B2734

B2734-12-PASSENGER OCCUPANT DETECTION SENSOR CIRCUIT - SHORT TO BATTERY

Special Tools:

For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The Occupant Detection Sensor (ODS) is a resistive sensor that is located in the front passenger seat. This sensor is only used for passenger seatbelt reminder. The seat sensor assumes a passenger is present when a minimum of 53.5 pounds (20kg) of weight is placed in the seat. The resistance of the sensor decreases, signaling to the ORC module that a passenger is present. The ORC then transmits this information to the Instrument cluster over the CAN bus. The passenger is only reminded to buckle up if the passenger seat occupant minimum weight threshold determined by the ODS is surpassed and the seat belt buckle is still not latched. The ODS receives battery voltage and clean ground through dedicated sensor plus and minus circuits from the ORC. The ORC receives, processes, and continuously monitors (monitor rate of 500 ms) the analog signal from the ODS. The ODS component is not repairable, if determined inoperable, it would require to be replaced with a new component. The airbag warning lamp will not set for this fault.

- When Monitored:
The ORC receives, processes, and continuously monitors (monitor rate of 500 ms) the analog signal from the ODS.

- Set Condition:
The ORC detects High voltage on the (R283) Passenger Occupant Detector Sensor Signal circuit for 2.5 - 5 seconds. The DTC will not latch for the entire ignition cycle. The code goes from Active to Stored 2.5 - 5 seconds after the code setting criteria is gone. This code also covers the Open fault.

Always Perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Restraints System Pre-Diagnostic Procedure.

1.

NOTE: The airbag warning lamp will not set in the instrument cluster.

NOTE: The use of a approved special tool or Digital Multimeter such as a Fluke Meter that will not apply more than 20 milliamperes to a circuit are the only measurement tools to be used.

NOTE: Probing of the circuit cavities at the ORC Module C1-A, C1-B, or C2-A body harness connectors are only to be done with a approved test lead from the (10159), test lead 10159-6. Or a comparable test lead to prevent vehicle wiring harness connector damage during diagnostic procedures.
VERIFY ACTIVE DTC

NOTE: Make sure the battery is fully charged.

1. Turn the ignition on.
2. With the scan tool, read the ORC DTCs

Does the scan tool display active B2734-12-PASSENGER OCCUPANT DETECTION SENSOR CIRCUIT - SHORT TO BATTERY DTC?

Yes

- Go To 2

No

- Perform the RESTRAINT SYSTEM INTERMITTENT TEST. Restraints System Intermittent Condition Test.

2. CHECK THE (R283) PASSENGER OCCUPANT DETECTOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE

NOTE: Repair of the wiring is only to be done on the seat body harness side of the connector. If the wiring fault is in the component side of the wiring harness routed into the seat cushion a ODS sensor replacement is to be performed. Occupant Detection Sensor - Removal .

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. Keep the Passenger Occupant Detector Sensor harness connector in the seat cushion connected.
2. Keep the inline harness underseat connector connected.
3. Keep the Occupant Detection Sensor (ODS) in the passenger seat cushion connected.
4. Disconnect the ORC harness connectors.
5. Connect the appropriate test leads to the DVOM.If the vehicle is equipped with the keyless ignition, follow this ignition on warning.

WARNING: Disconnect the 12-volt battery wait two minutes before proceeding, remove the ORC fuses, connect the 12-volt battery, wait two minutes before proceeding. Cycle the ignition to the On position, then reconnect the ORC fuses. Wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
If the vehicle is equipped with the standard key ignition, follow this ignition on warning.

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.

6. Measure the voltage of the (R283) Passenger Occupant Detector Signal circuit between ground and the appropriate terminal of the ORC module body harness connector C1-B.

Is there any voltage present?

Yes

- NOTE: The ODS sensor is to be replaced whenever a short to voltage fault has been found in the ODS harness even after the harness repair has been performed.

- 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.

- Repair the (R283) Passenger Occupant Detector Signal circuit for a short to voltage.
- Replace the ODS sensor. Occupant Detection Sensor - Removal.
- Perform the RESTRAINTS SYSTEM VERIFICATION TEST. Restraints System Verification Test.

No

- Go To 3

3. CHECK THE (R283) PASSENGER OCCUPANT DETECTOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE BETWEEN THE ORC AND THE PASSENGER INLINE UNDERSEAT CONNECTOR

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.

NOTE: Check connectors - Clean/Repair as necessary.

1. Disconnect the passenger inline underseat harness connector.If the vehicle is equipped with the keyless ignition, follow this ignition on warning.

WARNING: Disconnect the 12-volt battery wait two minutes before proceeding, remove the ORC fuses, connect the 12-volt battery, wait two minutes before proceeding. Cycle the ignition to the On position, then reconnect the ORC fuses. Wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
If the vehicle is equipped with the standard key ignition, follow this ignition on warning.

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 between ground and the (R283) Passenger Occupant Detector Signal Circuit at the appropriate terminal of the ORC module body harness connector C1-B.

Is there voltage present?

Yes

- NOTE: The ODS sensor is to be replaced whenever a short to voltage fault has been found in the ODS harness even after the harness repair has been performed.

- 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.

- Repair the short to voltage in the (R283) Passenger Occupant Detector Signal Circuit located between the ORC and the passenger seat inline underseat jumper harness connector.
- Replace the ODS sensor. Occupant Detection Sensor - Removal.
- Perform the RESTRAINTS SYSTEM VERIFICATION TEST. Restraints System Verification Test.

