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Pinpoint Test Bf: U0136

  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
    PCM U0136:00 Lost Communication With Differential Control Module - Rear: No Sub Type Information This DTC sets when messages are missing from the Secondary Inverter System Controller (S-ISC) SOBDMB.
    BECM U0136:00 Lost Communication With Differential Control Module - Rear: No Sub Type Information This DTC sets when messages are missing from the Secondary Inverter System Controller (S-ISC) SOBDMB.
    IPC U0136:00 Lost Communication With Differential Control Module - Rear: No Sub Type Information This DTC sets when messages are missing from the Secondary Inverter System Controller (S-ISC) SOBDMB.
    APIM U0136:00 Lost Communication With Differential Control Module - Rear: No Sub Type Information This DTC sets when messages are missing from the Secondary Inverter System Controller (S-ISC) SOBDMB.
    PAM U0136:00 Lost Communication With Differential Control Module - Rear: No Sub Type Information This DTC sets when messages are missing from the Secondary Inverter System Controller (S-ISC) SOBDMB.
    BCM U0136:00 Lost Communication With Differential Control Module - Rear: No Sub Type Information This DTC sets when messages are missing from the Secondary Inverter System Controller (S-ISC) SOBDMB.
    BCMC U0136:00 Lost Communication With Differential Control Module - Rear: No Sub Type Information This DTC sets when messages are missing from the Secondary Inverter System Controller (S-ISC) SOBDMB.
    DCDC U0136:00 Lost Communication With Differential Control Module - Rear: No Sub Type Information This DTC sets when messages are missing from the Secondary Inverter System Controller (S-ISC) SOBDMB.
    SOBDMC U0136:00 Lost Communication With Differential Control Module - Rear: No Sub Type Information This DTC sets when messages are missing from the Secondary Inverter System Controller (S-ISC) SOBDMB.

    Possible Sources 

    • Communications network concern
    • Secondary Inverter System Controller (S-ISC) SOBDMB

  2. BF1 CARRY OUT THE NETWORK TEST

    NOTE: Do not use dielectric grease in the Secondary Inverter System Controller (S-ISC) connector.

    • When using FDRS, the scan tool attempts to communicate with the ECM first. After establishing communication with the ECM, the scan tool then attempts to communicate with all modules on the vehicle. If an FDRS session cannot be established, FDRS may state no communication can be established with the ECM:

      • Choose No when the scan tool prompts whether or not to retry communication.
      • Enter a ECM part number, tear tag or calibration number to identify the vehicle and start a session. The ECM part number and 4- character tear tag are located on the ECM.

    • Ignition ON.

    Is the Secondary Inverter System Controller (S-ISC) the only module offline? 

    Yes  GO to  BF2
    No  DIAGNOSE the network concern. REFER to: Controller Area Network (CAN) Module Communications Network .

  3. BF2 UPDATE THE SECONDARY INVERTER SYSTEM CONTROLLER (S-ISC) SOFTWARE

    • Attempt to update the Secondary Inverter System Controller (S-ISC) software, regardless of whether the ISC responds to the network tool

    Was the Secondary Inverter System Controller (S-ISC) software update successful? 

    Yes  CLEAR the DTCs and REPEAT the self-test. If DTC U0136 returns. GO to  BF3
    If DTC U0136 does not return, The system is operating correctly at this time. The DTC may have been set due the software being erased.
    No  GO to  BF3

  4. BF3 CHECK FOR AN INTERMITTENT CONCERN

    NOTE: Do not use dielectric grease in the Secondary Inverter System Controller (S-ISC) connector.

    • Using a diagnostic scan tool, refer to the snapshot data to determine when the fault occurs. Determine if the fault occurs during the following conditions:

      • During power-up
      • While driving
      • Temperature of vehicle

    • Attempt to duplicate the concern.

    Can the fault be duplicated? 

    Yes  GO to  BF4
    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.

  5. BF4 CHECK THE SECONDARY INVERTER SYSTEM CONTROLLER (S-ISC) VPWR CIRCUITS FOR VOLTAGE

    NOTE: Do not use dielectric grease in the Secondary Inverter System Controller (S-ISC) connector.

    • Ignition OFF.

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

    • Ignition ON.

    • Measure and record:
      Positive Lead Measurement / Action Negative Lead
      C1458A-M1
      GFD609107Courtesy of FORD MOTOR COMPANY
      		 Ground
      C1458A-M2
      GFD609107Courtesy of FORD MOTOR COMPANY
      		 Ground
      C1458A-L2
      GFD609107Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the voltage within 1.5 volts of battery voltage? 

    Yes  GO to  BF5
    No  With the aid of the OEM WIRING DIAGRAMS , REPAIR the circuit. CLEAR the DTCs and REPEAT the self-test.

