CRUISE CONTROL SYSTEM, Diagnostic DTC:P1578

DTC Code DTC Name
P1578 Brake System Malfunction

DESCRIPTION

This DTC is output when the electronically controlled brake system has a problem. Check the electronically controlled brake system when this DTC is output.

DTC No. DTC Detection Condition Trouble Area
P1578 The power management control ECU receives a brake system error signal for 0.2 sec. or more while the cruise control is in operation Electronically controlled brake system

WIRING DIAGRAM

A003RSCE34

INSPECTION PROCEDURE

Tech Tips

This circuit uses CAN communication. Therefore, if there are any malfunctions in the communication circuit, one or more DTCs in the CAN communication system are output.

PROCEDURE


  1. CHECK DTC (ELECTRONICALLY CONTROLLED BRAKE SYSTEM)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the intelligent tester on.

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

    5. Read the DTC.

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

    B

    GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM Click here

    A

  2. CHECK WHETHER DTC OUTPUT RECORDS (CRUISE CONTROL SYSTEM)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the intelligent tester on.

    4. Perform the following to make sure that the DTC detection conditions are met.

      Tech Tips

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


      1. Drive the vehicle at a speed of 40 km/h (25 mph) or more.

      2. Turn the cruise control switch (ON-OFF button) on.

      3. Push the -SET button to activate the cruise control.

    5. Enter the following menus: Powertrain / Cruise Control / DTC.

    6. Read the DTCs.

      Result
      Result Proceed to
      DTC is not output A
      DTC P1578 is output B

    B

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER Click here

    A

    USE SIMULATION METHOD TO CHECK Click here

  3. REPLACE BRAKE BOOSTER WITH MASTER CYLINDER

    Replace the brake booster with master cylinder (skid control ECU) Click here for LHD, Click here for RHD).


    NEXT

  4. CHECK WHETHER DTC OUTPUT RECORDS (CRUISE CONTROL SYSTEM)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the intelligent tester on.

    4. Clear the DTC Click here.

    5. Perform the following to make sure that the DTC detection conditions are met.

      Tech Tips

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


      1. Drive the vehicle at a speed of 40 km/h (25 mph) or more.

      2. Turn the cruise control switch (ON-OFF button) on.

      3. Push the -SET button to activate the cruise control.

    6. Enter the following menus: Powertrain / Cruise Control / DTC.

    7. Read the DTCs.

      Result
      Result Proceed to
      DTC is not output A
      DTC P1578 is output B

    B

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

    A

    END