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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.
      • Move on to  3.

      No 

      • Move on 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.
      • Move on to  7.

      No 

      • Move on 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.
      • Move on to  4.

      No 

      • Move on to  5.
  4. CHECK FOR PRESENCE OF SHORT CIRCUIT TO BATTERY OF THE ELECTRIC POWER STEERING MODULE 
    1. Go to key-off condition.
    2. Disconnect the negative battery lead.
    3. Disconnect the Electric Power Steering 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 Electric Power Steering Module because subject to short circuit to battery.
      • If the DTC occurs again, move on to  9.

      No 

      • Repair or replace the wiring between Electric Power Steering 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.
      • Move on to  6.

      No 

      • Check the electric connections again.
      • Replace the Electric Power Steering 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.
      • Move on to  7.

      No 

      • A short circuit between the CAN H and the CAN L (HS-CAN) has occurred.
      • Move on to  8.
  7. CHECK FOR PRESENCE OF SHORT CIRCUIT TO GROUND ON THE ELECTRIC POWER STEERING MODULE CAN LINE 
    1. Disconnect the Electric Power Steering Module connector.
    2. Pin B (connector B) of Electric Power Steering Module (wiring side) and body.
    3. pin C (connector B) of Electric Power Steering Module (wiring side) and body.

      Is short-circuit present?

      Yes 

      • Repair or replace the wiring between Electric Power Steering Module and the rest of the system because the wiring is subject to short circuit to ground.

      No 

      • Replace the Electric Power Steering Module because subject to short circuit to ground.
      • If the DTC occurs again, move on to  9.
  8. CHECK FOR PRESENCE OF SHORT CIRCUIT BETWEEN THE ELECTRIC POWER STEERING MODULE TERMINALS 
    1. Disconnect the Electric Power Steering Module connector.
    2. Check continuity between PIN B and pin C (connector B - wiring side) of the Electric Power Steering Module.

      Is short-circuit present?

      Yes 

      • Repair or replace the wiring between Electric Power Steering Module and the rest of the system because the wiring is subject to short circuit to between the terminals.

      No 

      • Replace the Electric Power Steering Module because subject to short circuit to between the terminals.
      • If the DTC occurs again, move on to  9.
  9. CHECK THAT THE SELF-ADAPTIVE HEADLIGHT MODULE IS WORKING PROPERLY 
    1. Carry out the Self-Adaptive Headlight Module DTC deletion procedure.
    2. Check whether the DTC is still present.

      Is the DTC still present?

      Yes 

      • Repeat the checks from  1.
      • Replace the Self-Adaptive Headlight Module if the DTC occurs again.

      No 

      • End of diagnosis.
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