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Pinpoint Test R: The Brake Warning Indicator Is Always On

  1. Refer to Instrument Cluster for schematic and connector information.

    Normal Operation and Fault Conditions 

    See Brake Warning Indicator and ABS/Brake/Stability-Traction Control System Indication descriptions and see Brake Fluid Level Switch component description. REFER to: Instrument Panel Cluster (IPC) - System Operation and Component Description .

    If the brake (red) warning indicator request, brake fluid level low message request or parking brake status messages are missing for 5 seconds longer, the IPC defaults the brake warning indicator on.

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    BCM B1048:01 Brake Fluid Level Switch: General Electrical Failure A continuous and on-demand DTC that sets in the BCM when the BCM detects an open on the brake fluid level switch input.
    BCM B1048:7B Brake Fluid Level Switch: Low Fluid Level An on-demand DTC that sets in the BCM if the BCM detects a low brake fluid level input from the brake fluid level switch.
    BCM C1D00:11 Park Brake Apply Switch: Circuit Short To Ground An on-demand DTC that sets in the BCM if the BCM detects a short to ground on the parking brake input circuit.

    Possible Sources 

    • Wiring, terminals or connectors
    • Brake fluid level switch
    • Parking brake position switch
    • Communication concern
    • ABS concern
    • BCM
    • GWM concern
    • IPC

    Visual Inspection and Pre-checks 

    • Inspect the brake fluid level and verify it is full.
    • Inspect the parking brake is fully released.
    • Inspect the base brake system and the parking brake system for correct operation.
    • Inspect the brake fluid level switch connection and check for signs of connector terminal damage, corrosion or pushed-out pins.
    • Inspect the brake fluid level switch wiring for signs of a cut or opened circuit.
    • Inspect the brake fluid level switch for signs of any external damage.

  2. R1 PERFORM THE IPC (INSTRUMENT PANEL CLUSTER) SELF-TEST

    • Ignition ON.

    • Using a diagnostic scan tool, perform the IPC self-test.

    Are any Diagnostic Trouble Codes (DTCs) recorded? 

    Yes  REFER to DTC Chart: Instrument Panel Cluster (IPC) .
    No  GO to  R2

  3. R2 PERFORM THE BCM (BODY CONTROL MODULE) SELF-TEST

    • Using a diagnostic scan tool, perform the BCM self-test.

    Are any Diagnostic Trouble Codes (DTCs) recorded? 

    Yes  For DTC B1048:01, GO to  R8 For DTC B1048:7B, INSTALL a new brake fluid reservoir or master cylinder as required. REFER to: Brake Master Cylinder - 2.3L EcoBoost (201kW/273PS)/2.3L EcoBoost (213kW/290PS) (N3) . For DTC C1D00:11, GO to  R5 For all other Diagnostic Trouble Codes (DTCs), REFER to: Body Control Module (BCM)
    No  GO to  R3

  4. R3 CHECK THE GWM (GATEWAY MODULE A) DIAGNOSTIC TROUBLE CODES (DTCS)

    • Using a diagnostic scan tool, check the GWM Continuous Memory Diagnostic Trouble Codes (CMDTCs).

    Are any Diagnostic Trouble Codes (DTCs) recorded? 

    Yes  REFER to: Communications Network
    No  GO to  R4

  5. R4 PERFORM THE ABS (ANTI-LOCK BRAKE SYSTEM) MODULE SELF-TEST

    • Using a diagnostic scan tool, perform the ABS module self-test.

    Are any Diagnostic Trouble Codes (DTCs) recorded? 

    Yes  REFER to: Anti-Lock Brake System (ABS) and Stability Control
    No  INSTALL a new IPC. Refer to Instrument Panel Cluster (IPC) .

  6. R5 CHECK THE PARKING BRAKE WARNING INDICATOR SWITCH PID (PARAMETER IDENTIFICATION)

    • Using a diagnostic scan tool, view the BCM parking brake position switch PID.

    • Monitor the parking brake PID (PARK_BRK_SW) with the parking brake released.

    Does the PID agree with the parking brake position? 

    Yes  GO to  R12
    No  GO to  R6

  7. R6 CHECK THE PARKING BRAKE POSITION SWITCH

    • Ignition OFF.

    • Disconnect Parking Brake Position Switch C306.

    • Ignition ON.

    • Using a diagnostic scan tool, view the BCM parking brake position switch Parameter Identifications (PIDs).

    • Monitor the parking brake PID (PARK_BRK_SW) with the parking brake released.

    Does the PID indicate the parking brake is released? 

    Yes  INSTALL a new parking brake position switch.
    No  GO to  R7

  8. R7 CHECK THE PARKING BRAKE POSITION SWITCH INPUT CIRCUIT FOR A SHORT TO GROUND

    • Ignition OFF.

    • Disconnect BCM C2280E.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C2280E-47
      GFD604413Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the resistance greater than 10, 000 ohms? 

    Yes  GO to  R12
    No  REPAIR the circuit.

  9. R8 CHECK THE BRAKE FLUID LEVEL SWITCH

    • Ignition OFF.

    • Disconnect Brake Fluid Level Switch C124.

    • Connect a fused jumper wire:
      Lead 1 Measurement / Action Lead 2
      C124-1
      GFD604414Courtesy of FORD MOTOR COMPANY
      		 C124-2

    • Ignition ON.

    Does the brake warning indicator turn on? 

    Yes  REMOVE the fused jumper wire. INSTALL a new brake fluid reservoir or master cylinder as required. REFER to: Brake Master Cylinder - 2.3L EcoBoost (201kW/273PS)/2.3L EcoBoost (213kW/290PS) (N3)
    No  REMOVE the fuse jumper wire. GO to  R9

  10. R9 CHECK THE BRAKE FLUID LEVEL SWITCH GROUND CIRCUIT FOR AN OPEN AT THE BRAKE FLUID LEVEL SWITCH

    • Ignition OFF.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C124-2
      GFD604413Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the resistance less than 3 ohms? 

    Yes  GO to  R10
    No  REPAIR the circuit.

  11. R10 CHECK THE BRAKE FLUID LEVEL SWITCH INPUT CIRCUIT FOR AN OPEN BETWEEN THE BCM (BODY CONTROL MODULE) AND THE BRAKE FLUID LEVEL SWITCH

    • Disconnect BCM C2280F.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C2280F-28
      GFD604413Courtesy of FORD MOTOR COMPANY
      		 C124-1

    Is the resistance less than 3 ohms? 

    Yes  GO to  R11
    No  REPAIR the circuit.

  12. R11 CHECK THE BRAKE FLUID LEVEL SWITCH FOR SHORT TO GROUND AT THE BRAKE FLUID LEVEL SWITCH

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C124-2
      GFD604413Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the resistance greater than 10, 000 ohms? 

    Yes  GO to  R12
    No  REPAIR the circuit.

  13. R12 CHECK FOR CORRECT BCM (BODY CONTROL MODULE) OPERATION

    • Ignition OFF.

    • Disconnect and inspect all BCM connectors.

    • Repair:

      • corrosion (install new connector or terminals - clean module pins)
      • damaged or bent pins - install new terminals/pins
      • pushed-out pins - install new pins as necessary

    • Reconnect the BCM connectors. Make sure they seat and latch correctly.

    • Operate the system and determine if the concern is still present.

    Is the concern still present? 

    Yes  CHECK OASIS for any applicable service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new BCM. Refer to Body Control Module (BCM) .
    No  The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.
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