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Home >> Ford >> 2007 >> Edge SEL Plus, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1424 (Supplemental Restraint System) >> Diagnosis And Testing >> Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) >> Pinpoint Test - Occupant Classification System Module (OCSM) >> Pinpoint Test AD: DTC B2909 >> Pinpoint Test Ad: DTC B2909
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Pinpoint Test Ad: DTC B2909

WARNING: This page is about a different car, the 2010 Mercury Mariner and 2010 Ford Escape. 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.
WARNING: Never disassemble or tamper with safety belt buckle/retractor pretensioners or adaptive load limiting retractors or probe the electrical connectors. Failure to follow this instruction may result in the accidental deployment of the safety belt pretensioners or adaptive load limiting retractors which increases the risk of serious personal injury or death.
NOTE: Use the correct probe adapter(s) from the Flex Probe Kit when taking 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: 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™ or equivalent 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.
  1. AD1 RETRIEVE OCSM DTCs 
    • Ignition ON.
    • Enter the following diagnostic mode on the scan tool: Self Test - OCSM  .
    • Enter the following diagnostic mode on the scan tool: DataLogger - OCSM  - View and Record All 2909 Fault PIDs.
      • Refer to PID list in Normal Operation to view 2909 fault PIDs.
    • Do any on-demand 2909 fault PIDs indicate a fault? 
    • Yes:  This fault cannot be cleared until it is corrected and the DTC is no longer retrieved on-demand during self-test.

      For fault PID 2909_31_OD, GO to AD2  .

      For fault PID 2909_28_OD, GO to  AD8.

      For fault PID 2909_30_OD, GO to  AD9.

      For fault PID 2909_29_OD, GO to  AD10.

    • No:  This is an intermittent fault when present as a Continuous Memory Diagnostic Trouble Code (CMDTC) only. GO to  AD13.
  2. AD2 CHECK THE BTS  CIRCUITS FOR A SHORT TO VOLTAGE 
    • Ignition OFF.
    • Depower the SRS  . Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
    • Disconnect: Passenger Seat Side Air Bag Module C3255.
    • Disconnect: BTS  C389.
    • Disconnect: OCSM  C3285 (vehicles with an OE OCS  system).
    • Disconnect: Passenger Seat Harness C340 (vehicles with an OCS  system service kit).
    • Repower the SRS  . Do not  prove out the SRS  at this time. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
    • Ignition ON.
    • Measure the voltage between BTS: 
      • C389-3, circuit RR142 (YE/BU), harness side and ground.
      • C389-1, circuit LR142 (YE/BU), harness side and ground.
        Fig 1: Measuring Voltage Between BTS C389-3, Circuit RR142 (YE/BU), Harness Side And Ground
        G06100129Courtesy of FORD MOTOR CO.
    • Is voltage present on either circuit? 
    • Yes:  REPAIR the affected circuit. GO to  AD14.
    • No:  GO to AD3  .
  3. AD3 CHECK THE BTS  CIRCUITS FOR AN OPEN 
    • Ignition OFF.
    • For vehicles with an OE OCS  system, measure the resistance between OCSM  C3285, harness side and BTS  C389, harness side using the following chart.
      OCSM SPECIFICATION

      OCSM  Circuit BTS
      C3285-11 LR142 (YE/BU) C389-1
      C3285-12 RR142 (GN) C389-3
      - GD183 (BK/WH) C389-2, harness side and ground
      Fig 2: Measuring Resistance Between OCSM C3285, Harness Side And Ground
      G06100124Courtesy of FORD MOTOR CO.
    • For vehicles with an OCS  system service kit, measure the resistance between passenger seat harness C340, harness side and BTS  C389, harness side using the following chart.
      OCSM SPECIFICATION

