Nissan Leaf BMS

Here we collect information about Nissans BMS.

Connectors

Credit goes to Wolftronix for figuring this out.

You will also find it on the diyelectriccar forum, you will need to sign up for downloading

P4 24 pin				P3 32 pin				P6 16 Pin				P5 40 Pin
Pin	Cell	Cell	Pin	Pin	Cell	Cell	Pin	Pin	Cell	Cell	Pin	Pin	Cell	Cell	Pin
1	1		13	1	21		17	1			9	1	61	60	21
2	3	2	14	2	23	22	18	2	49	48	10	2	63	62	22
3	5	4	15	3	25	24	19	3	51	50	11	3	65		23
4	7	6	16	4	27	26	20	4	53	52	12	4	67	64	24
5	9	8	17	5	29	28	21	5	55	54	13	5	69	66	25
6	11	10	18	6	31	30	22	6	57		14	6	71	68	26
7	13	12	19	7	33	32	23	7	59	56	15	7	73	70	27
8	15	14	20	8		34	24	8		58	16	8	75	72	28
9		16	21	9	35	36	25					9	77	74	29
10			22	10	37	38	26					10	79	76	30
11	17	18	23	11	39	40	27					11		78	31
12	19	20	24	12	41	42	28					12	81	80	32
				13	43	44	29					13	83	82	33
				14	45	46	30					14	85	84	34
				15	47	48	31					15	87	86	35
				16	49		32					16	89	88	36
												17	91	90	37
												18	93	92	38
												19	95	94	39
												20	97		40

Connector part numbers

In case you need to adapt or extend the sense wires, you will need the male and female connectors and the respective pins. Here are the part numbers:

Part	Number	Notes
16-polig male	1473796-1
16-polig female	1318386-1
24-polig male	1473799-1
24-polig female	1318917-1
32-polig male	1473799-1
32-polig female	1318747-1
40-polig male	1376113-2	Solder part, crimp not available
40-polig female	1318389-1
Pin male	1376109-1
Pin female	1123343-1

CAN Messages

Upon powerup the unit spits out messages that contain various useful info. After a while these messages stop and you have to send 50B#00 00 00 C0 00 00 00 to get it going again.

All messages are big endian, i.e. hi-byte, lo-byte!

To get the individual cell voltages, first issue 79B#02 21 02 FF FF FF FF FF. You will receive the first reply looking like this: 7BB#10 C6 61 02 0E C9 0E C0.

Now send 27 times 79B#30 01 00 FF FF FF FF FF and you get 7BB#21 0E C0 0E C2 0E C0 0E. It is one index byte and 7 data bytes. So after 28 messages you will have collected 98 words (16-bit) of data. Every other message it stretches over to the next message. The first the last two words are unknown so we discard them. That leaves us with 96 Words that represent the cell voltages in mV in big endian format.