No

- Go To 4

4. CHECK THE (R283) PASSENGER OCCUPANT DETECTOR SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE IN THE PASSENGER UNDERSEAT JUMPER HARNESS

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. Connect the passenger inline underseat harness connector.

NOTE: Confirm the connector is seated firmly and the lock tab is fully seated.

2. Access the Passenger Occupant Detector Sensor (ODS) connector located at the passenger seat cushion.
3. Disconnect the Passenger Occupant Detector Sensor (ODS) harness connector.If the vehicle is equipped with the keyless ignition, follow this ignition on warning.

WARNING: Disconnect the 12-volt battery wait two minutes before proceeding, remove the ORC fuses, connect the 12-volt battery, wait two minutes before proceeding. Cycle the ignition to the On position, then reconnect the ORC fuses. Wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
If the vehicle is equipped with the standard key ignition, follow this ignition on warning.

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. Measure the voltage between ground and the (R283) Occupant Detector Signal Circuit at the appropriate terminal of the ORC module body harness connector C1-B.

Is there any voltage present?

Yes

- NOTE: The ODS sensor is to be replaced whenever a short to voltage fault has been found in the ODS harness even after the harness repair has been performed.

- 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.

- Repair the short to voltage in the (R283) Passenger Occupant Detector Signal Circuit located between the passenger inline underseat connector and the Passenger Occupant Detector Sensor connector.
- Replace the ODS sensor. Occupant Detection Sensor - Removal.
- Perform the RESTRAINTS SYSTEM VERIFICATION TEST. Restraints System Verification Test.

No

- Go To 5

5. CHECK THE (R283) PASSENGER OCCUPANT DETECTOR SENSOR SIGNAL CIRCUIT AND (R284) PASSENGER OCCUPANT DETECTOR SENSOR RETURN CIRCUIT FOR AN OPEN OR HIGH RESISTANCE BETWEEN THE ORC AND THE PASSENGER SEAT INLINE UNDERSEAT HARNESS CONNECTOR

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 passenger inline underseat harness connector.
2. Measure the resistance of the (R283) Occupant Detector Sensor Signal circuit from the appropriate terminal of the passenger inline underseat connector to the C1-B 55 terminal of the ORC module body harness connector.
3. Measure the resistance of the (R284) Occupant Detector Sensor Return circuit from the appropriate terminal of the passenger inline underseat connector to the C1-B 56 terminal of the ORC module body harness connector.

Is the resistance for either circuit below 1.0 Ohm?

Yes

- Go To 6

No

- Repair the (R283) Occupant Detector Sensor Signal circuit or (R284) Occupant Detector Sensor Return circuit for an open or high resistance.
- Perform the RESTRAINTS SYSTEM VERIFICATION TEST. Restraints System Verification Test.

6. CHECK THE (R283) PASSENGER OCCUPANT DETECTOR SENSOR SIGNAL CIRCUIT AND (R284) PASSENGER OCCUPANT DETECTOR RETURN CIRCUIT FOR AN OPEN OR HIGH RESISTANCE IN THE SEATBACK JUMPER HARNESS

NOTE: Confirm the connector is seated firmly and the lock tab is fully seated.

1. Connect the Occupant Detector Sensor (ODS), verify all in-line connections are secure.
2. Measure the resistance of the (R283) Passenger Occupant Detector Signal circuit to the (R284) Passenger Occupant Detector Sensor Return circuit at the appropriate terminals of the ORC module body harness connector C1-B.

Is the resistance below 700 Ohms?

Yes

- If the vehicle is equipped with the keyless ignition, follow this ignition on warning. WARNING: Disconnect the 12-volt battery wait two minutes before proceeding, remove the ORC fuses, connect the 12-volt battery, wait two minutes before proceeding. Cycle the ignition to the On position, then reconnect the ORC fuses. Wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
If the vehicle is equipped with the standard key ignition, follow this ignition on warning. 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.

- Turn the ignition Off and wait 15 seconds before turning the ignition On.
- Wait one minute and read active codes.
- If the B2734-12-Passenger Occupant Detection Sensor Circuit - Short To Battery DTC becomes active, replace the ORC. Occupant Restraint Controller - Removal.

No

- Go To 8

8. CHECK OPERATION OF THE PASSENGER OCCUPANT DETECTOR SENSOR

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. Replace the Passenger Occupant Detector Sensor. Occupant Detection Sensor - Removal.
2. Remove any special tools or jumper wires and reconnect all previously disconnected components - except the Battery.If the vehicle is equipped with the keyless ignition, follow this ignition on warning.

WARNING: Disconnect the 12-volt battery wait two minutes before proceeding, remove the ORC fuses, connect the 12-volt battery, wait two minutes before proceeding. Cycle the ignition to the On position, then reconnect the ORC fuses. Wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
If the vehicle is equipped with the standard key ignition, follow this ignition on warning.

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.

3. Connect the scan tool to the Data Link Connector - use the most current software available.
4. Use the scan tool and erase the ORC stored codes.
5. Turn the Ignition Off and wait 15 seconds before turning the Ignition On.
6. Wait one minute and read active codes and if there are none present read the stored codes.

Does the scan tool display active B2734-12-PASSENGER OCCUPANT DETECTION SENSOR CIRCUIT - SHORT TO BATTERY DTC?

Yes

- 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.

- 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 ORC. Occupant Restraint Controller - Removal.
- Perform the RESTRAINTS SYSTEM VERIFICATION TEST. Restraints System Verification Test.

No

- Repair is complete.
- Perform the RESTRAINTS SYSTEM VERIFICATION TEST. Restraints System Verification Test.