B1B78
B1B78-PASSENGER SEAT WEIGHT SENSOR 3 - LEFT FRONT PERFORMANCE
For a complete wiring diagram, refer to the Wiring Information.
- When Monitored:
When CAN ignitions status is Run or Signal Not Available (SNA) and during the Occupant Classification Module (OCM) auto zero process or while performing the Occupant Classification Module System Verification Test.
- Set Condition:
During the Occupant Classification Module System Verification Test: if the OCM detects that the sensor input is less than 1.4 volts or greater than 3.6 volts. During auto zero: if the OCM detects that the sensor input is less than 1 volt or greater than 4 volts.
During auto zero: if the OCM detects that the sensor input is less than 1 volt or greater than 4 volts.
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 DTCs.
Does the scan tool display any active DTCs relating to internal faults, ignition faults, or battery faults?
Yes
- Diagnose and repair the DTC. Testing and Inspection for a complete list of DTCs.
No
- Go To 2
2. VERIFY ACTIVE DTC
1. 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 3
No
- Perform the OCS INTERMITTENT TEST. . OCS Intermittent Test
3. 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.
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.
- Perform the RE-ZERO OCM SEAT WEIGHT SENSORS diagnostic procedure. . Re-Zero OCM Seat Weight Sensors
No
- Go To 4
4. REZERO SEAT WEIGHT SENSORS
NOTE: The Occupant Classification System Seat Weights 9077 are required to perform this test.
1. Verify that the passenger seat is empty.
2. 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. 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. OCS Verification Test
3. 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.
4. 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 5
No
- Perform the OCS VERIFICATION TEST. OCS Verification Test.
5. 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.
1. 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.
2. Make sure all Seat Weight Sensor mounting screws are tightened to specification. [1][2]Restraints and Safety Systems.
WARNING: Turn the ignition on, then reconnect the 12-volt battery. 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. OCS Verification Test
3. 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.
4. 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. . Diagnosis and Checkout Procedure for Seat Weight Sensors.
No - Other DTCs Present
- Diagnose and repair the active DTC. Testing and Inspection for a complete list of DTCs.
No Active DTCs Present
- Perform the OCS VERIFICATION TEST. OCS Verification Test.