LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Jeep >> 2010 >> Liberty Limited, 4WD, Part Time >> Repair and Diagnosis >> Restraints >> Restraints Control Systems >> Occupant Classification Module (OCM) - Electrical Diagnostics >> DTC Troubleshooting >> B1B88-Passenger Seat Weight Sensor 1 - Right Rear Input Circuit Low >> Diagnostic Test
April 5, 2026: LEMON Manuals is launched! Read the announcement.

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 Occupant Classification Module (OCM) DTCs.

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

      Yes 

      No 

      • Go to step  2
  2. VERIFY THAT DTC B1B88-PASSENGER SEAT WEIGHT SENSOR 1 - RIGHT REAR INPUT CIRCUIT LOW IS ACTIVE 
    1. With the scan tool, read OCM DTCs.

      Does the scan tool display active: B1B88-PASSENGER SEAT WEIGHT SENSOR 1 - RIGHT REAR INPUT CIRCUIT LOW?

      Yes 

      • Go to step  3

      No 

  3. VERIFY THAT DTC B1B88-PASSENGER SEAT WEIGHT SENSOR 1 - RIGHT REAR INPUT CIRCUIT LOW AND B1B89-PASSENGER SEAT WEIGHT SENSOR 1 - RIGHT REAR INPUT CIRCUIT HIGH ARE ACTIVE AT THE SAME TIME 
    1. With the scan tool, read OCM DTCs.

      Does the scan tool display active: B1B88-PASSENGER SEAT WEIGHT SENSOR 1 - RIGHT REAR INPUT CIRCUIT LOW DTC AND B1B89-PASSENGER SEAT WEIGHT SENSOR 1 - RIGHT REAR INPUT CIRCUIT HIGH DTC AT THE SAME TIME?

      Yes 

      No 

      • Go to step  4
  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 VOLTAGE OF (R701) SEAT WEIGHT SENSOR 5-VOLT CIRCUIT 
    Fig 1: Measuring Voltage Of Seat Weight Sensor 5-Volt Circuit
    GC0101815Courtesy of CHRYSLER LLC
    1. Disconnect the Right-Rear Seat Weight Sensor 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 (R701) Seat Weight Sensor 5-volt circuit.

      Is the voltage above 4.8 volts?

      Yes 

      • Go to step  7

      No 

      • Go to step  9
  7. CHECK (R706) RT-RR SEAT WEIGHT SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND 
    Fig 2: Checking Right-Rear Seat Weight Sensor Signal Circuit For A Short To Ground
    GC0101816Courtesy 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 OCM C2 connector.
    2. Measure the resistance of the (R706) RT-RR Seat Weight Sensor Signal circuit between ground and the OCM C2 connector.

      Is the resistance below 5.0 Ohms?

      Yes 

      No 

      • Go to step  8
  8. CHECK (R706) RT-RR SEAT WEIGHT SENSOR SIGNAL CIRCUIT FOR AN OPEN 
    Fig 3: Checking Right-Rear Seat Weight Sensor Signal Circuit For An Open
    GC0101817Courtesy of CHRYSLER LLC
    1. Measure the resistance of the (R706) RT-RR Seat Weight Sensor Signal circuit between the OCM C2 connector and the Right-Rear Seat Weight Sensor connector.

      Is the resistance below 5.0 Ohms?

      Yes 

      No 

  9. CHECK (R701) SEAT WEIGHT SENSOR 5-VOLT CIRCUIT FOR AN OPEN 
    Fig 4: Checking Seat Weight Sensor 5-Volt Circuit For An Open
    GC0101818Courtesy of CHRYSLER LLC
    1. Disconnect the OCM C2 connector.
    2. Measure the resistance of the (R701) Seat Weight Sensor 5-volt circuit between the OCM C2 connector and the Right-Rear Seat Weight Sensor connector.

      Is the resistance below 5.0 Ohms?

      Yes 

        WARNING: If the Occupant Classification Module (OCM) is dropped at any time, it must be replaced. Failure to take the proper precautions could result in accidental airbag deployment and 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 

  10. REPLACE THE OCCUPANT CLASSIFICATION MODULE 
    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.

    View repair

    Yes 

      WARNING: If the Occupant Classification Module (OCM) is dropped at any time, it must be replaced. Failure to take the proper precautions could result in accidental airbag deployment and 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 .