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Home >> Toyota >> 2013 >> Prius Plug-in >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 77 (Dynamic Radar Cruise Control System (Diagnostic Codes & Circuit Tests) (Except Plug-In)) >> Dynamic Radar Cruise Control System >> DTC C1A40: ENG / EHV Device >> Procedure
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DTC C1A40: ENG / EHV Device: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. READ OUTPUT DTC (HYBRID CONTROL SYSTEM) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.
    5. Read the DTCs.

      Result

      Result Proceed to
      DTC is not output A
      DTC is output B

    B → See step   8 

    A: Go to next step 

  2. READ OUTPUT DTC (SFI SYSTEM) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
    5. Read the DTCs.

      Result

      Result Proceed to
      DTC is not output A
      DTC is output B

    B → See step   10 

    A: Go to next step 

  3. CHECK WHETHER DTC OUTPUT RECURS (DTC C1A40) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    4. Perform the following to make sure that the DTC detection conditions are met.

      HINT: 

      If the detection conditions are not met, the malfunction cannot be detected.

      1. Drive the vehicle at a speed for which cruise control operation is possible.
      2. Turn the cruise control main switch on.
      3. Push the -SET switch to activate the cruise control.
    5. Enter the following menus: Powertrain / Radar Cruise / Trouble Codes.
    6. Read the DTCs.

      Result

      Result Proceed to
      DTC is not output A
      DTC C1A40 is output B

    B → See step   4 

    A → See step   11 

  4. REPLACE POWER MANAGEMENT CONTROL ECU 
    1. Replace the power management control ECU. Refer to REMOVAL .

    NEXT: Go to next step 

  5. CHECK WHETHER DTC OUTPUT RECURS (DTC C1A40) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    4. Perform the following to make sure that the DTC detection conditions are met.

      HINT: 

      If the detection conditions are not met, the malfunction cannot be detected.

      1. Drive the vehicle at a speed for which cruise control operation is possible.
      2. Turn the cruise control main switch on.
      3. Push the -SET switch to activate the cruise control.
    5. Enter the following menus: Powertrain / Radar Cruise / Trouble Codes.
    6. Read the DTCs.

      Result

      Result Proceed to
      DTC is not output A
      DTC C1A40 is output B

    B → See step   6 

    A → END 

  6. REPLACE ECM 
    1. Replace the ECM. Refer to REMOVAL .

    NEXT: Go to next step 

  7. CHECK WHETHER DTC OUTPUT RECURS (DTC C1A40) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    4. Perform the following to make sure that the DTC detection conditions are met.

      HINT: 

      If the detection conditions are not met, the malfunction cannot be detected.

      1. Drive the vehicle at a speed for which cruise control operation is possible.
      2. Turn the cruise control main switch on.
      3. Push the -SET switch to activate the cruise control.
    5. Enter the following menus: Powertrain / Radar Cruise / Trouble Codes.
    6. Read the DTCs.

      Result

      Result Proceed to
      DTC is not output A
      DTC C1A40 is output B

    B → See step   9 

    A → END 

  8. GO TO HYBRID CONTROL SYSTEM. Refer to  DIAGNOSTIC TROUBLE CODE CHART 
  9. REPLACE DRIVING SUPPORT ECU. Refer to  REMOVAL 
  10. GO TO SFI SYSTEM. Refer to  DIAGNOSTIC TROUBLE CODE CHART 
  11. USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 
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