Ford Fiesta Quiz
Body and Paint

Pinpoint Test - DTC: F. Diagnosis and Testing

In this manual: Body and Paint
Service Information — 27Suspension — 48Transmission — 9Brake System — 52Steering — 21Engine — 140Manual Transmission, Clutch, Transfer Case and Power Transfer Unit — 48Exhaust System — 6Fuel System — 21Climate Control System — 58Instrumentation and Warning Systems — 26Battery and Charging System — 20Infotainment Systems — 41Lighting — 29Power Distribution — 11Electronic Function Group — 30Body and Paint — 275Frame and Mounting — 3
~11min read

B0050:11, B0050:12, B0050:13 and B0050:1D


For circuit and connector information, refer to Wiring Diagrams Cell 46.

Normal Operation and Fault Symptoms

The RCM monitors the driver seatbelt switch circuits for the following faults:

  • Open circuit
  • Short to voltage
  • Short to Ground
  • Current out of range
  • Driver Seat Belt Buckle Switch Faulty

When a fault is detected, the RCM stores DTC B0050:11, B0050:12, B0050:13 or B0050:1D in memory and sends a message to the IPC to illuminate the airbag warning indicator.


DTC Fault Trigger Conditions


Trouble Code Description Fault Trigger Conditions
B0050:11 Driver Seat Belt Sensor: Short to Ground The fault is indicated when the RCM detects a short to ground in the driver seatbelt switch circuit.
B0050:12 Driver Seat Belt Sensor: Short to Battery The fault is indicated when the RCM detects a short to battery voltage in the driver seatbelt switch circuit.
B0050:13 Driver Seat Belt Sensor: Open Circuit The fault is indicated when the RCM detects an open in the driver seatbelt switch circuit.
B0050:1D Driver Seat Belt Sensor: Circuit Current Out of Range The fault is indicated when the RCM detects that the current between the driver seatbelt switch circuits is out of range.

Possible Causes

  • Wiring, Terminals or Connectors
  • Driver Seat Belt Buckle
  • RCM

Visual Inspection and Preliminary Diagnosis

  • Inspect the driver seat belt buckle for damage.
  • Inspect the wiring harness for damage.
  • Inspect the connectors for loose or damaged terminals.

PINPOINT TEST A: B0050:11, B0050:12, B0050:13 AND B0050:1D
NOTE: Most concerns are related to connector and/or wiring issues. Perform a thorough inspection and check before proceeding to the Pinpoint Test.
NOTE: Only disconnect or reconnect SRS components when instructed to do so in the Pinpoint Test step. Failure to follow this instruction may result in an incorrect SRS diagnosis.
NOTE: Always verify the correct SRS component is installed. Parts released for other vehicles may be incompatible even if they appear physically similar. Check the part number listed in the Ford parts catalog to confirm the correct component is installed. If an incorrect SRS component is installed, diagnostic trouble codes (DTCs) may be set.
NOTE: Before returning the vehicle to the customer, the SRS must be fully functional and operating correctly.
A1 REMOVE RCM (RESTRAINTS CONTROL MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • WARNING: Before starting any service procedure in this section, refer to the Safety Warnings in Section 100-00 General Information. Failure to follow this instruction may result in serious personal injury.
    REFER TO: Pyrotechnic Device Handling Precautions (100-00 General Information, Description and Operation).
  • The ignition is on.
  • Using the diagnostic scanner, perform the RCM self-test.

Was DTC B0050:11, B0050:12, B0050:13 or B0050:1D retrieved on demand during the self-test?
Yes This fault cannot be cleared until it is repaired and the DTC is no longer retrieved on demand during the self-test.
If DTC B0050:11 or B0050:1D, GO to A2.
For DTC B0050:12, GO to A4.
For DTC B0050:13, GO to A5.
No This is an intermittent fault when it is present only as a Continuous Memory Diagnostic Trouble Code (CMDTC). GO to A10.
A2 CHECK THE DRIVER SEAT BELT SENSOR DTC (DIAGNOSTIC TROUBLE CODE) TO CHANGE THE FAULT STATUS (SHORT TO GROUND OR CURRENT OUT OF SPECIFIED RANGE)
  • Ignition OFF.
  • De-power the SRS.
    REFER to: Supplemental Restraint System (SRS) Disabling and Re-enabling (501-20B Supplemental Restraint System, General Procedures).
  • Disconnect: Driver Seat Belt Buckle C3065.
  • Reset the SRS. Do not check the SRS at this time.
    REFER TO: Supplemental Restraint System (SRS) Disarming and Rearming (501-20B Supplemental Restraint System, General Procedures).
  • The ignition is on.
  • Using the diagnostic scanner, perform the RCM self-test.
  • DIAGNOSTIC TIP: When reviewing Diagnostic Trouble Codes (DTCs) with the driver seat belt buckle switch disconnected, an open circuit fault is usually cleared.

