PINPOINT TEST AF: DTCs B1A59:01 AND B1A59:11

WARNING: This page is about a different car, the 2010 Mercury Milan, 2010 Lincoln MKZ, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

WARNING: Never probe the electrical connectors on air bag, Safety Canopy® or side air curtain modules. Failure to follow this instruction may result in the accidental deployment of these modules, which increases the risk of serious personal injury or death.

NOTE: Use the correct probe adapter(s) from the Flex Probe Kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the pinpoint test.

NOTE: Supplemental Restraint System (SRS) components should only be disconnected or reconnected when instructed to do so within a pinpoint test step. Failure to follow this instruction may result in incorrect diagnosis of the SRS .

NOTE: Do not install any new OCS system components until directed to do so. OCS system components should only be installed when directed to do so in the pinpoint test.

NOTE: Always make sure the correct SRS component is being installed. Parts released for other vehicles may not be compatible even if they appear physically similar. Check the part number listed in the Ford Catalog Advantage™ to make sure the correct component is being installed. If an incorrect SRS component is installed, DTCs may set.

NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.

AF1 RETRIEVE OCSM DTCs
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - OCSM .
- Was DTC B1A59:01 or B1A59:11 retrieved on-demand during self-test?
- Yes : This fault cannot be cleared until it is corrected and the DTC is no longer retrieved on-demand during self-test. GO to AF2 .
- No : This is an intermittent fault when present as a CMDTC only. GO to AF8.
AF2 CHECK THE SEAT WIRING AND CONNECTORS
- Ignition OFF.
- WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
- Carry out a thorough inspection of the OCS system wiring, terminals and connectors, jumper harness, weight sensor bolt connector and connection, wiring harness routing and the related seat wiring harness and body wiring harness terminals and connectors.
- Were any problems noted?
- Yes : DEPOWER the SRS . Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
  REPAIR the seat connectors and wiring as needed.
  
  Refer to appropriate SYSTEM WIRING DIAGRAMS article for schematic and connector information.
  
  GO to AF9.
- No : For DTC B1A59:11, GO to AF3 .
  For DTC B1A59:01, GO to AF6.
AF3 CHECK THE OUTBOARD OCS WEIGHT SENSOR BOLTS FOR A FAULT STATUS CHANGE (SHORT TO GROUND INDICATED)
NOTE: This pinpoint test step will attempt to change the fault reported by the OCSM by inducing a different fault condition. If the fault reported changes, this indicates the OCSM is functioning correctly and is not the source of the fault.
- Disconnect: OCS Weight Sensor Bolt "A" C3324 and "B" C3325.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - OCSM .
- DIAGNOSTIC TIP: When viewing DTCs with the OCS weight sensor bolts disconnected, numerous sensor circuit faults would normally be retrieved.
- Was DTC B1A59:01 retrieved on-demand during self-test?
- Yes : GO to AF4 .
- No : INSTALL a new outboard weight sensor assembly. REFER to OCCUPANT CLASSIFICATION SENSOR . GO to AF9.
AF4 CHECK THE INBOARD OCS WEIGHT SENSOR BOLTS FOR A FAULT STATUS CHANGE (SHORT TO GROUND INDICATED)
NOTE: This pinpoint test step will attempt to change the fault reported by the OCSM by inducing a different fault condition. If the fault reported changes, this indicates the OCSM is functioning correctly and is not the source of the fault.
- Ignition OFF.
- WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
- Disconnect: OCS Weight Sensor Bolt "C" C3330 and "D" C3331.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - OCSM .
- DIAGNOSTIC TIP: When viewing DTCs with the OCS weight sensor bolts disconnected, numerous sensor circuit faults would normally be retrieved.
- Was DTC B1A59:01 retrieved on-demand during self-test?
- Yes : GO to AF5 .
- No : INSTALL a new inboard weight sensor assembly. REFER to OCCUPANT CLASSIFICATION SENSOR . GO to AF9.

