B1BBB
B1BBB-PASSENGER SEAT WEIGHT SENSOR INPUTS SHORTED TOGETHER
For a complete wiring diagram, refer to the Wiring Information Electrical Diagrams.
- When Monitored:
While the CAN bus ignition status is in IGN_RUN.
- Set Condition:
If the Occupant Classification Module (OCM) detects any two sensors voltages below 20 mV for ten minutes while any other sensor is greater than 40 mV. (Note: 1 A/D count is equal to 5 mV.)
NOTE: A shorted supply circuit will cause a 'NO RESPONSE FROM OCM" condition.
Possible Causes:
1. VERIFY THAT B1BBB-PASSENGER SEAT WEIGHT SENSOR INPUTS SHORTED TOGETHER DTC IS ACTIVE
1. With the scan tool, read the OCM DTCs.
Does the scan tool display active B1BBB-PASSENGER SEAT WEIGHT SENSOR INPUTS SHORTED TOGETHER DTC?
Yes
- Go To 2
No
- Go To 5
2. 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 the condition inspecting or testing for is present in the Seat Harness.
- Replace the Passenger Seat Harness.
- Perform the RE-ZERO OCM SEAT WEIGHT SENSORS diagnostic procedure. Re-Zero OCM Seat Weight Sensors.
No
- Go To 3
3. CHECK VOLTAGE OF (R701) SEAT WEIGHT SENSOR 5 VOLT SUPPLY CIRCUIT
1. Disconnect all four of the Seat Weight Sensor 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.
2. Measure the voltage of the (R701) Seat Weight Sensor 5 Volt supply circuit on all four seat weight sensors.
NOTE: Two Seat Weight Sensors should show a considerable difference in 5 Volt supply circuit voltage.
Is the voltage above 4.8 volts?
Yes
- Go To 5
No
- Go To 4
4. CHECK THE APPROPRIATE (R701) SEAT WEIGHT SENSOR 5 VOLT SUPPLY CIRCUIT FOR A SHORT TO THE OTHER APPROPRIATE (R701) SEAT WEIGHT SENSOR 5 VOLT SUPPLY 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. Measure the resistance between the (R701) Seat Weight Sensor supply circuit of the two suspect seat weight sensors.
Is the resistance below 10k Ohms?
Yes
- Repair the (R701) Seat Weight Sensor 5 Volt supply circuit of the suspect sensors shorted together.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Airbag System Verification Test
No
- WARNING: If the Occupant Restraint Controller (ORC) is dropped at any time, it must be replaced. Failure to follow these instructions may result in possible serious or fatal injury.
- Replace the OCM.
- Perform the B1BA7 - OCCUPANT CLASSIFICATION SYSTEM VERIFICATION REQUIRED diagnostic procedure. B1BA7
5. TEST FOR INTERMITTENT CONDITION
1. With the scan tool, record and erase all DTCs from the OCM.
2. If any ACTIVE codes are present they must be resolved before diagnosing any stored codes.
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.
3. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
4. Look for chafed, pierced, pinched, or partially broken wires and broken, bent, pushed out, spread, corroded, or contaminated terminals.
5. The following additional checks may assist you in identifying a possible intermittent problem.
6. Reconnect any disconnected components and harness 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.
7. With the scan tool monitor active codes as you work through the following steps.
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.
8. Wiggle the wiring harness and connectors of the related airbag circuit or component.
9. If only stored codes return continue the test until the problem area has been isolated.
10. In the previous steps you have attempted to recreate the conditions responsible for setting the active DTC in question.
Are any ACTIVE DTCs present?
Yes
- Select the appropriate DTC from DTC list. Testing and Inspection
- Perform the Occupant Classification Module System Verification Test. Verification Tests
No
- No problem found at this time. Perform the Occupant Classification Module System Verification Test. Verification Tests Erase all codes before returning vehicle to customer.