      OCSM  Circuit BTS 
      C340-15 LR142 (YE/BU) C389-1
      C340-11 RR142 (GN) C389-3
      - GD183 (BK/WH) C389-2, harness side and ground
      Fig 3: Measuring Resistance Between Passenger Seat Harness C340 And BTS C389
      G06383847Courtesy of FORD MOTOR CO.
    • Are the resistances less than 0.5 ohm? 
    • Yes:  GO to AD4  .
    • No:  REPAIR the affected circuit. GO to  AD14.
  4. AD4 CHECK THE BTS  VREF AND SIGNAL CIRCUIT FOR A SHORT TO GROUND 
    • Measure the resistance between BTS: 
      • C389-3, circuit RR142 (GN), harness side and ground.
      • C389-1, circuit LR142 (YE/BU), harness side and ground.
        Fig 4: Measuring Resistance Between BTS And C389-3, Circuit RR142 (GN), Harness Side And Ground
        G06100131Courtesy of FORD MOTOR CO.
    • Are the resistances greater than 10,000 ohms? 
    • Yes:  GO to AD5  .
    • No:  REPAIR circuit LR142 (YE/BU) or RR142 (GN). GO to  AD14.
  5. AD5 CHECK FOR A SHORT BETWEEN BTS CIRCUITS 
    • Measure the resistance between BTS: 
      • C389-3, circuit RR142 (GN), harness side and C389-1, circuit LR142 (YE/BU), harness side.
      • C389-3, circuit RR142 (GN), harness side and C389-2, circuit RR142 (GN), harness side.
      • C389-1, circuit LR142 (YE/BU), harness side and C389- 2, circuit RR142 (GN), harness side.
        Fig 5: Measuring Resistance Between BTS C389-3, Circuit RR142 (GN) And C389-1, Circuit LR142 (YE/BU)
        G06383849Courtesy of FORD MOTOR CO.
    • Are the resistances greater than 10,000 ohms? 
    • Yes:  GO to AD6  .
    • No:  REPAIR the affected circuits. GO to  AD14.
  6. AD6 CHECK THE OCSM OUTPUT 
    • Connect: OCSM  C3285 (vehicles with an OE OCS  system).
    • Connect: Passenger Seat Harness C340 (vehicles with an OCS  system service kit).
    • Ignition ON.
    • Measure the voltage between BTS  C389-1, circuit LR142 (YE/BU), harness side and C389-2, circuit RR142 (GN), harness side.
      Fig 6: Measuring Voltage Between Belt Tension Sensor C389-1 And C389-2
      G06100127Courtesy of FORD MOTOR CO.
    • Is the voltage approximately 5 volts? 
    • Yes:  GO to AD7  .
    • No:  GO to  AD12.
  7. AD7 CHECK BTS VOLTAGE OUTPUT 
    • Ignition OFF.
    • Connect a fused jumper wire between BTS  C389-1, circuit LR142 (YE/BU), harness side and C389 pin 1, component side.
    • Connect a fused jumper wire between BTS  C389-2, circuit RR142 (GN), harness side and C389 pin 2, component side.
    • Ignition ON.
    • Measure the voltage between BTS  C389 pin 3, component side and ground as the tension of the BTS  varies by pulling upward at the safety belt webbing.
      Fig 7: Measuring Voltage Between BTS C389 Pin 3, Component Side And Ground
      G06383851Courtesy of FORD MOTOR CO.
    • Does the voltage vary from approximately 0.95 volt with no tension applied to the sensor to approximately 3.8 volts with full tension applied to the sensor? 
  8. AD8 CHECK THE BTS CIRCUITS FOR A SHORT TO VOLTAGE 
    • Ignition OFF.
    • Depower the SRS  . Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
    • Disconnect: Passenger Seat Side Air Bag Module C3255.
    • Disconnect: BTS  C389.
    • Disconnect: OCSM  C3285 (vehicles with an OE OCS  system).
    • Disconnect: Passenger Seat Harness C340 (vehicles with an OCS  system service kit).
    • Repower the SRS  . Do not  prove out the SRS  at this time. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
    • Ignition ON.
    • Measure the voltage between BTS: 
      • C389-3, circuit RR142 (GN), harness side and ground.
      • C389-1, circuit LR142 (YE/BU), harness side and ground.
        Fig 8: Measuring Voltage Between BTS C389-3, Circuit RR142 (YE/BU), Harness Side And Ground
        G06100129Courtesy of FORD MOTOR CO.
    • Is any voltage present on either circuit? 
    • Yes:  REPAIR the affected circuit. GO to  AD14.
    • No:  GO to  AD12.
  9. AD9 CHECK THE BTS CIRCUIT FOR AN OPEN 
    • Ignition OFF.
    • Depower the SRS  . Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
    • Disconnect: BTS  C389.
    • Disconnect: OCSM  C3285 (vehicles with an OE OCS  system).
    • Disconnect: Passenger Seat Harness C340 (vehicles with an OCS  system service kit).
    • For vehicles with an OE OCS  system, measure the resistance between OCSM  C3285, harness side and BTS  C389, harness side using the following chart.
      OCSM SPECIFICATION

      OCSM  Circuit BTS 
      C3285-11 LR142 (YE/BU) C389-1
      C3285-12 RR142 (GN) C389-3
      - GD183 (BK/WH) C389-2, harness side and ground
      Fig 9: Measuring Resistance Between OCSM C3285, Harness Side And Ground
      G06100124Courtesy of FORD MOTOR CO.
    • For vehicles with an OCS  system service kit, measure the resistance between passenger seat harness C340, harness side and BTS  C389, harness side using the following chart.
      OCSM SPECIFICATION

