DTC    C1378/44    Capacitor Communication Malfunction

for Preparation Click here


DESCRIPTION

Refer to DTC C1377/43 (Click here).

DTC No.
INF Code
DTC Detection Condition
Trouble Area
C1378/44
112
When either of the following is detected:
  1. Open or short in FAIL line.
  2. Malfunction inside the power back up unit.
  1. Wire harness or connector
  2. Brake control power supply
↑
-
When either of the following is detected:
  1. Open or short in ENA line.
  2. Malfunction inside the skid control ECU (circuit for communication with the brake control power supply).
  1. Wire harness or connector
  2. Brake control power supply
  3. Skid control ECU

WIRING DIAGRAM

Refer to DTC C1377/43 (Click here).

INSPECTION PROCEDURE

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

1.INSPECT BRAKE CONTROL POWER SUPPLY


    C106625E06

  1. Disconnect the brake control power supply connector.

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

    Voltage:
    Tester Connection
    		Specified Condition
    V27-5 (IG1) - Body ground
    		10 to 14 V

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

    Resistance:
    Tester Connection
    		Specified Condition
    V27-14 (GND) - Body ground
    		Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 OR GND CIRCUIT)
OK


2.CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU TO BRAKE CONTROL POWER SUPPLY)


    C110907E02

  1. Disconnect the skid control ECU and brake control power supply connector.

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

    Resistance:
    Tester Connection
    		Specified Condition
    A13-8 (ENA) - V27-12 (ENA)
    		Below 1 Ω
    A13-23 (FAIL) - V27-13 (FAIL)
    		Below 1 Ω

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

    Resistance:
    Tester Connection
    		Specified Condition
    A13-8 (ENA) - Body ground
    		10 kΩ or higher
    A13-23 (FAIL) - Body ground
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
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).

    HINT:
    Reinstall the sensor, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.


    Result:

    Condition
    		Proceed To
    DTC (C1378/44) is not output
    		A
    DTC (C1378/44) is output
    		B



B
Go to step 4
A

END 

4.CHECK FREEZE FRAME DATA

  1. Check the INF code from the FREEZE FRAME DATA memorized when the DTC (C1378/44) is stored (Click here).

    Result:

    Condition
    		Proceed To
    INF code is not output
    		A
    INF code (112) is output
    		B



B
REPLACE BRAKE CONTROL POWER SUPPLY
A

REPLACE SKID CONTROL ECU