It looks like the ECM communicates with the BSI on the single wire labeled as K-Line by Citroen but also communicates on the Hi CAN through the ABS control module. See attached information.



K-Line from BSI to ECM

From BSI module 52-pin Blue connector wire number 110 pin 26 is the single CAN wire

Going to ECM 48-pin Brown connector pin J2



CAN BUS from ECM to ABS

ECM 48-pin Brown connector pin A4 wire number 17 going to ABS module pin 26

ECM 48-pin Brown connector pin B4 wire number 16 going to ABS module pin15



CAN BUS from BSI to ABS

From BSI module 52-pin Blue connector wire number 8 pin 48 going to ABS module pin 14

From BSI module 36-pin Blue connector wire number 9 pin 49 going to ABS module pin 25



CAN BUS from BSI to Instrument panel

From BSI module 36-pin Blue connector wire number 90 pin 5 going to 18-pin Black connector pin 5

From BSI module 36-pin Blue connector wire number 75 pin 6 going to 18-pin Black connector pin 6