CAN Communication Circuit Inspection

■ CAN communication line inspection 

1. IG KEY OFF.
2. Disconnect LDC connector and MCU connector.
3. Measure the resistance between CAN-HIGH terminal of LDC harness connector and CAN-HIGH terminal of MCU harness connector.
4. Measure the resistance between CAN-LOW terminal of LDC harness connector and CAN-LOW terminal of MCU harness connector.

   Specification  : Below 1Ω

   Fig 1: Measuring Resistance Between CAN-LOW & CAN-HIGH Terminals Of LDC Harness Connector And CAN-LOW & CAN-HIGH Terminals Of MCU Harness Connector

   Courtesy of HYUNDAI MOTOR AMERICA
   Fig 2: Identifying FATC, PCM, LDC, AAF, DLC, BMS & HCU Connector End Views

   Courtesy of HYUNDAI MOTOR AMERICA
5. Is the measured resistance within specification?

   YES 

   • Check Each Module connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.
   • Substitute with a known - good Each Module and check for proper operation. If the problem is corrected, replace ECM and go to "VERIFICATION OF VEHICLE REPAIR " procedure.

   NO 

   • Check for open/short in harness.
   • Repair as necessary and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.