Did the on-demand DTC change from B0050:11 or B0050:1D to B0050:13?
Yes GO to A8
No For DTC B0050:11, GO to A3.
For DTC B0050:1D, GO to A9.
A3 CHECK THE DRIVER SEAT BELT BUCKLE SWITCH CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • De-power the SRS.
    REFER to: Supplemental Restraint System (SRS) Disabling and Re-enabling (501-20B Supplemental Restraint System, General Procedures).
  • Disconnect: RCM C310A and C310B.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C3065-2 Ground

Is the resistance greater than 10000 Ohms?
Yes GO to A9
No REPAIR the circuit.
For wiring diagrams and connector information, refer to Wiring Diagrams, Cell 5.
GO to A11.
A4 CHECK THE DRIVER SEAT BELT BUCKLE SWITCH CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • De-power the SRS.
    REFER to: Supplemental Restraint System (SRS) Disabling and Re-enabling (501-20B Supplemental Restraint System, General Procedures).
  • Disconnect: RCM C310A and C310B.
  • Disconnect: Driver Side Airbag C367.
  • Disconnect: Driver Seat Belt Buckle C3065.
  • Reset the SRS. Do not check the SRS at this time.
    REFER TO: Supplemental Restraint System (SRS) Disarming and Rearming (501-20B Supplemental Restraint System, General Procedures).
  • The ignition is on.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C3065-2 Ground

Is there voltage present?
Yes REPAIR the circuit.
For wiring diagrams and connector information, refer to Wiring Diagrams, Cell 5.
GO to A11.
No GO to A9
A5 CHECK THE DRIVER SEAT BELT SENSOR DTC (DIAGNOSTIC TROUBLE CODE) TO CHANGE THE FAULT STATUS (OPEN CIRCUIT INDICATED)
  • Ignition OFF.
  • De-power the SRS.
    REFER to: Supplemental Restraint System (SRS) Disabling and Re-enabling (501-20B Supplemental Restraint System, General Procedures).
  • Disconnect: Driver Side Airbag C367.
  • Disconnect: Driver Seat Belt Buckle C3065.
  • Connect a fused jumper wire:
    Click to display connectors
    Lead 1 Measurement/Action Lead 2
    C3065-2 C3065-1
  • Reset the SRS. Do not check the SRS at this time.
    REFER TO: Supplemental Restraint System (SRS) Disarming and Rearming (501-20B Supplemental Restraint System, General Procedures).
  • The ignition is on.
  • Using the diagnostic scanner, perform the RCM self-test.
  • DIAGNOSTIC TIP: When reviewing Diagnostic Trouble Codes (DTCs) with the driver seat belt buckle switch circuits shorted together, a short to ground is usually cleared.

Did the on-demand DTC change from B0050:13 to B0050:11?
Yes REMOVE the fuse jumper and GO to A8.
No REMOVE the fuse jumper and GO to A6.
A6 CHECK THE DRIVER SEAT BELT BUCKLE SWITCH CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • De-power the SRS.
    REFER to: Supplemental Restraint System (SRS) Disabling and Re-enabling (501-20B Supplemental Restraint System, General Procedures).
  • Disconnect: RCM C310A and C310B.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C310B-54 C3065-2

Is the resistance less than 0.5 Ohms?
Yes GO to A7
No REPAIR the circuit.
For wiring diagrams and connector information, refer to Wiring Diagrams, Cell 5.
GO to A11.
A7 CHECK THE DRIVER SEAT BELT BUCKLE SWITCH GROUND CIRCUIT FOR AN OPEN
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C3065-1 C310B-53

Is the resistance less than 3 ohms?
Yes GO to A9
No REPAIR the circuit.
For wiring diagrams and connector information, refer to Wiring Diagrams, Cell 5.
GO to A11.
A8 CONFIRM THE DRIVER SEAT BELT BUCKLE SWITCH FAULT
  • Ignition OFF.
  • De-power the SRS.
    REFER to: Supplemental Restraint System (SRS) Disabling and Re-enabling (501-20B Supplemental Restraint System, General Procedures).
  • Before reconnecting any previously disconnected SRS component:
    • inspect the connector(s) (including any integral connectors) for pushed-out, loose or spread terminals, and loose or chafed wire connections at the terminals.
    • inspect the wiring harness for damage, pinching, or cut or pierced wires.
    • check the RCM C310A and C310B connector position assurance (CPA) lever/latch for proper operation.
    • repair any problems found.
      Refer to Wiring Diagrams Cell 5 for schematic and connector information.
  • Connect: RCM C310A and C310B.
  • Connect: Driver Side Airbag C367.
  • Connect: Driver Seat Belt Buckle C3065.
  • Reset the SRS. Do not check the SRS at this time.
    REFER TO: Supplemental Restraint System (SRS) Disarming and Rearming (501-20B Supplemental Restraint System, General Procedures).
  • The ignition is on.
  • Using the diagnostic scanner, perform the RCM self-test.

