B1B84
B1B84-PASSENGER SEAT WEIGHT SENSOR 4 - LEFT REAR INPUT CIRCUIT HIGHB1B84-Passenger Seat Weight Sensor 4 - Left Rear 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.
POSSIBLE CAUSES
- Passenger seat harness improperly routed
- Passenger seat harness wires chaffed, pierced, pinched, partially broken
- Passenger seat harness connector terminals broken, bent pushed out, spread,corroded, contaminated
- (R705) LT-RR seat weight sensor signal circuit shorted to voltage
- (R705) LT-RR seat weight sensor signal circuit shorted to (R701) seat weight sensor 5 volt circuit
- (R728) seat weight sensor ground circuit open
- Left-rear seat weight sensor
- Occupant classification module (OCM)
DIAGNOSTIC TEST
1. CHECK FOR ACTIVE INTERNAL FAULTS, IGNITION FAULTS, & BATTERY FAULTS IN THE OCCUPANT CLASSIFICATION MODULE (OCM)
NOTE:
- Ensure the battery is fully charged.
- When reconnecting Airbag system components, the ignition must be turned off and the battery must be disconnected.
Turn the ignition on, then off, and then on again.
With the scan tool, read Occupant Classification Module (OCM) DTCs.
Q: Does the scan tool display any active DTCs relating to internal faults, ignition faults, or battery faults?
YES: Diagnose and repair the DTCs.
NO: Go To 2
2. VERIFY THAT DTC B1B84-PASSENGER SEAT WEIGHT SENSOR 4 - LEFT REAR INPUT CIRCUIT HIGH IS ACTIVE
With the scan tool, read OCM DTCs.
Q: Does the scan tool display active: B1B84-PASSENGER SEAT WEIGHT SENSOR 4 - LEFT REAR INPUT CIRCUIT HIGH?
YES: Go To 3
NO: Go To 9
3. INSPECT PASSENGER SEAT HARNESS WIRES & CONNECTORS
WARNING: TO AVOID PERSONAL INJURY OR DEATH, TURN THE IGNITION OFF, DISCONNECT THE BATTERY AND WAIT TWO MINUTES BEFORE PROCEEDING.
Using the wiring diagram/schematic as a guide, inspect the Passenger Seat Harness wiring and connectors. Look for chaffed, pierced, pinched, or partially broken wires and broken, bent, pushed out, spread, corroded, or contaminated terminals.
Q: Are any of these conditions present?
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.
Replace the Passenger Seat Harness. Perform OCS VERIFICATION TEST - VER 1. OCS Verification Test
NO: Go To 4
4. VERIFY THAT PASSENGER SEAT HARNESS IS ROUTED CORRECTLY
Verify that the Passenger Seat Harness is routed correctly.
Q: Is the Passenger Seat Harness routed correctly?
YES: Go To 5
NO: Reroute the Passenger Seat Harness as necessary. Perform OCS VERIFICATION TEST - VER 1. OCS Verification Test
5. CHECK IF MORE THAN ONE PASSENGER SEAT WEIGHT SENSOR DTC IS ACTIVE
Verify that all of the Seat Weight Sensor mounting screws are torqued to specification.
WARNING: TO AVOID PERSONAL INJURY OR DEATH, TURN THE IGNITION ON, THEN RECONNECT THE BATTERY.
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; & Perform The Occupant Classification Module System Verification Test To Completion.
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.
With the scan tool, read OCM DTCs.
Q: Does the scan tool display any active PASSENGER SEAT WEIGHT SENSOR DTCs?
YES - More Than One PASSENGER SEAT WEIGHT SENSOR DTC Is Active
Perform the Diagnosis/Checkout Procedure For Seat Weight Sensors. Perform OCS VERIFICATION TEST - VER 1. OCS Verification Test
YES - Only DTC B1B84 Is Active
Go To 6
NO - But Other DTCs Present
Diagnose and repair the DTCs.
NO - Active DTCs Present
Perform OCS VERIFICATION TEST - VER 1. OCS Verification Test
6. CHECK (R705) LT-RR SEAT WEIGHT SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE
WARNING: TO AVOID PERSONAL INJURY OR DEATH, TURN THE IGNITION OFF, DISCONNECT THE BATTERY AND WAIT TWO MINUTES BEFORE PROCEEDING.
Disconnect the OCM C2 connector.
Measure the voltage of the (R705) LT-RR Seat Weight Sensor Signal circuit.
Q: Is the voltage above 0.2 volts?
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.
Replace the Passenger Seat Harness. Perform OCS VERIFICATION TEST - VER 1. OCS Verification Test
NO: Go To 7
7. CHECK (R705) LT-RR SEAT WEIGHT SENSOR SIGNAL CIRCUIT FOR A SHORT TO (R701) SEAT WEIGHT SENSOR 5 VOLT CIRCUIT
Disconnect the Left-Rear Seat Weight Sensor connector.
Measure the resistance between the (R705) LT-RR Seat Weight Sensor Signal circuit and the (R701) Seat Weight Sensor 5 volt circuit.
Q: Is the resistance below 10K ohms?
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.
Replace the Passenger Seat Harness. Perform OCS VERIFICATION TEST - VER 1. OCS Verification Test
NO: Go To 8
8. CHECK (R728) SEAT WEIGHT SENSOR GROUND CIRCUIT FOR AN OPEN
Measure the resistance of the (R728) Seat Weight Sensor Ground circuit between the OCM C2 connector and the Left-Rear Seat Weight Sensor connector.
Q: Is the resistance below 5.0 ohms?
YES: Replace the OCM. Perform OCS VERIFICATION TEST - VER 1. OCS Verification Test
NO:
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.
Replace the Passenger Seat Harness. Perform OCS VERIFICATION TEST - VER 1. OCS Verification Test
9. TEST FOR INTERMITTENT CONDITION
With the scan tool, record and erase all DTCs from all Airbag modules.
If any ACTIVE codes are present they must be resolved before diagnosing any stored codes.
WARNING: TO AVOID PERSONAL INJURY OR DEATH, TURN THE IGNITION OFF, DISCONNECT THE BATTERY AND WAIT TWO MINUTES BEFORE PROCEEDING.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Look for chaffed, pierced, pinched, or partially broken wires and broken, bent, pushed out, spread, corroded, or contaminated terminals.
The following additional checks may assist you in identifying a possible intermittent problem.
Reconnect any disconnected components and harness connector.
WARNING: TO AVOID PERSONAL INJURY OR DEATH, TURN THE IGNITION ON, THEN RECONNECT THE BATTERY.
With the scan tool, monitor active codes as you work through the following steps.
WARNING: TO AVOID PERSONAL INJURY OR DEATH, MAINTAIN A SAFE DISTANCE FROM ALL AIRBAGS WHILE PERFORMING THE FOLLOWING STEPS.
Wiggle the wiring harness and connectors of the related airbag circuit or component.
If codes are related to the Driver Airbag circuits, rotate the steering wheel from stop to stop.
If only stored codes return, continue the test until the problem area has been isolated.
In the previous steps you have attempted to recreate the conditions responsible for setting the active DTC in question.
Q: Does the scan tool display any ACTIVE DTCs?
YES: Select appropriate symptom.
NO: No problem found at this time. Erase all codes before returning vehicle to customer.