Pinpoint Test Q: DTC B229A - Occupant Classification System Contamination

WARNING: This page is about a different car, the 2006 Mercury Milan, 2006 Lincoln Zephyr, and 2006 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION: When installing a new restraints control module (RCM), always make sure the correct RCM is being installed. The RCM 40-pin connector is keyed differently for vehicles with side air curtains and side air bags than the 40-pin connector for vehicles without side air curtains and side air bags. Do not force the 40-pin connector onto the RCM. If the connector is forced onto the RCM, damage to the RCM and/or connector will occur.

NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough Inspection and Verification before proceeding with the pinpoint test.

Q1 CHECK FOR CONTINUOUS OR ON-DEMAND DTCs
WARNING: Restraint system diagnostic tools are for service only. Tools must be removed prior to operating the vehicle over the road. Failure to remove restraint system diagnostic tools could result in injury and possible violation of vehicle safety standards.

WARNING: Never probe the connectors on the air bag module. Doing so can result in air bag deployment, which can result in personal injury.

WARNING: The safety belt pretensioner is a pyrotechnic device. Always wear safety glasses when repairing an air bag equipped vehicle and when handling a safety belt buckle pretensioner or safety belt retractor pretensioner. Never probe a pretensioner electrical connector. Doing so could result in pretensioner or air bag deployment and could result in personal injury.

WARNING: Never probe the electrical connector on a side air curtain module. Doing so can result in side air curtain deployment.

NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
- Enter the following diagnostic mode on the scan tool: OCS Module On-Demand Self Test/Retrieve and Record Continuous Memory DTCs.
- Enter the following diagnostic mode on the scan tool: View and Record DTC B229A Fault PIDs.
- Was on-demand DTC B229A retrieved?
Yes : This is a hard fault. The fault condition is still present. This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the on-demand self test. GO to Q2.

No : This is an intermittent fault when present as a continuous memory DTC only (DTC not retrieved on demand). The fault condition is not present at this time. GO to Q6.
Q2 INSPECT THE OCCUPANT CLASSIFICATION SENSOR
- Key in OFF position.
- Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Remove the passenger seat. Refer to SEATING .
- Inspect the affected occupant classification sensor rail for the presence of any foreign objects.
- Were any problems noted?
Yes : REPAIR as necessary. GO to Q7.

No : GO to Q3.
Q3 CHECK THE OCCUPANT CLASSIFICATION SENSOR RAIL
- Remove the affected occupant classification sensor rail and inspect for the presence of any foreign objects. Refer to OCCUPANT CLASSIFICATION SENSOR .
- Were any problems noted?
Yes : REPAIR as necessary. GO to Q7.

No : GO to Q4.
Q4 INSTALL A NEW OCS RAIL
- Install a new OCS rail. Refer to OCCUPANT CLASSIFICATION SENSOR .
- Install the passenger seat. Refer to SEATING .
- Repower the system. Do not prove out the system at this time. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Enter the following diagnostic mode on the scan tool: OCS Module On-Demand Self Test/Retrieve and Record Continuous Memory DTCs.
- Was on-demand DTC B229A retrieved?
Yes : GO to Q5.

No : Fault corrected. GO to Q7.
Q5 CONFIRM OCS MODULE FAULT
- Key in OFF position.
- Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Remove the passenger seat. Refer to SEATING .
- Install the original OCS rail. Refer to OCCUPANT CLASSIFICATION SENSOR .
- Install the passenger seat. Refer to SEATING .
- Repower the system. Do not prove out the system at this time. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Enter the following diagnostic mode on the scan tool: OCS Module On-Demand Self Test/Retrieve and Record Continuous Memory DTCs.
- Was on-demand DTC B229A retrieved?
Yes : INSTALL a new OCS module. REFER to OCCUPANT CLASSIFICATION MODULE . GO to Q7.

No : CHECK for causes of the intermittent fault. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition key frequently. ACTIVATE other systems in the same wire harness. REPAIR any intermittent concerns found. GO to Q7.
Q6 CHECK FOR AN INTERMITTENT FAULT
- Key in OFF position.
- Enter the following diagnostic mode on the scan tool: OCS Module On-Demand Self Test/Retrieve and Record Continuous Memory DTCs.
- Was on-demand DTC B229A retrieved?
Yes : This is a hard fault. The fault condition is now present. This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the on-demand self test. GO to Q2.

No : CHECK for causes of the intermittent fault. ATTEMPT to recreate the hard fault by moving/positioning the passenger seat. REPAIR any intermittent concerns found. GO to Q5.
Q7 CHECK FOR ADDITIONAL DTCs
- Refer to the OCS module continuous memory DTCs recorded during Step Q1.
- Were any continuous memory DTCs retrieved during Step Q1 ?
Yes : Do not clear any DTCs until all DTCs have been resolved. GO to the SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DIAGNOSTIC TROUBLE CODE (DTC) TABLE for pinpoint test direction.

No : RECONNECT the system. If previously directed to deactivate the system, REACTIVATE the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEACTIVATION AND REACTIVATION . REPOWER the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING . PROVE OUT the system. CLEAR all OCS module and RCM DTCs.