Diagnostic Test
- 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.
- Turn the ignition on, then off, and then on again.
- With the scan tool, read OCM DTCs.
Does the scan tool display any active DTCs relating to internal faults, ignition faults, or battery faults?
Yes
- Diagnose and repair the DTC. See DTC-Based Diagnostics/MODULE, Occupant Classification (OCM) - Diagnosis and Testing for a complete list of DTCs.
No
- Go to step 2
- VERIFY ACTIVE DTC
- With the scan tool, read OCM DTCs.
Does the scan tool display active B1B78-PASSENGER SEAT WEIGHT SENSOR 3 - LEFT FRONT PERFORMANCE DTC?
Yes
- Go to step 3
No
- Perform the OCS INTERMITTENT TEST. See DTC-Based Diagnostics/MODULE, Occupant Classification (OCM) - Standard Procedure .
- With the scan tool, read OCM DTCs.
- 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.
- 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.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.
Are any of these conditions present?
Yes
- 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 4
- 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.
- REZERO SEAT WEIGHT SENSORS NOTE: The Occupant Classification System Seat Weights 9077 are required to perform this test.
- Verify that the passenger seat is empty.
- Remove any special tools or jumper wires and reconnect all previously disconnected components - except the battery.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.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.
- 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.
- With the scan tool, read the OCM DTCs.
Does the scan tool display active B1B78-PASSENGER SEAT WEIGHT SENSOR 3 - LEFT FRONT PERFORMANCE DTC?
Yes
- Go to step 5
No
- Perform the OCS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Occupant Classification (OCM) - Standard Procedure .
- VERIFY PASSENGER SEAT RISER, TRACKS AND STRUCTURE 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.
- Verify that the passenger seat is empty.CAUTION: To avoid seat weight sensor damage, the Strain Gage Alignment Tool 9698A must be used to when loosening or tightening the sensor retainers.
- Make sure all Seat Weight Sensor mounting screws are tightened to specification. Refer to Restraints - Specifications
.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.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.
- 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.
- With the scan tool, read the OCM DTCs.
Does the scan tool display active B1B78-PASSENGER SEAT WEIGHT SENSOR 3 - LEFT FRONT PERFORMANCE DTC?
Yes
- Perform the DIAGNOSIS AND CHECKOUT PROCEDURE FOR SEAT WEIGHT SENSORS diagnostic procedure. See DTC-Based Diagnostics/MODULE, Occupant Classification (OCM) - Standard Procedure .
No - Other DTCs Present
- Diagnose and repair the active DTC. See DTC-Based Diagnostics/MODULE, Occupant Classification (OCM) - Diagnosis and Testing for a complete list of DTCs.
No Active DTCs Present
- Perform the OCS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Occupant Classification (OCM) - Standard Procedure .
- Verify that the passenger seat is empty.