[kennybobby]

Don't know if anyone plans or needs to reverse the Leaf CAN buss, but i've been collecting some information from the Factory Service Manual to get an overview of their system.

One missing item of interest would be the Consult manual, which is the tool used by the OEM service dept to read and troubleshoot DTCs, write ECU data, etc. Be on the lookout it would be great to see this too.



Index
1. Abbreviations used by CAN/Consult
2. CAN frame fields
3. CRC calculation (found online, not in FSM
4. CAN block diagram
5. CAN signal list

 

[kennybobby]

Re: 2012 Leaf CAN frame fields

Basic info on the fields, and a CRC calculation found online at
http://productions.8dromeda.net/c55-leaf-inverter-protocol.html

Nissan CRC:
	static void nissan_crc(uint8_t *data) {
		data[7] = 0;
		uint8_t crc = 0;
		for (int b=0; b<8; b++) {
			for (int i=7; i>=0; i--) {
				uint8_t bit = ((data[b] &(1 << i)) > 0) ? 1 : 0;
				if(crc >= 0x80) crc = (byte)(((crc << 1) + bit) ^ 0x85);
				else            crc = (byte)((crc << 1) + bit);
			}
		}
		data[7] = crc;
	}

 

[kennybobby]

Re: 2012 Leaf CAN Block Diagram

Overview block diagram. Two CAN busses that connect thru the VCM, a Car Buss and an EV buss.

It appears that both are routed to the Data Link Connector, aka OBDII connector under the knee panel below steering wheel, but it will take a more detailed look to discover the pinout.

Don't know if there is a junction block connector somewhere such that the EV CAN buss could be monitored to get samples. i get the impression that the leaf spy tool mentioned in a post below sends commands and reads the response thru the VCM to get it's data.

 

[kennybobby]

Re: 2012 Leaf CAN Signal Listing

This needs to be fleshed out to match the signals with the actual CAN PIDs, and a lot of that has been done by folks over on the myleaf forum, but it is so organized that i can follow and understand very little to none of it, haha guess i'm slow...

 

[kennybobby]

Leaf Spy Tool

There is a phone app that reads CAN data from the OBDII port using a blueteeth or wifi dongle, it is discussed on the myleaf forum and can be found by searching for leafspy, there may be 3 versions. The Lite version will read the voltage of each cell in the pack, which makes it a very useful tool.