ELECTRONICALLY CONTROLLED BRAKE SYSTEM, Diagnostic DTC:C1202/68

DTC Code DTC Name
C1202/68 Master Reservoir Level Malfunction

DESCRIPTION

When a fluid level drop in the master cylinder reservoir is detected, the signal is input to the skid control ECU assembly.

If the DTC for the fluid level drop is memorized, the warning will be canceled and the DTC will not be stored when the fluid level returns to normal.

DTC Code INF Code DTC Detection Condition Trouble Area
C1202/68 511 When the brake fluid level has dropped to the warning level, it is determined that each cylinder reservoir is empty or will soon become empty.

  • Brake fluid leak

  • Brake fluid level

  • Brake fluid level warning switch (Brake master cylinder reservoir assembly)

  • Brake fluid level warning switch circuit

  • Skid control ECU assembly
↑ 512 An open in the switch signal circuit continues for 2 seconds or more.

  • Brake fluid level warning switch (Brake master cylinder reservoir assembly)

  • Brake fluid level warning switch circuit

  • Skid control ECU assembly

WIRING DIAGRAM

A01FR5DE08

INSPECTION PROCEDURE

Note

When replacing the skid control ECU assembly, perform initialization and calibration of the linear solenoid valve Click here.

Tech Tips

When releasing the parking brake, chock the wheels for safety.

PROCEDURE


  1. CHECK BRAKE FLUID LEVEL


    1. Check that the brake fluid level is sufficient.

      OK
      Brake fluid level is sufficient.

      Tech Tips


      • If the fluid level drops, check for fluid leaks, and repair as necessary.

      • Check for brake fluid leakage (connection between the brake master cylinder reservoir assembly and brake actuator assembly, and the brake actuator assembly and wheel cylinders).

      • If no leak exists, add and adjust fluid and then check that the trouble code is not output again.


    NG

    CHECK AND REPAIR BRAKE FLUID LEAKAGE OR ADD FLUID

    OK

  2. INSPECT BRAKE FLUID LEVEL WARNING SWITCH


    1. A01FRL5E05
      Text in Illustration
      *a

      Component without harness connected

      (Brake Fluid Level Warning Switch [Brake Master Cylinder Reservoir Assembly])

      Turn the power switch off.

    2. Remove the reservoir filler cap and strainer.

    3. Make sure that there is no looseness at the locking part and the connecting part of the connector.

    4. Disconnect the A28 brake fluid level warning switch (brake master cylinder reservoir assembly) connector.

    5. Measure the resistance according to the value(s) in the table below.

      Tech Tips

      A float is located inside the reservoir. Its position changes according to the level of brake fluid.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      2 (LBL) - 1 (GND) Brake fluid level warning switch OFF (Float up) 1.84 to 2.16 kΩ
      2 (LBL) - 1 (GND) Brake fluid level warning switch ON (Float down) Below 1 Ω

      Tech Tips

      If there are no problems after completing the preceding inspection, adjust the brake fluid to the MAX level with the power switch on (IG).


    NG

    REPLACE BRAKE MASTER CYLINDER RESERVOIR ASSEMBLY Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU ASSEMBLY - BRAKE FLUID LEVEL WARNING SWITCH)


    1. Make sure that there is no looseness at the locking part and the connecting part of the connector.

    2. Disconnect the A14 skid control ECU assembly connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      A14-45 (LBL) - A28-2 (LBL) Always Below 1 Ω
      A14-45 (LBL) - Body ground Always 10 kΩ or higher
      A28-1 (GND) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. INSPECT SKID CONTROL ECU ASSEMBLY (SWITCH INPUT)


    1. A01FS5WE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Brake Fluid Level Warning Switch [Brake Master Cylinder Reservoir Assembly])

      Reconnect the skid control ECU assembly connector.

    2. Turn the power switch on (IG).

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A28-2 (LBL) - Body ground Power switch on (IG) 4 to 8 V

    NG

    REPLACE SKID CONTROL ECU ASSEMBLY Click here

    OK

  5. RECONFIRM DTC


    1. Reconnect the brake fluid level warning switch (brake master cylinder reservoir assembly) connector.

    2. Turn the power switch off.

    3. Clear the DTCs Click here.

    4. Turn the power switch on (IG).

    5. Check if the same DTC is recorded Click here.

      Result
      Result Proceed to
      DTC (C1202/68) is not output A
      DTC (C1202/68) is output B

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step Click here.


    B

    REPLACE SKID CONTROL ECU ASSEMBLY Click here

    A

    CHECK FOR INTERMITTENT PROBLEMS Click here