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Diagnostic Test

  1. CHECK CONNECTION STATUS OF THE OCCUPANT CLASSIFICATION SYSTEM (OCS) CONTROL UNIT 
    1. Go to Key-OFF status.
    2. at least 1 minute.
    3. Disconnect the connector of Occupant Classification System (OCS) control unit.
    4. Check connector status of the front impact sensor, passenger side (Early Crash) and ensure that the terminals are not damaged, deformed, corroded or disconnected.

      Are the connectors of Occupant Classification System (OCS) control unit or of the seat intact?

      Yes 

      • Go to Step  2.

      No 

      • Replace or repair the connector, then move on to Step  7.
  2. CHECK FOR THE PRESENCE OF SHORT CIRCUIT TO GROUND OF THE OCCUPANT CLASSIFICATION SYSTEM (OCS) CONTROL UNIT 
    1. Disconnect the connectors of Occupant Classification System (OCS) control unit and of the fuse holder case.
    2. PIN S (connector C) of Airbag Module
    3. PIN Q (connector C) of Airbag Module

      Is short-circuit present?

      Yes 

      • Repair or replace the wiring because it is subject to a short circuit to ground, then proceed to Step  7.

      No 

      • Go to Step  3.
  3. CHECK FOR THE PRESENCE OF OPEN CIRCUIT OF THE OCCUPANT CLASSIFICATION SYSTEM (OCS) CONTROL UNIT 
    1. Disconnect the connectors of Occupant Classification System (OCS) control unit and of the fuse holder case.
    2. PIN A (connector D) of the Occupant Classification System (OCS) control unit and PIN S (connector C) of the Airbag Module
    3. PIN B (connector D) of the Occupant Classification System (OCS) control unit and PIN Q (connector C) of the Airbag Module

      Is short-circuit present?

      Yes 

      • Go to Step  4.

      No 

      • Repair or replace the wiring because it is subject to an open circuit, then proceed to Step  7.
  4. CHECK FOR THE PRESENCE OF SHORT CIRCUIT TO BATTERY OF THE OCCUPANT CLASSIFICATION SYSTEM (OCS) CONTROL UNIT 
    1. Disconnect the connectors of Occupant Classification System (OCS) control unit and of the fuse holder case.
    2. Connect the negative battery lead.
    3. Go to key-on condition (engine off or on).
    4. PIN S (connector C) of Airbag Module
    5. PIN Q (connector C) of Airbag Module

      Is voltage higher than 0 V?

      Yes 

      • Go to Step  5.

      No 

      • Repair or replace the wiring because it is subject to a short circuit to battery, then go to Step  7.
  5. CHECK CORRECT OPERATION OF OCCUPANT CLASSIFICATION SYSTEM (OCS) CONTROL UNIT 
    1. Check voltage of Occupant Classification System (OCS) control unit terminals.

      Is the voltage at every terminal normal?

      Yes 

      • Go to Step  6.

      No 

      • Repair or replace the wiring or connector, then move on to Step  6.
  6. CHECK FOR THE ERROR PERSISTENCE OF THE OCCUPANT CLASSIFICATION SYSTEM (OCS) CONTROL UNIT 
    1. Reconnect all disconnected connectors.
    2. Connect the negative battery lead.
    3. Go to key-on condition (engine off or on).
    4. Perform the Airbag Module error deletion procedure.
    5. Check if the error is still present.

      Is the error still present?

      Yes 

      • Replace the Occupant classification system (OCS) control unit, then go to Step  7.

      No 

      • End of diagnosis.
  7. CHECK CORRECT FUNCTIONING OF THE AIR-BAG MODULE 
    1. Perform the Airbag Module error deletion procedure.
    2. Check if the error is still present.

      Is the error still present?

      Yes 

      No 

      • End of diagnosis.
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