      OCSM  Circuit BTS 
      C340-15 LR142 (YE/BU) C389-1
      C340-11 RR142 (GN) C389-3
      - GD183 (BK/WH) C389-2, harness side and ground
      Fig 10: Measuring Resistance Between Passenger Seat Harness C340 And BTS C389
      G06383847Courtesy of FORD MOTOR CO.
    • Are the resistances less than 0.5 ohm? 
    • Yes:  GO to  AD11.
    • No:  REPAIR the affected circuit. GO to  AD14.
  10. AD10 CHECK THE BTS CIRCUITS FOR A SHORT TO GROUND 
    • Ignition OFF.
    • Depower the SRS  . Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
    • Disconnect: BTS  C389.
    • Disconnect: OCSM  C3285 (vehicles with an OE OCS  system).
    • Disconnect: Passenger Seat Harness C340 (vehicles with an OCS  system service kit).
    • Measure the resistance between BTS: 
      • C389-3, circuit RR142 (GN), harness side and ground.
      • C389-1, circuit LR142 (YE/BU), harness side and ground.
        Fig 11: Measuring Resistance Between BTS And C389-3, Circuit RR142 (GN), Harness Side And Ground
        G06100131Courtesy of FORD MOTOR CO.
    • Are the resistances greater than 10,000 ohms? 
    • Yes:  GO to  AD12.
    • No:  REPAIR the affected circuit. GO to  AD14.
  11. AD11 CHECK THE OCSM OUTPUT 
    • Disconnect: Passenger Seat Side Air Bag Module C3255.
    • Connect: OCSM  C3285 (vehicles with an OE OCS  system).
    • Connect: Passenger Seat Harness C340 (vehicles with an OCS  system service kit).
    • Repower the SRS  . Do not  prove out the SRS  at this time. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
    • Ignition ON.
    • Measure the voltage between BTS  C389-1, circuit LR142 (YE/BU), harness side and C389-2, circuit RR142 (GN), harness side.
      Fig 12: Measuring Voltage Between Belt Tension Sensor C389-1 And C389-2
      G06100127Courtesy of FORD MOTOR CO.
    • Is the voltage approximately 5 volts? 
    • Yes:  GO to  AD7.
    • No:  GO to AD12  .
  12. AD12 CONFIRM THE OCS SYSTEM FAULT 
    NOTE: Make sure all OCS  system components, restraint system sensor electrical connectors and the RCM  electrical connectors are connected before carrying out self-test. If not, DTCs will be recorded.
    • Ignition OFF.
    • Depower the SRS  . Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING .
    • 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, Connector Repair Procedures for schematic and connector information.

    • Connect: BTS  C389.
    • Connect: OCSM  C3285 (if disconnected previously) (vehicles with an OE OCS  system).
    • Connect: Passenger Seat Harness C340 (if disconnected previously) (vehicles with an OCS  system service kit).
    • 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 - OCSM  .
    • Enter the following diagnostic mode on the scan tool: DataLogger - OCSM  - View and Record All 2909 Fault PIDs.
      • Refer to PID list in Normal Operation to view 2909 fault PIDs.
    • Does the original on-demand 2909 fault PID indicate a fault? 
    • Yes:  INSTALL a new OCS  system service kit. REFER to OCCUPANT CLASSIFICATION SENSOR - SERVICE KIT . GO to  AD14.
    • 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 AD13  .
  13. AD13 CHECK FOR AN INTERMITTENT FAULT 
    • Ignition OFF.
    • Disconnect BTS  C389:
      • inspect connector(s) (including any in-line connectors) for 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, Connector Repair Procedures for schematic and connector information.

    • Connect: BTS  C389.
    • Ignition ON.
    • Enter the following diagnostic mode on the scan tool: Self Test - OCSM  .
    • Enter the following diagnostic mode on the scan tool: DataLogger - OCSM  - View and Record All 2909 Fault PIDs.
      • Refer to PID list in Normal Operation to view 2909 fault PIDs.
    • Do any on-demand 2909 fault PIDs indicate a fault? 
    • Yes:  This is a hard fault. This fault cannot be cleared until it is corrected and the DTC is no longer retrieved on-demand during self-test.

      Using the on-demand fault PIDs recorded, GO to the appropriate pinpoint test step.

      For fault PID 2909_31_OD, GO to  AD2.

      For fault PID 2909_28_OD, GO to  AD8.

      For 2909_30_OD, GO to  AD9.

      For fault PID 2909_29_OD, GO to  AD10.

    • No:  CHECK for causes of the intermittent fault. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition 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.  REPAIR any intermittent wiring, terminal or connector concerns found. GO to AD14  .
  14. AD14 CHECK FOR ADDITIONAL SRS 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 DTCs retrieved? 
    • 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.
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