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Diagnostic Test

  1. CHECK FOR ACTIVE INTERNAL FAULTS, IGNITION FAULTS AND BATTERY FAULTS IN THE OCCUPANT CLASSIFICATION MODULE (OCM) 
    NOTE: Make sure that the battery is fully charged.
    1. Turn the ignition on, then off and then on again.
    2. With the scan tool, read OCM DTC.

      Does the scan tool display any active DTC relating to internal faults, ignition faults or battery faults?

      Yes 

      No 

      • Go to step  2
  2. VERIFY THAT DTC B1B84-PASSENGER SEAT WEIGHT SENSOR 4 - LEFT REAR INPUT CIRCUIT HIGH IS ACTIVE 
    NOTE: Failure to follow the test instructions or aborting the test causes faults to set when performing the Occupant Classification Module System Verification Test. To prevent faults due to process errors: verify that all tests steps that led you here were performed as directed, verify that the ignition is in run. Wait 30 seconds after changing the seat weight before proceeding to allow the system to stabilize. Only press scan tool buttons when directed to do so and perform the Occupant Classification Module System Verification Test to completion.
    1. With the scan tool in OCM, select More Options, System Tests and select Occupant Classification Module System Verification Test. Run the test by following the instructions displayed on the scan tool. When the test completes, wait two minutes and then proceed as follows.
    2. With the scan tool, read the OCM DTC.

      Does the scan tool display active B1B84-PASSENGER SEAT WEIGHT SENSOR 4 - LEFT REAR INPUT CIRCUIT HIGH DTC?

      Yes 

      • Go to step  3

      No 

  3. VERIFY THAT DTC B1B84-PASSENGER SEAT WEIGHT SENSOR 4 - LEFT REAR INPUT CIRCUIT HIGH IS ACTIVE 
    1. Verify that all of the Seat Weight Sensor mounting screws are tightened to specification. Refer to Restraints - Standard Procedure .
      NOTE: Failure to follow the test instructions or aborting the test causes faults to set when performing the Occupant Classification Module System Verification Test. To prevent faults due to process errors: verify that all tests steps that led you here were performed as directed, verify that the ignition is in run. Wait 30 seconds after changing the seat weight before proceeding to allow the system to stabilize. Only press scan tool buttons when directed to do so and perform the Occupant Classification Module System Verification Test to completion.
    2. With the scan tool in OCM, select More Options, select System Tests and select Occupant Classification Module System Verification Test. Run the test by following the instructions displayed on the scan tool. When the test completes, wait two minutes and then proceed as follows.
    3. With the scan tool, read the OCM DTC.

      Does the scan tool display active B1B84-PASSENGER SEAT WEIGHT SENSOR 4 - LEFT REAR INPUT CIRCUIT HIGH DTC?

      Yes 

      • Go to step  4

      No 

  4. INSPECT PASSENGER SEAT HARNESS WIRES AND CONNECTORS 
    WARNING: Turn the ignition off, disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
    1. Using the wiring diagram/schematic as a guide, inspect the Passenger Seat Harness wiring and connectors. Look for chafed, pierced, pinched or partially broken wires and broken, bent, pushed out, spread, corroded or contaminated terminals.

      Are any of these conditions present?

      Yes 

      No 

      • Go to step  5
  5. VERIFY THAT PASSENGER SEAT HARNESS IS ROUTED CORRECTLY 
    1. Verify that the Passenger Seat Harness is routed correctly.

      Is the Passenger Seat Harness routed correctly?

      Yes 

      • Go to step  6

      No 

  6. CHECK (R705) LT-RR SEAT WEIGHT SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE 
    Fig 1: Measuring Voltage Of Left-Rear Seat Weight Sensor Signal Circuit
    GC0101811Courtesy of CHRYSLER LLC
    1. Disconnect the OCM C2 harness connector.
      WARNING: Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
    2. Measure the voltage of the (R705) LT-RR Seat Weight Sensor Signal circuit.

      Is the voltage above 0.2 of a volt?

      Yes 

        NOTE: Do not attempt to repair the Seat Harness. Replace the Seat Harness if the condition inspecting or testing for is present in the Seat Harness.
        WARNING: Turn the ignition off, disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
      • Replace the Passenger Seat Harness in accordance with the Service Information.
      • Perform the RE-ZERO OCM SEAT WEIGHT SENSORS diagnostic procedure. See DTC-Based Diagnostics/MODULE, Occupant Classification (OCM) - Standard Procedure .

      No 

      • Go to step  7
  7. CHECK (R705) LT-RR SEAT WEIGHT SENSOR SIGNAL CIRCUIT FOR A SHORT TO (R701) SEAT WEIGHT SENSOR 5-VOLT CIRCUIT 
    Fig 2: Checking Left-Rear Seat Weight Sensor Signal Circuit For A Short To Seat Weight Sensor 5-Volt Circuit
    GC0101812Courtesy of CHRYSLER LLC
    WARNING: Turn the ignition off, disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
    1. Disconnect the Left-Rear Seat Weight Sensor connector.
    2. Measure the resistance between the (R705) LT-RR Seat Weight Sensor Signal circuit and the (R701) Seat Weight Sensor 5-volt circuit.

      Is the resistance below 5.0 Ohms?

      Yes 

      No 

      • Go to step  8
  8. CHECK (R728) SEAT WEIGHT SENSOR GROUND CIRCUIT FOR AN OPEN 
    Fig 3: Checking Seat Weight Sensor Ground Circuit For An Open
    GC0101813Courtesy of CHRYSLER LLC
    1. Measure the resistance of the (R728) Seat Weight Sensor Ground circuit between the OCM C2 connector and the Left-Rear Seat Weight Sensor connector.

      Is the resistance below 5.0 Ohms?

      Yes 

        WARNING: Turn the ignition off, disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
      • Replace the OCM in accordance with the Service Information.
      • Perform the RE-ZERO OCM SEAT WEIGHT SENSORS diagnostic procedure. See DTC-Based Diagnostics/MODULE, Occupant Classification (OCM) - Standard Procedure .

      No 

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