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Pinpoint Test AO: P0C66

  1. NOTE: The Secondary Inverter System Controller (S-ISC) is referred to as the SOBDMB (Secondary On-Board Diagnostic Control Module B) in the scan tool.

    Normal Operation and Fault Conditions 

    REFER to: Front Electric Drive Assembly - System Operation and Component Description .

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    SOBDMB P0C66:00 Generator Position Sensor Circuit "A" Low: No Sub Type Information This DTC sets when a short to ground is detected in the generator resolver circuit.

    Possible Sources 

    • Wiring, terminals or connectors
    • Front electric drive assembly
    • Secondary Inverter System Controller (S-ISC) calibration

  2. AO1 CHECK THE SECONDARY INVERTER SYSTEM CONTROLLER (S-ISC) CALIBRATION LEVEL

    NOTE: Wiring overlays or repinning of circuits are NOT appropriate for DTC P0C66 due to risk of hardware damage.

    • Verify the Secondary Inverter System Controller (S-ISC) is at the latest calibration level.

    Is the Secondary Inverter System Controller (S-ISC) at the latest calibration level? 

    Yes  GO to  AO2
    No  UPDATE the Secondary Inverter System Controller (S-ISC) to the latest calibration level.
  3. AO2 CHECK FOR CMDTC (CONTINUOUS MEMORY DIAGNOSTIC TROUBLE CODE) P0C66

    • Ignition ON.

    • Using a diagnostic scan tool, retrieve all Secondary Inverter System Controller (S-ISC) CMDTCs.

    Was CMDTC P0C66 read from the Secondary Inverter System Controller (S-ISC)? 

    Yes  GO to  AO3
    No  The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.
  4. AO3 VISUAL INSPECTION OF THE LOW VOLTAGE SYSTEM

    • Ignition OFF.

    • Disconnect Secondary Inverter System Controller (S-ISC) C1458A.

    • Visually inspect all the low voltage cables.

    • Make sure all the low voltage connectors are correctly and securely connected.

    • Examine all the low voltage cables and connectors for damaged, burned or overheated insulation and loose or broken conditions.

    Is a concern present? 

    Yes  REPAIR as necessary. CLEAR the Secondary Inverter System Controller (S-ISC) DTCs and REPEAT the self-test.
    No  GO to  AO4
  5. AO4 CHECK THE GS3 CIRCUIT FOR A SHORT TO GROUND

    • Disconnect Front electric drive assembly C1280.

    • Measure and record:
      Positive Lead Measurement / Action Negative Lead
      C1280-3
      GFD608930Courtesy of FORD MOTOR COMPANY
      Ground

    Is the resistance above 10K ohms? 

    Yes  GO to  AO5
    No  REPLACE the harness, CLEAR the Secondary Inverter System Controller (S-ISC) DTCs. REPEAT the self-test.
  6. AO5 CHECK FOR CORRECT SECONDARY INVERTER SYSTEM CONTROLLER (S-ISC) OPERATION

    • Ignition OFF.

    • Disconnect and inspect all Secondary Inverter System Controller (S-ISC) 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 Secondary Inverter System Controller (S-ISC) connectors. Make sure they seat and latch correctly.

    • Connect Front electric drive assembly C1280.

    • Ignition ON.

    • 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, GO to Pinpoint Test V 
    (In step V4 continue through to step V5 regardless of DTC presence.)
    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.