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DTC U0293-439: Lost Communication with Hybrid Powertrain Control Module [08/2014 - ]: Procedure

  1. CHECK DTC OUTPUT (HEALTH CHECK) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Enter the following menus: System Select / Health Check.
    4. Check if DTCs are output.

      Result

      Result Proceed to
      Only U0293-439 is output or U0293-439 and U0293-449 are also output. A
      Any CAN communication system DTC other than U0293-449 is also output. B
    5. Turn the power switch off.

    B → See step   9 

    A: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - PLUGIN CHARGE CONTROL ECU ASSEMBLY) 
    1. Disconnect connector L136 from the power management control ECU.
    2. Measure the resistance according to the value(s) in the table below.
      GTY379292Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance (Check for Open)

      Tester Connection Switch Condition Specified Condition
      L136-28 (CA4L) - L136-29 (CA4H) Power switch off 108 to 132 Ω

      Standard Resistance (Check for Short)

      Tester Connection Switch Condition Specified Condition
      L136-28 (CA4L) or L136-29 (CA4H) - Body ground and other terminals Power switch off 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Power Management Control ECU)
    3. Connect the power management control ECU connector.

    NG → See step   6 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (AM21, AM22 VOLTAGE) 
    1. Measure the voltage according to the value(s) in the table below.
      GTY331114Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      L135-1 (AM22) - Body ground Power switch off 11 to 14 V
      L136-7 (AM21) - Body ground Power switch off 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Power Management Control ECU)

    NG → See step   7 

    OK: Go to next step 

  4. CHECK POWER MANAGEMENT CONTROL ECU (+B1, +B2 VOLTAGE). Refer to  PROCEDURE - Step 1 

    NG → See step   10 

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - BODY GROUND). Refer to  PROCEDURE - Step 2 

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   11 

  6. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - PLUGIN CHARGE CONTROL ECU ASSEMBLY) 
    1. Disconnect connector L136 from the power management control ECU.
    2. Disconnect connector S31 plugin charge control ECU assembly.
    3. Measure the resistance according to the value(s) in the table below.
      GTY365296Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Power Management Control ECU)      		 *b Rear view of wire harness connector
      (to Plugin Charge Control ECU Assembly)

      Standard Resistance (Check for Open)

      Tester Connection Switch Condition Specified Condition
      L136-28 (CA4L) - S31-13 (CA4L) Power switch off Below 1 Ω
      L136-29 (CA4H) - S31-12 (CA4H) Power switch off Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Switch Condition Specified Condition
      L136-28 (CA4L) or S31-13 (CA4L) - Body ground and other terminals Power switch off 10 kΩ or higher
      L136-29 (CA4H) or S31-12 (CA4H) - Body ground and other terminals Power switch off 10 kΩ or higher
    4. Connect the plugin charge control ECU assembly connector.
    5. Connect the power management control ECU connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   12 

  7. CHECK FUSE (AM2) 
    1. Remove the AM2 fuse from the engine room relay block and junction block assembly.
    2. Measure the resistance according to the value(s) in the table below.
      GTY327094Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      AM2 fuse Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *1 Engine Room Relay Block and Junction Block Assembly
      *2 AM2 Fuse
    3. Install the AM2 fuse.

    NG → REPLACE FUSE (AM2) 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - AM2 FUSE) 
    1. Disconnect connector L135 and L136 from the power management control ECU.
    2. Remove the AM2 fuse from the engine room relay block and junction block assembly.
    3. Measure the resistance according to the value(s) in the table below.
      GTY340323Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *1 Engine Room Relay Block and Junction Block Assembly *2 AM2 Fuse
      *a Rear view of wire harness connector
      (to Power Management Control ECU)      		 - -

      Standard Resistance (Check for Open)

      Tester Connection Switch Condition Specified Condition
      L135-1 (AM22) - 2 (AM2 fuse) Power switch off Below 1 Ω
      L136-7 (AM21) - 2 (AM2 fuse) Power switch off Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Switch Condition Specified Condition
      L135-1 (AM22), L136-7 (AM21) or 2 (AM2 fuse) - Body ground and other terminals Power switch off 10 kΩ or higher
    4. Install the AM2 fuse.
    5. Connect the power management control ECU connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → CHECK POWER SOURCE CIRCUIT 

  9. GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2014 - ] 
  10. CHECK FOR ECU POWER SOURCE CIRCUIT. Refer to  ECU Power Source Circuit [08/2014 - ]  
  11. REPLACE POWER MANAGEMENT CONTROL ECU. Refer to  COMPONENTS [08/2014 - ] 
  12. REPLACE PLUGIN CHARGE CONTROL ECU ASSEMBLY. Refer to  COMPONENTS [08/2014 - ] 
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