  6. BF5 INSPECT THE GROUND CIRCUITS

    NOTE: Do not use dielectric grease in the Secondary Inverter System Controller (S-ISC) connector.

    • Ignition OFF.

    • Disconnect and inspect ground circuit G302 for corrosion or loose connections.

    Is a concern present? 

    Yes  Repair as necessary. CLEAR the DTCs and REPEAT the self-test.
    No  GO to  BF6

  7. BF6 CHECK THE SECONDARY INVERTER SYSTEM CONTROLLER (S-ISC) GROUND CIRCUITS

    NOTE: Do not use dielectric grease in the Secondary Inverter System Controller (S-ISC) connector.

    • Ignition OFF.

    • Measure and record:
      Positive Lead Measurement / Action Negative Lead
      C1458A-L4
      GFD608930Courtesy of FORD MOTOR COMPANY
      		 Ground
      C1458A-M4
      GFD608930Courtesy of FORD MOTOR COMPANY
      		 Ground

    Are the resistances less than 3 ohms on both pins? 

    Yes  GO to  BF8
    No  With the aid of the OEM WIRING DIAGRAMS , REPAIR the open circuit. CLEAR the DTCs and REPEAT the self-test.

  8. BF7 CHECK THE SECONDARY INVERTER SYSTEM CONTROLLER (S-ISC) VPWR CIRCUITS FOR A SHORT TO VOLTAGE

    NOTE: Do not use dielectric grease in the Secondary Inverter System Controller (S-ISC) connector.

    • Disconnect BCMC C1053.

    • Ignition ON.

    • Measure and record:
      Positive Lead Measurement / Action Negative Lead
      C1458A-L2
      GFD609107Courtesy of FORD MOTOR COMPANY
      		 Ground
      C1458A-M2
      GFD609107Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is any voltage present? 

    Yes  With the aid of the OEM WIRING DIAGRAMS , REPAIR the short circuit. CLEAR the DTCs and REPEAT the self-test.
    No  GO to  BF8

  9. BF8 CHECK THE SECONDARY INVERTER SYSTEM CONTROLLER (S-ISC) CAN (CONTROLLER AREA NETWORK) CIRCUITS

    NOTE: Do not use dielectric grease in the Secondary Inverter System Controller (S-ISC) connector.

    • Ignition OFF.

    • Disconnect GWM C2431A.

    • Measure and record:
      Positive Lead Measurement / Action Negative Lead
      C1458A-F1
      GFD608930Courtesy of FORD MOTOR COMPANY
      C1458A-G1
      GFD608930Courtesy of FORD MOTOR COMPANY
      		 C2431A-20

    Is the resistance less than 5 ohms? 

    Yes  GO to  BF10
    No  With the aid of the OEM WIRING DIAGRAMS , REPAIR the open circuit. CLEAR the DTCs and REPEAT the self-test.

  10. BF9 CHECK THE SECONDARY INVERTER SYSTEM CONTROLLER (S-ISC) PCMRC CIRCUIT FOR VOLTAGE

    NOTE: Do not use dielectric grease in the Secondary Inverter System Controller (S-ISC) connector.

    • Ignition ON.

    • Measure and record:
      Positive Lead Measurement / Action Negative Lead
      C1458A-K2
      GFD609107Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the voltage within 1.5 volts of battery voltage? 

    Yes  GO to  BF11
    No  With the aid of the OEM WIRING DIAGRAMS , REPAIR the circuit. CLEAR the DTCs and REPEAT the self-test.

  11. BF10 CHECK THE SECONDARY INVERTER SYSTEM CONTROLLER (S-ISC) CONNECTORS

    NOTE: Do not use dielectric grease in the Secondary Inverter System Controller (S-ISC) connector.

    • Disconnect and inspect all the Secondary Inverter System Controller (S-ISC) connectors.

    • Visually inspect for:

      • Spread or loose terminals
      • Corrosion
      • Damaged, bent or pushed out pins

    Is a concern present? 

    Yes  REPAIR as necessary. CLEAR the DTCs and REPEAT the self-test.
    No  GO to  BF11

  12. BF11 CHECK THE SECONDARY INVERTER SYSTEM CONTROLLER (S-ISC) FOR CORRECT OPERATION

    NOTE: Do not use dielectric grease in the Secondary Inverter System Controller (S-ISC) connector.

    • Reconnect all previously disconnected connectors and make sure they seat correctly.

    • Reconnect all the Secondary Inverter System Controller (S-ISC) connectors and make sure they seat and latch correctly.

    • Using a diagnostic scan-tool, clear the DTCs in the module reporting DTC U0136.

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

    Is DTC U0136 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, Secondary Inverter System Controller (S-ISC), REFER to: Inverter System Controller [SOBDMB] .
    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.
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