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Pinpoint Test L: P0887

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

    Normal Operation and Fault Conditions 

    REFER to: Electric Powertrain Control - System Operation and Component Description .

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    SOBDMC P0887:00 TCM Power Relay Control Circuit High: No Sub Type Information This DTC sets when a short to power or open is detected on the relay control circuit.

    Possible Causes 

    • Wiring, terminals or connectors
    • BCMC concern

  2. L1 CHECK FOR LOW VOLTAGE BECM (BATTERY ENERGY CONTROL MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)

    NOTE: Turn the ignition OFF for 5 minutes before carrying out the self-test or clearing DTCs.

    NOTE: DTC P0887 may set as a result of a low 12 volt battery concern or loose connections to the 12V battery or ground.
    NOTE: DTCs P0562 and U3003 may set in any module in addition to DTC P0887 set in the Inverter System Controller (ISC). Diagnose all other low 12V DTCs before entering this pinpoint test.

    • Ignition ON.

    • Using a diagnostic scan tool, retrieve all DTC s.

    Are there any DTC s related to the 12V battery present? 

    Yes  DIAGNOSE all 12V battery DTC s.
    No  GO to  L2

  3. L2 CHECK FOR LOW VOLTAGE INVERTER SYSTEM CONTROLLER (ISC) DIAGNOSTIC TROUBLE CODES (DTCS)

    NOTE: The key cycle is very important, the DTC will not clear unless a key cycle is completed.

    • Ignition OFF.

    • Wait 5 minutes.

    • Ignition ON.

    • Using a diagnostic scan tool, clear the Inverter System Controller (ISC) DTC s.

    • Using a diagnostic scan tool, perform the Inverter System Controller (ISC) self-test.

    Is DTC P0887 present in the Inverter System Controller (ISC)? 

    Yes  GO to  L3
    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. L3 CHECK THE BATTERY AND CHARGING SYSTEM

    • Check the battery and charging system voltages. REFER to: SPECIFICATIONS .

    Are the battery and charging system voltages within specification? 

    Yes  GO to  L4
    No  REPAIR as necessary. REFER to: Battery . Clear the inverter System Controller (ISC) DTC s. REPEAT the self-test.

  5. L4 CHECK THE PSR OUT CIRCUIT FOR AN OPEN

    • Ignition OFF.

    • Disconnect Inverter System Controller (ISC) C199A.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C1002 Pin 9
      GFD826402Courtesy of FORD MOTOR COMPANY
      		 C199A Pin 14

    Is the resistance less than 5 ohms? 

    Yes  GO to  L5
    No  With the aid of the wiring diagram, REPAIR the open circuit.

  6. L5 CHECK THE PSR OUT CIRCUIT FOR A SHORT TO GROUND

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C199A Pin 14
      GFD826402Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the resistance greater than 10K ohms? 

    Yes  GO to  L6
    No  With the aid of the wiring diagram, REPAIR the short circuit.

  7. L6 CHECK THE PSR OUT CIRCUIT FOR A SHORT TO VOLTAGE

    • Ignition ON.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C199A Pin 14
      GFD826403Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is any voltage present? 

    Yes  With the aid of the wiring diagram, REPAIR the short circuit.
    No  GO to  L7

  8. L7 CHECK FOR CORRECT INVERTER SYSTEM CONTROLLER (ISC) OPERATION

    • Ignition OFF.

    • Disconnect and inspect all Inverter System Controller (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 Inverter System Controller (ISC) 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  GO to  L8
    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.

  9. L8 INTERMITTENT CHECK

    Access the SOBDMC and monitor the VPWR (V) PID

    • While observing, the PID s carry out the following:

      • Carefully wiggle all accessible wiring and connectors associated with the Inverter System Controller (ISC)
      • Wiggle the Inverter System Controller (ISC) connectors and harnesses
      • Look for sudden changes in voltage when the harness and connectors are wiggled

    Are any concerns present? 

    Yes  REPAIR as necessary. CLEAR the Inverter System Controller (ISC) DTC s. REPEAT the self-test
    No  GO to  L9

  10. L9 CHECK THE INVERTER SYSTEM CONTROLLER (ISC) VPWR CIRCUITS FOR AN OPEN

    • Ignition OFF.

    • Disconnect Inverter System Controller (ISC) C199A.

    Is the resistance less than 5 ohms? 

    Yes  GO to  L10
    No  With the aid of the wiring diagram, REPAIR the open circuit.

  11. L10 CHECK THE INVERTER SYSTEM CONTROLLER (ISC) VPWR CIRCUITS FOR A SHORT TO VOLTAGE

    • Ignition ON.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C199A Pin 39
      GFD826403Courtesy of FORD MOTOR COMPANY
      		 Ground
      C199A Pin 40
      GFD826403Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is any voltage present? 

    Yes  With the aid of the wiring diagram, REPAIR the short circuit.
    No  GO to  L11

  12. L11 CHECK THE INVERTER SYSTEM CONTROLLER (ISC) ISP-R CIRCUIT FOR AN OPEN

    • Ignition OFF.

    Is the resistance less than 5 ohms? 

    Yes  GO to  L12
    No  With the aid of the wiring diagram, REPAIR the open circuit.

  13. L12 CHECK THE INVERTER SYSTEM CONTROLLER (ISC) ISP-R CIRCUIT FOR A SHORT TO VOLTAGE

    • Ignition ON.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C199A Pin 4
      GFD826403Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is any voltage present? 

    Yes  With the aid of the wiring diagram, REPAIR the short circuit.
    No  GO to  L13

  14. L13 CHECK THE INVERTER SYSTEM CONTROLLER (ISC) ISP-R CIRCUIT FOR VOLTAGE

    • Ignition OFF.

    • Connect a 5 amp fused jumper wire between:
      Positive Lead Measurement / Action Negative Lead
      C199A Pin 14
      GFD826692Courtesy of FORD MOTOR COMPANY
      		 Ground

    • Ignition ON.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C199A Pin 39
      GFD826403Courtesy of FORD MOTOR COMPANY
      		 Ground
      C199A Pin 40
      GFD826403Courtesy of FORD MOTOR COMPANY
      		 Ground

    Are the voltages greater than 10.5 V? 

    Yes  REFER to: Powertrain Control Module (PCM) Input and Output Controls .
    Pinpoint Test Z.
    No  INSTALL a new BCMC. REFER to: BODY CONTROL MODULE C (BCMC) .
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