F F
16 bit, (High byte: 6, Low byte: 5)
0.1 kWh/bit, 0.0–6553.5 kWh

 

[kiev]

The charger Pids

 

[kiev]

Chademo wiring and charger side connector pinout (edits for spec typos)





This is the spec numbering scheme, note that the port numbering is different for each manufacturer for some reason, so be careful when digging.

 

[kiev]

Vehicle side schematic and connector pinout could go here
Mitsubishi


Nissan H10 connector (2018 FSM Harness Side View)


Other

 

[kiev]

Additional PIDs were added to allow for bi-directional current flow.
Vehicle side:

 

[kiev]

EVSE (Charger) side:

 

[kiev]

Late to the show, Dala the Great has already decoded all these PIDs on his github,
https://github.com/dalathegreat/leaf_can_bus_messages/blob/master/QC-CAN_ALL.dbc

 

[hjdlsnbc]

Do you know where is the best and least invasive place in the car to listen to this CAN bus? Is the only solution to not have to cut into the cables to get to the EV-ECU plug and make a extension cable?

The information have not been written here and is probably important for people who would like to listen to the CAN bus: The chademo can traffic is separate. You cant listen to the communication between the charger and the car at OBD2 port. This is implemented by Mitsubishi on separate data traffic for many reasons.
A person who have build his own chademo implementation in his car skipped to split the CAN traffic and is sending all the CAN bus data from his car to every charger he uses. Until now he had no critical issues, but that is still not recommended.

 

[MickeyS70]

Is the only solution to not have to cut into the cables to get to the EV-ECU plug and make a extension cable?

Probably yes, as the EV-ECU is easily accessible under the back seat bench, no need to cut cables, use T crimps instead.