Was the original DTC retrieved on demand during the self-test?
Yes INSTALL a new driver seat belt buckle.
REFER TO: Front Seat Belt Buckle (501-20A Seat Belt Systems, Removal and Installation).
GO to A11.
No During diagnosis, the fault condition became intermittent. At this time, do not install any new SRS components. Install SRS components only when directed by the pinpoint test. GO to A10.
A9 CONFIRM RCM (RESTRAINTS CONTROL MODULE) FAULT
  • Ignition OFF.
  • De-power the SRS.
    REFER to: Supplemental Restraint System (SRS) Disabling and Re-enabling (501-20B Supplemental Restraint System, General Procedures).
  • Before reconnecting any previously disconnected SRS component:
    • inspect the connector(s) (including any integral connectors) for pushed-out, loose or spread terminals, and loose or chafed wire connections at the terminals.
    • inspect the wiring harness for damage, pinching, or cut or pierced wires.
    • check the RCM C310A and C310B connector position assurance (CPA) lever/latch for proper operation.
    • repair any problems found.
      Refer to Wiring Diagrams Cell 5 for schematic and connector information.
  • Connect: RCM C310A and C310B.
  • Connect: Driver Side Airbag C367.
  • Connect: Driver Seat Belt Buckle C3065.
  • Reset the SRS. Do not check the SRS at this time.
    REFER TO: Supplemental Restraint System (SRS) Disarming and Rearming (501-20B Supplemental Restraint System, General Procedures).
  • The ignition is on.
  • Using the diagnostic scanner, perform the RCM self-test.

Was the original DTC retrieved on demand during the self-test?
Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSB applies to this concern, INSTALL a new RCM.
REFER TO: Restraints Control Module (RCM) (501-20B Supplemental Restraint System, Removal and Installation).
GO to A11.
No During diagnosis, the fault condition became intermittent. At this time, do not install any new SRS components. Install SRS components only when directed by the pinpoint test. GO to A10.
A10 CHECK FOR AN INTERMITTENT FAULT
  • Ignition OFF.
  • De-power the SRS.
    REFER to: Supplemental Restraint System (SRS) Disabling and Re-enabling (501-20B Supplemental Restraint System, General Procedures).
  • Disconnect the driver seat belt buckle C3065.
    • Inspect the connector(s) (including any inline connectors) for corrosion, loose or spread terminals, and loose or worn wire-to-terminal connections.
    • Inspect the wiring harness for damage, pinching, cut or pierced wires.
    • Rectify any concerns found.
      Refer to Wiring Diagrams Cell 05 for schematic and connector information.
  • Inspect the RCM C310A and C310B connector position assurance (CPA) lever/latch for proper operation.
  • Reconnect all previously disconnected components/connectors.
  • Reset the SRS. Do not check the SRS at this time.
    REFER TO: Supplemental Restraint System (SRS) Disarming and Rearming (501-20B Supplemental Restraint System, General Procedures).
  • The ignition is on.
  • Using the diagnostic scanner, perform the RCM self-test.

Was DTC B0050:11, B0050:12, B0050:13 or B0050:1D retrieved on demand during the self-test?
Yes This fault cannot be cleared until it is repaired and the DTC is no longer retrieved on demand during the self-test.
If DTC B0050:11 or B0050:1D, GO to A2.
For DTC B0050:12, GO to A4.
For DTC B0050:13, GO to A5.
No The fault is not present and cannot be recreated at this time. Do not install any new SRS components at this time. Install SRS components only when directed by the pinpoint test. GO to A11.
A11 CHECK THE SUPPLEMENTAL SRS (SUPPLEMENTAL RESTRAINT SYSTEM) DIAGNOSTIC TROUBLE CODES (DTCS)
  • Ignition OFF.
  • Reconnect all SRS components (if previously disconnected).
  • If previously instructed to disable the SRS, re-enable the SRS. Do not check the SRS at this time.
    Refer to: Supplemental Restraint System (SRS) Disabling and Arming (501-20B Supplemental Restraint System, General Procedures).
  • The ignition is on.
  • NOTE: When Restraints is selected in the Self Test menu, DTCs are retrieved from the RCM and OCSM. Using the diagnostic scanner, perform the Restraints Self Test.

Are any RCM and/or OCSM Diagnostic Trouble Codes (DTCs) retrieved on demand during the self-test?
Yes Do not clear any Diagnostic Trouble Codes (DTCs) until all DTCs have been resolved. DIAGNOSE and REPAIR the RCM and/or OCSM DTCs.
Refer to: Supplemental Restraint System (SRS) (501-20B).
No CLEAR the Continuous Memory Diagnostic Trouble Codes (CMDTCs) from all modules. CONFIRM the SRS. Repair is complete. RETURN the vehicle to the customer.

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