AF5 CHECK THE OCSM VREF CIRCUITS FOR A SHORT TO GROUND

Ignition OFF.
WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
Disconnect: OCSM C3159.

Measure the resistance between a good ground and the following circuits using the chart:

CONNECTOR REFERENCE CHART

Connector	Circuit
C3159-2	CR140 (YE/GN)
C3159-8	CR153 (GN/WH)
C3159-10	CR141 (BN/YE)
C3159-11	LR142 (YE/BU)
C3159-17	CR154 (VT/OG)

Fig 1: Measuring Resistance Between Good Ground

Courtesy of FORD MOTOR CO.

Are the resistances greater than 10,000 ohms?

Yes : GO to AF7.
No : REPAIR the affected circuits. GO to AF9.

AF6 CHECK THE OCSM
- Ignition OFF.
- WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
- Disconnect: OCSM C3159.
- Carry out a thorough visual inspection of the OCSM terminals, connector and harness connector.
- Were any problems noted?
- Yes : REPAIR as necessary. GO to AF9.
- No : GO to AF7 .
AF7 CONFIRM THE OCSM FAULT
NOTE: Make sure all restraint system sensor electrical connectors and the RCM electrical connector are connected before carrying out the self-test. If not, DTCs will be recorded.
- Ignition OFF.
- WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
- Prior to reconnecting any previously disconnected SRS component:
  - inspect connector(s) (including any in-line connectors) for pushed out, loose or spread terminals and loose or frayed wire connections at terminals.
  - inspect wire harness for any damage, pinched, cut or pierced wires.
  - repair any concerns found.
    Refer to appropriate SYSTEM WIRING DIAGRAMS article for schematic and connector information.
- Connect: OCSM C3159 (if previously disconnected).
- Connect: OCS Weight Sensor Bolts C3324, C3325, C3330 and C3331 (if previously disconnected).
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - OCSM .
- Was DTC B1A59:01 or B1A59:11 retrieved on-demand during self-test?
- Yes : INSTALL a new OCSM . REFER to OCCUPANT CLASSIFICATION SYSTEM MODULE (OCSM) . GO to AF9.
- No : In the process of diagnosing the fault, the fault condition has become intermittent. Do not install any new SRS components at this time. SRS components should only be installed when directed to do so in the pinpoint test. GO to AF9.
AF8 CHECK FOR AN INTERMITTENT FAULT
- Ignition OFF.
- WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
- Disconnect the OCS Weight Sensor Bolts C3324, C3325, C3330 and C3331:
  - inspect connector(s) (including any in-line connectors) for corrosion, loose or spread terminals and loose or frayed wire connections at terminals.
  - inspect wire harness for any damage, pinched, cut or pierced wires.
  - repair any concerns found.
    Refer to appropriate SYSTEM WIRING DIAGRAMS article for schematic and connector information.
- Connect: All Previously Disconnected Component(s)/Connector (s).
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - OCSM .
- Was DTC B1A59:01 or B1A59:11 retrieved on-demand during self-test?
- Yes : This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the on-demand self test. GO to AF2.
- 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. Do not install any new SRS components at this time. SRS components should only be installed when directed to do so in the pinpoint test.
  Refer to appropriate SYSTEM WIRING DIAGRAMS article for schematic and connector information.
  
  GO to AF9 .
AF9 CHECK FOR ADDITIONAL DTCs
- Ignition OFF.
- WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
- Reconnect all SRS components (if previously disconnected).
- If previously directed to depower the SRS , repower the SRS . Do not prove out the SRS at this time. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - Restraints.
- NOTE: When selecting Restraints from the Self Test menu, DTCs will be retrieved from the RCM and OCSM .
- Are any RCM and/or OCSM retrieved on-demand during self-test?
- Yes : Do not clear any DTCs until all DTCs have been resolved. GO to the DTC CHARTS for pinpoint test direction.
- No : CLEAR all RCM and OCSM CMDTCs . PROVE OUT the SRS . Repair is complete. RETURN the vehicle to the customer.