DTC    C1391/69    Accumulator Leak Malfunction

for Preparation Click here


DESCRIPTION

The DTC is stored if a brake fluid or internal or other leak is detected due to improper sealing in the actuator. Internal leakage is suspected if the pump motor operates frequently without braking.

DTC No.
INF Code
DTC Detection Condition
Trouble Area
C1391/69
591
When either of the following is detected:
  1. Before braking and when the pump motor is running, the accumulator pressure sensor input does not rise.
  2. Before braking and when the pump motor is not running, the falling rate of the accumulator pressure sensor input continues to be greater than the standard value.
  1. Fluid leakage
  2. Brake actuator assembly

INSPECTION PROCEDURE

NOTICE:
When replacing the skid control ECU or brake actuator assembly, perform initialization of linear solenoid valve and calibration (Click here).

1.CHECK BRAKE FLUID LEAKAGE

  1. Check that there is no fluid leakage in the brake line between the brake actuator and the wheel cylinder which is the cause of DTCs.

  1. Check that the brake is not dragging.

    OK:
    There is no fluid leakage or dragging.



NG
REPAIR OR REPLACE APPLICABLE PART
OK


2.READ VALUE OF INTELLIGENT TESTER (ACCUMULATOR PRESSURE SENSOR)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the engine switch on (IG).

  1. Select the DATA LIST mode on the intelligent tester.

    ABS / VSC / TR(A)C: 
    Item (Display)
    		Measurement Item /
    Range (Display)
    		Normal Condition
    Accumulator Sensor
    		Accumulator pressure sensor 1 / min.: 0 V, max.: 5 V
    		Specified value: 3.2 to 4.0 V

  1. Wait a few minutes without operating the brake pedal.

  1. Check that the output value of the accumulator pressure sensor does not decrease and that the pump motor is not activated due to a decrease in accumulator pressure.

    OK:
    Accumulator pressure does not decrease and the pump motor is not activated due to a decrease in accumulator pressure.



NG
REPLACE BRAKE ACTUATOR ASSEMBLY
OK


3.RECONFIRM DTC

  1. Clear the DTC (Click here).

  1. Turn the engine switch on (IG).

  1. Check if the same DTC is recorded (Click here).

    Result:

    Condition
    		Proceed To
    DTC (C1391/69) is not output
    		A
    DTC (C1391/69) is output
    		B



B
REPLACE SKID CONTROL ECU
A

END