B1B7A
B1B7A-PASSENGER SEAT WEIGHT SENSOR 3 - LEFT FRONT INPUT CIRCUIT HIGH
- When Monitored:
While the CAN bus ignition status is in IGN_RUN, the module checks the sensor input ranges.
- Set Condition:
If the module detects that the sensor input is greater than 96 ± 0.6% of the (R701) Seat Weight Sensor 5 Volt circuit voltage. Note that this DTC will remain active after the condition that set this fault is no longer present. Performing the Occupant Classification Module System Verification Test will change the status from active to stored if the condition that set the fault is no longer present.
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
- Diagnose and repair the DTCs. Testing and Inspection.
No
- Go To 2
2. VERIFY THAT DTC B1B7A-PASSENGER SEAT WEIGHT SENSOR 3 - LEFT FRONT INPUT CIRCUIT HIGH IS ACTIVE
NOTE: Failure to follow test instructions or aborting the test will cause 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 Occupant Classification Module (OCM) System Verification Test.
1. 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 is complete, wait two minutes, and then proceed as follows. Occupant Classification Module (OCM) System Verification Test.
2. With the scan tool, read OCM DTCs.
Does the scan tool display active: B1B7A-PASSENGER SEAT WEIGHT SENSOR 3 - LEFT FRONT INPUT CIRCUIT HIGH?
Yes
- Go To 3
No
- Go To 9
3. VERIFY THAT DTC B1B7A-PASSENGER SEAT WEIGHT SENSOR 3 - LEFT FRONT INPUT CIRCUIT HIGH IS ACTIVE
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 all of the Seat Weight Sensor mounting screws are torqued to specification. [1][2]Mechanical Specifications.
WARNING: Turn the ignition on, then reconnect the 12-volt battery. Wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
NOTE: Failure to follow test instructions or aborting the test will cause 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. Occupant Classification Module (OCM) System Verification Test
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 is complete, wait two minutes, and then proceed as follows. Occupant Classification Module (OCM) System Verification Test.
3. With the scan tool, read OCM DTCs.
Does the scan tool display active: B1B7A-PASSENGER SEAT WEIGHT SENSOR 3 - LEFT FRONT INPUT CIRCUIT HIGH?
Yes
- Go To 4
No
- Go To 9
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
- NOTE: Do not attempt to repair the Seat Harness. Replace the Seat Harness if any of these conditions exist.
- Replace the Passenger Seat Harness.
- Perform OCCUPANT CLASSIFICATION MODULE SYSTEM VERIFICATION TEST. Occupant Classification Module (OCM) System Verification Test.
No
- Go To 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 6
No
- Re-route the Passenger Seat Harness as necessary.
- Perform OCCUPANT CLASSIFICATION MODULE SYSTEM VERIFICATION TEST. Occupant Classification Module (OCM) System Verification Test.
6. CHECK (R717) LT-FT SEAT WEIGHT SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE
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.
WARNING: Turn the ignition on, then reconnect the 12-volt battery. Wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
2. Measure the voltage of the (R717) LT-FT Seat Weight Sensor Signal circuit to ground.
Is the voltage above 0.2 of a volt?
Yes
- Replace the Passenger Seat Harness.
- Perform OCCUPANT CLASSIFICATION MODULE SYSTEM VERIFICATION TEST. Occupant Classification Module (OCM) System Verification Test.
No
- Go To 7
7. CHECK (R717) LT-FT SEAT WEIGHT SENSOR SIGNAL CIRCUIT FOR A SHORT TO (R701) SEAT WEIGHT SENSOR 5 VOLT CIRCUIT
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-Front Seat Weight Sensor connector.
2. Measure the resistance between the (R717) LT-FT Seat Weight Sensor Signal circuit and the (R701) Seat Weight Sensor 5 Volt circuit.
Is the resistance below 5.0 Ohms?
Yes
- NOTE: Do not attempt to repair the Seat Harness. Replace the Seat Harness if any of these conditions exist.
- Replace the Passenger Seat Harness.
- Perform OCCUPANT CLASSIFICATION MODULE SYSTEM VERIFICATION TEST. Occupant Classification Module (OCM) System Verification Test.
No
- Go To 8
8. CHECK (R728) SEAT WEIGHT SENSOR GROUND CIRCUIT FOR AN OPEN
1. Measure the resistance of the (R728) Seat Weight Sensor Ground circuit between the OCM C2 connector and the Left-Front Seat Weight Sensor connector.
Is the resistance below 5.0 Ohms?
Yes
- Replace the OCM.
- Perform OCCUPANT CLASSIFICATION MODULE SYSTEM VERIFICATION TEST. Occupant Classification Module (OCM) System Verification Test.
No
- NOTE: Do not attempt to repair the Seat Harness. Replace the Seat Harness if any of these conditions exist.
- Replace the Passenger Seat Harness.
- Perform OCCUPANT CLASSIFICATION MODULE SYSTEM VERIFICATION TEST. Occupant Classification Module (OCM) System Verification Test.
9. CHECKING STORED OR INTERMITTENT CODES
NOTE: Diagnose and repair all active codes before diagnosing stored codes. Testing and Inspection for a complete list of airbag system diagnostic procedures.
1. With the scan tool, record and erase all Airbag System Module DTCs.
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.
2. Using the wiring diagram/schematic as a guide, inspect the related wiring and connectors for chafed, pierced, pinched, and partially broken wires, and for broken, bent, pushed out, corroded, and contaminated terminals. Repair as necessary.
3. Reconnect all disconnected components and harness connectors.
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.
4. With the scan tool, monitor for active codes while performing the following:
WARNING: Maintain a safe distance from all airbags while performing the following steps. Failure to follow these instructions may result in possible serious or fatal injury.
- Wiggle the wiring harness and connectors of the related airbag circuit.
- Continue the test until either a code becomes active or the problem area is isolated.
5. In the previous steps you have attempted to recreate the conditions responsible for setting the DTC in question/causing the intermittent condition.
Are any ACTIVE DTCs present?
Yes
- Testing and Inspection Perform the appropriate diagnostic procedure.
No
- No problem found at this time. Perform the Occupant Classification Module System Verification Test. Erase all codes before returning vehicle to customer. Occupant Classification Module (OCM) System Verification Test.