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Home >> Toyota >> 2013 >> Prius Plug-in >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Cruise Control Systems >> Dynamic Radar Cruise Control System (Diagnostic Codes & Circuit Tests) (Plug-In) >> Dynamic Radar Cruise Control System >> DTC C1A03: Driving Support ECU Internal Logical Error; DTC C1A06: Stop Light Switch Input Circuit >> Procedure
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DTC C1A03: Driving Support ECU Internal Logical Error; DTC C1A06: Stop Light Switch Input Circuit: Procedure

  1. CHECK FOR DTCs (DTC C1A03 OR C1A06) 
    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 radar cruise control operation is possible.
      2. Turn the cruise control system on using the cruise control switch (ON-OFF button).
      3. Push the cruise control switch to -/SET to begin control of vehicle speed using the cruise control system.
    5. Enter the following menus: Powertrain / Radar Cruise / Trouble Codes.
    6. Check for DTCs.

      Result

      Result Proceed to
      DTC is not output A
      DTC C1A03 or C1A06 is output B

    B → See step   2 

    A → See step   3 

  2. REPLACE DRIVING SUPPORT ECU ASSEMBLY. Refer to  REMOVAL 
  3. USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING