DYNAMIC RADAR CRUISE CONTROL SYSTEM, Diagnostic DTC:C1A41

DTC Code DTC Name
C1A41 Brake Request Value Mismatch between ENG / EHV and Driving Support ECU

DESCRIPTION

The brake booster with master cylinder assembly (skid control ECU) receives brake control request signals from the EV control ECU and driving support ECU assembly.

When the request signals received from the EV control ECU and driving support ECU assembly are not consistent, the brake booster with master cylinder assembly (skid control ECU) determines that a malfunction has occurred and sends a malfunction signal to the driving support ECU assembly.

If the driving support ECU assembly receives a malfunction signal, DTC C1A41 is output. Although the brake booster with master cylinder assembly (skid control ECU) sends a malfunction signal to the driving support ECU assembly, the electronically controlled brake system does not output a relevant malfunction detection DTC.

DTC No. Detection Item DTC Detection Condition Trouble Area
C1A41 Brake Request Value Mismatch between ENG / EHV and Driving Support ECU While the power switch is on (IG) and the vehicle speed is 36 km/h (22.5 mph) or more, the brake booster with master cylinder assembly (skid control ECU) detects a significant difference in the brake request signal from the EV control ECU and driving support ECU assembly for 3 seconds or more.

  • Electronically controlled brake system

  • Hybrid control system

  • EV control ECU

  • Brake booster with master cylinder assembly (skid control ECU)

  • Driving support ECU assembly

CAUTION / NOTICE / HINT

Note


  • When replacing the driving support ECU assembly, make sure to replace it with a new one. If a device which was installed to another vehicle is used, the information stored in the driving support ECU assembly will not match the information from the vehicle, and as a result, a DTC may be stored.

  • The dynamic radar cruise control system uses the CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the dynamic radar cruise control system after confirming that the communication systems are functioning properly.

    Click here

  • Perform Registration (VIN registration) when replacing the EV control ECU.

    Click here

PROCEDURE


  1. CHECK FOR DTC (ELECTRONICALLY CONTROLLED BRAKE SYSTEM)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Chassis / ABS/VSC/TRC / Trouble Codes.

    5. Check for DTCs.

      Click here


      Chassis > ABS/VSC/TRC > Trouble Codes
      Result
      Result Proceed to
      Electronically controlled brake system DTCs are not output A
      Electronically controlled brake system DTCs are output B

    B

    GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM Click here

    A

  2. CHECK FOR DTC (HYBRID CONTROL SYSTEM)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

    5. Check for DTCs.

      Click here


      Powertrain > EV > Trouble Codes
      Result
      Result Proceed to
      Hybrid control system DTCs are not output A
      Hybrid control system DTCs are output B

    B

    GO TO HYBRID CONTROL SYSTEM Click here

    A

  3. REPLACE EV CONTROL ECU


    1. Replace the EV control ECU.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  4. CHECK FOR DTC


    1. Clear the DTCs.

      Click here


      Powertrain > Radar Cruise > Clear DTCs

    2. Make sure that the DTC detection conditions are met.

      Tech Tips

      If the detection conditions are not met, the system cannot detect the malfunction.

    3. Check for DTCs.

      Click here


      Powertrain > Radar Cruise > Trouble Codes
      Result
      Result Proceed to
      DTC C1A41 is output A
      DTC C1A41 is not output B

    B

    END (HYBRID VEHICLE CONTROL ECU WAS DEFECTIVE)

    A

  5. REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY (SKID CONTROL ECU)


    1. Replace the brake booster with master cylinder assembly (skid control ECU) with a new one.

      for LHD: Click here

      for RHD: Click here

      Result
      Proceed to
      NEXT

    NEXT

  6. CHECK FOR DTC


    1. Clear the DTCs.

      Click here


      Powertrain > Radar Cruise > Clear DTCs

    2. Make sure that the DTC detection conditions are met.

      Tech Tips

      If the detection conditions are not met, the system cannot detect the malfunction.

    3. Check for DTCs.

      Click here


      Powertrain > Radar Cruise > Trouble Codes
      Result
      Result Proceed to
      DTC C1A41 is not output A
      DTC C1A41 is output (for LHD) B
      DTC C1A41 is output (for RHD) C

    A

    END (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY [SKID CONTROL ECU] WAS DEFECTIVE)

    B

    REPLACE DRIVING SUPPORT ECU ASSEMBLY Click here

    C

    REPLACE DRIVING SUPPORT ECU ASSEMBLY Click here