CAN Communication Line Inspection

■ CAN Register and Communication Line Inspection 1 

1. IG KEY OFF.
2. HCU, PCM, MCU, BMS, A.A.F, FATC Connector.
3. Measure resistance between terminal 3 and 11 of diagnostic connector.

   Specification  : About 60 Ω

   Fig 1: PCM Circuit Diagram

   Courtesy of HYUNDAI MOTOR AMERICA
   Fig 2: BMS Connector Terminals

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

   YES 

   • Check HCU, PCM, MCU, A A F, FATC, 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.

     Go to next procedure.

   NO 

   • If the measured value is out of specification, repair or replace 120 CAN register (Inside of PCM and BMS and then, go to "VERIFICATION OF VEHICLE REPAIR " procedure.

     If the measured value is lower than 10, repair or replace CAN High and CAN Low are short each other. And then, go to "VERIFICATION OF VEHICLE REPAIR " procedure.

     If the measured value is, repair or replace the open in CAN High/CAN Low circuit. And then, go to "VERIFICATION OF VEHICLE REPAIR " procedure.

     Go to next procedure.

■ CAN Register and Communication Line Inspection 2 

1. IG KEY OFF
2. Disconnect PCM connector and BMS connector.
3. Measure resistance between terminal CAN Low and CAN High of PCM.
4. Measure resistance between terminal CAN Low and CAN High of BMS.

   Specification  : About 120 Ω

   Fig 3: BMS Circuit Diagram

   Courtesy of HYUNDAI MOTOR AMERICA
   Fig 4: AAF Connector Terminals

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

   YES 

   • Go to next procedure.

   NO 

   • Substitute with a known-good "PCM, BMS" and check for proper operation. If the problem is corrected, replace "PCM, BMS" and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.

■ Check Short to Battery in CAN Communication Line. 

1. IG key "OFF".
2. Disconnect HCU, PCM, MCU, BMS, A A F, FATC connector.
3. IG KEY "ON"
4. Measure voltage between CAN High Terminal (# 3) of diagnostic connector and chassis ground.
5. Measure voltage between CAN Low Terminal (#11) of diagnostic connector and chassis ground.

   Specification  : About 0V

■ Check Short to Ground in CAN Communication Line 

1. IG key "OFF"
2. Disconnect HCU, PCM, MCU, BMS, A A F, FATC connector.
3. Measure resistance between CAN High Terminal (# 3) of diagnostic connector and chassis ground.
4. Measure resistance between CAN Low Terminal (# 11) of diagnostic connector and chassis ground.

   Specification  : ∞ Ω

   Fig 1: PCM Circuit Diagram

   Courtesy of HYUNDAI MOTOR AMERICA
   Fig 2: LDC Connector Terminals

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

   YES 

   • Check HCU, PCM, MCU, BMS, A A F, FATC 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.

   NO 

   • Check short to battery in communication line. And then, go to "VERIFICATION OF VEHICLE REPAIR " procedure.

     Check short to ground in communication line. And then, go to "VERIFICATION OF VEHICLE REPAIR " procedure.

■ CAN Communication Circuit Inspection (F.AT.C ↔ A.A.F) 

1. Ignition "OFF"
2. Disconnect A.A.F connector and F.A.T.C connector.
3. Measure the resistance between CAN-HIGH terminal of A.A.F harness connector and CAN-HIGH terminal of F.A.T.C harness connector.
4. Measure the resistance between CAN-LOW terminal of A.A.F harness connector and CAN-LOW terminal of F.A.T.C harness connector.

   Specification  : below 1 Ω

   Fig 3: Data Link Connector Circuit Diagram

   Courtesy of HYUNDAI MOTOR AMERICA
   Fig 4: AAF Connector Terminals

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

   YES 

   • Check F.A.T.C, A.A.F 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.

   NO 

   • Check for Open/Short in harness.

     Repair as necessary and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.