C1378

BRAKE CONTROL: ELECTRONICALLY CONTROLLED BRAKE SYSTEM: C1378/44: Capacitor Communication Malfunction

DTC C1378/44 - Capacitor Communication Malfunction

DESCRIPTION

The brake control power supply assembly (capacitor) provides auxiliary power for brake control when an auxiliary battery (12 V) voltage drops.
The FAIL and ENA lines are placed between the skid control ECU and the brake control power supply assembly.
Signals indicating that the brake control power supply is in auxiliary mode are sent to the skid control ECU through the FAIL line.
Charge permit prohibition signals are sent to the brake control power supply through the ENA line.






WIRING DIAGRAM





INSPECTION PROCEDURE
NOTE: When replacing the skid control ECU, perform initialization of linear solenoid valve and calibration Initialization.

PROCEDURE

1. INSPECT BRAKE CONTROL POWER SUPPLY (IG1 TERMINAL)





(a) Measure the voltage according to the value(s) in the table below.
HINT: Measure the voltage from the back side of the connector with the connector connected to the skid control ECU.

Voltage:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (BETWEEN SKID CONTROL ECU AND BRAKE CONTROL POWER SUPPLY)





(a) Turn the ignition switch off.
(b) Disconnect the skid control ECU connector and brake control power supply connector.
(c) Measure the resistance according to the value(s) in the table below.
Resistance:





(d) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
3. CHECK FREEZE FRAME DATA
(a) Check the INF code from the Freeze Frame Data memorized when the DTC (C1378/44) is stored Freeze Frame Data.
Result:






B -- REPLACE BRAKE CONTROL POWER SUPPLY
A -- REPLACE SKID CONTROL ECU