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Pinpoint Test M : The Audio Digital Signal Processing (DSP) Module Does Not Respond To The Diagnostic Scan Tool

WARNING: This page is about a different car, the 2019 Ford Ranger. However, it is still accessible from the selected car via links, so may be relevant.
  1. Refer to Module Communications Network for schematic and connector information. Refer to Audio System/Navigation - SYNC for schematic and connector information.

    Normal Operation and Fault Conditions 

    The DSP communicates with the diagnostic scan tool through the HS-CAN3.

    Possible Sources 

    • Fuse
    • Wiring, terminals and connector
    • DSP

    Visual Inspection and Pre-checks 

    • Verify BCM fuses 5 (20A) and 28 (20A) are OK.

  2. M1 CHECK THE DSP (AUDIO DIGITAL SIGNAL PROCESSING MODULE) VOLTAGE SUPPLY CIRCUITS FOR AN OPEN

    • Ignition OFF.

    • Disconnect: DSP C3041C.

    • Ignition ON.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C3041C-4
      GFD433170Courtesy of FORD MOTOR COMPANY
      Ground
      C3041C-8
      GFD433170Courtesy of FORD MOTOR COMPANY
      Ground

    Are the voltages greater than 11 volts? 

    Yes  GO to  M2
    No  VERIFY BCM fuses 5 (20A) and 28 (20A) are OK. If OK, REPAIR the circuit in question. If not OK, REFER to OEM Electrical Wiring Diagram Introduction to identify the possible causes of the circuit short.
  3. M2 CHECK THE DSP (AUDIO DIGITAL SIGNAL PROCESSING MODULE) GROUND CIRCUITS FOR AN OPEN

    • Ignition OFF.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C3041C-1
      GFD433171Courtesy of FORD MOTOR COMPANY
      Ground
      C3041C-5
      GFD433171Courtesy of FORD MOTOR COMPANY
      Ground

    Are the resistances less than 3 ohms? 

    Yes  GO to  M3
    No  REPAIR the circuit in question.
  4. M3 CHECK THE HS-CAN3 (HIGH-SPEED CONTROLLER AREA NETWORK 3) CIRCUITS BETWEEN THE DSP (AUDIO DIGITAL SIGNAL PROCESSING MODULE) AND THE GWM (GATEWAY MODULE A) FOR AN OPEN

    • Disconnect: GWM C2431.

    • Disconnect: DSP C3041A.

    Are the resistances less than 3 ohms? 

    Yes  GO to  M4
    No  REPAIR the circuit in question.
  5. M4 CHECK FOR CORRECT DSP (AUDIO DIGITAL SIGNAL PROCESSING MODULE) OPERATION

    • Ignition OFF.

    • Disconnect and inspect the DSP 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 DSP 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, General Service Bulletin (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 DSP. REFER to: Audio Digital Signal Processing (DSP) Module .
    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.