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Diagnostic Test

  1. CHECK FOR PRESENCE OF SHORT CIRCUIT TO BATTERY ON THE CAN H (HS-CAN) LINE 
    1. Measure the voltage between pin F of the diagnostic connector (CAN H line) and body.

      Is a voltage of 12 V measured?

      Yes 

      • Short circuit to battery has occurred on the CAN H line.
      • Go To  3.

      No 

      • Go To  2.
  2. CHECK FOR PRESENCE OF SHORT CIRCUIT TO GROUND ON THE CAN H (HS-CAN) LINE 
    1. Measure the voltage between pin E of the diagnostic connector (CAN L line) and ground.

      Is voltage higher than 0 V?

      Yes 

      • Short circuit to ground has occurred on the CAN L line.
      • Go To  7

      No 

      • Go To  5.
  3. CHECK FOR PRESENCE OF SHORT CIRCUIT TO BATTERY ON THE HS-CAN LINE 
    1. Pin F of the diagnostic connector (CAN H line) and body.
    2. Pin E of the diagnostic connector (CAN L line) and body.

      Is a voltage of 12 V measured between any one of these pins?

      Yes 

      • Short circuit to battery has occurred on the HS-CAN line.
      • Go To  4.

      No 

      • Go To  5.
  4. CHECK FOR PRESENCE OF SHORT CIRCUIT TO BATTERY OF THE ANTILOCK BRAKE SYSTEM (ABS) MODULE 
    1. Go to key-off condition.
    2. Disconnect the negative battery lead.
    3. Disconnect the Antilock Brake System (ABS) Module connector.
    4. Connect the negative battery lead.
    5. Go to key-on condition (engine off).
    6. Measure voltage on pins F and E of the diagnostic connector.

      Is the measured voltage 1.5 - 3.5 V?

      Yes 

      • Replace the Antilock Brake System (ABS) Module because subject to short circuit to battery.
      • If the DTC occurs again, move on to Step  9.

      No 

      • Repair or replace the wiring between Antilock Brake System (ABS) Module and the rest of the system because the wiring is subject to short circuit to battery.
  5. CHECK FOR PRESENCE OF OPEN CIRCUIT ON THE HS-CAN LINE 
    1. Pin F of the diagnostic connector (CAN H line) and body.
    2. Pin E of the diagnostic connector (CAN L line) and body.

      Is the voltage between the terminals the same?

      Yes 

      • Short circuit has occurred between the terminals of the HS-CAN line.
      • Go To  6.

      No 

      • Check the electrical connections again.
      • Replace the Antilock Brake System (ABS) Module if the DTC occurs again.
  6. CHECK FOR PRESENCE OF FAULT ON THE HS-CAN LINE CIRCUIT 
    1. Pin F of the diagnostic connector (CAN H line) and body.
    2. Pin E of the diagnostic connector (CAN L line) and body.

      Does the voltage between the pins correspond to 0V?

      Yes 

      • Short circuit to ground has occurred on the CAN H (HS-CAN) line.
      • Go To  7.

      No 

      • A short circuit between the CAN H and the CAN L (HS-CAN) has occurred.
      • Go To  8.
  7. CHECK FOR PRESENCE OF SHORT CIRCUIT TO GROUND ON THE ANTILOCK BRAKE SYSTEM (ABS) MODULE CAN LINE 
    1. Disconnect the Antilock Brake System (ABS) Module connector.
    2. Pin C of Antilock Brake System (ABS) Module (wiring side) and body.
    3. Pin D of Antilock Brake System (ABS) Module (wiring side) and body.

      Is short-circuit present?

      Yes 

      • Repair or replace the wiring between Antilock Brake System (ABS) Module and the rest of the system because the wiring is subject to short circuit to ground.

      No 

      • Replace the Antilock Brake System (ABS) Module because subject to short circuit to ground.
      • If the DTC occurs again, move on to Step  9.
  8. CHECK FOR PRESENCE OF SHORT CIRCUIT BETWEEN THE ANTILOCK BRAKE SYSTEM (ABS) MODULE TERMINALS 
    1. Disconnect the Antilock Brake System (ABS) Module connector.
    2. Disconnect the negative battery lead.
    3. Disconnect the Antilock Brake System (ABS) Module connector.
    4. Check continuity between pin C and pin D (wiring side) of the Antilock Brake System (ABS) Module.

      Is short-circuit present?

      Yes 

      • Repair or replace the wiring between Antilock Brake System (ABS) Module and the rest of the system because the wiring is subject to short circuit to between the terminals.

      No 

      • Replace the Antilock Brake System (ABS) Module because subject to short circuit to between the terminals.
      • If the DTC occurs again, move on to Step  9.
  9. CHECK THAT THE BODY COMPUTER MODULE IS WORKING PROPERLY 
    1. Carry out the Body Computer Module DTC deletion procedure.
    2. Check whether the DTC is still present.

      Is the DTC still present?

      Yes 

      • Repeat the checks from Step  1.
      • Replace the Body Computer Module if the DTC occurs again.

      No 

      • End of diagnosis.
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