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Pinpoint Tests AF: DTCs B1A59:01 and B1A59:11




Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS)

Refer to Wiring Diagram Set 46 (Fusion/Milan/MKZ, Fusion Hybrid/Milan Hybrid) for schematic and connector information. Diagrams By Number

Pinpoint Test - Supplemental Restraint System (SRS)

Pinpoint Test AF: DTCs B1A59:01 and B1A59:11

Refer to Wiring Diagram Set 46 (Fusion/Milan/MKZ, Fusion Hybrid/Milan Hybrid), Supplemental Restraint System for schematic and connector information. Diagrams By Number

Normal Operation

The Occupant Classification System Module (OCSM) monitors each Occupant Classification Sensor (OCS) weight sensor bolt and circuitry for faults. If the OCSM detects a fault, it will store DTC B1A59:01 in memory and send a message to the Restraints Control Module (RCM).

The RCM will store DTC B00A0:09 in memory and send a message to the Instrument Cluster (IC) module to illuminate the air bag warning indicator.

- DTC B1A59:01 (Sensor 5 Volt Supply: General Electrical Failure) - When the OCSM senses a short between the
Belt Tension Sensor (BTS) VREF circuit and one of the OCS weight sensor bolt VREF circuits, a fault will be indicated.
- DTC B1A59:11 (Sensor 5 Volt Supply: Circuit Short To Ground) - When the OCSM senses a short to ground on any of the OCS weight sensor bolt or BTS VREF circuits, a fault will be indicated.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- OCSM
- OCS weight sensor bolt assembly



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

WARNING: Never probe the electrical connectors on air bag, Safety Canopy(R) 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.

NOTICE: 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.
Inspection and Verification

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(TM) 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.

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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.

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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 Supplemental Restraint System (SRS) Depowering and Repowering.

REPAIR the seat connectors and wiring as needed.
Refer to Wiring Diagram Set 5 (Fusion/Milan/MKZ, Fusion Hybrid/Milan Hybrid), Connector Repair Procedures for schematic and connector information. Diagrams By Number
GO to AF9.

No
For DTC B1A59:11, GO to AF3.

For DTC B1A59:01, GO to AF6.

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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 Service and Repair. GO to AF9.

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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 Service and Repair. GO to AF9.

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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:









- Are the resistances greater than 10,000 ohms?

Yes
GO to AF7.

No
REPAIR the affected circuits. GO to AF9.

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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.

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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 Wiring Diagram Set 5 (Fusion/Milan/MKZ, Fusion Hybrid/Milan Hybrid), Connector Repair Procedures for schematic and connector information. Diagrams By Number

- 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) Service and Repair. 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.

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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 Wiring Diagram Set 5 (Fusion/Milan/MKZ, Fusion Hybrid/Milan Hybrid), Connector Repair Procedures for schematic and connector information. Diagrams By Number

- 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 Wiring Diagram Set 5 (Fusion/Milan/MKZ, Fusion Hybrid/Milan Hybrid), Connector Repair Procedures for schematic and connector information. Diagrams By Number
GO to AF9.

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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 notprove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering 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. [1][2]Diagnostic Trouble Code Descriptions

No
CLEAR all RCM and OCSM CMDTCs. PROVE OUT the SRS. Repair is complete. RETURN the vehicle to the customer.

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