Up to 08/2009

BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM: C1377/43: Capacitor Malfunction
C1377/43 - Capacitor Malfunction

DESCRIPTION

The brake control power supply (capacitor) is used as auxiliary power for brake control when the auxiliary battery voltage is low.





WIRING DIAGRAM





INSPECTION PROCEDURE

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

PROCEDURE

1. CHECK FREEZE FRAME DATA

(a) Check the INF code from the Freeze Frame Data memorized when the DTC (C1377/43) is stored Freeze Frame Data.

Result:





C -- CHECK AUXILIARY BATTERY

B -- REPLACE BRAKE CONTROL POWER SUPPLY
A -- Continue to next step.

2. INSPECT CAPACITOR FUSE

(a) Remove the CAPACITOR fuse from the fuse box.





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

Standard Resistance:





Text in Illustration





NG -- REPLACE CAPACITOR FUSE
OK -- Continue to next step.

3. INSPECT BRAKE CONTROL POWER SUPPLY (+BC TERMINAL)

(a) Install the CAPACITOR fuse.





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

(c) Disconnect the brake control power supply connector.

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

Standard Voltage:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (+BC CIRCUIT)
OK -- Continue to next step.

4. INSPECT BRAKE CONTROL POWER SUPPLY (GND TERMINAL)

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





Standard Resistance:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)
OK -- Continue to next step.

5. INSPECT BRAKE CONTROL POWER SUPPLY (CAPACITOR POWER SUPPLY OUTPUT)

(a) Reconnect the brake control power supply connector.





(b) Turn the power switch on (IG).

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

Standard Voltage:





Text in Illustration





NG -- REPLACE BRAKE CONTROL POWER SUPPLY
OK -- Continue to next step.

6. INSPECT SKID CONTROL ECU (CAPACITOR POWER SUPPLY INPUT)

(a) Reconnect the skid control ECU connectors.





(b) Turn the power switch on (IG).

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

Standard Voltage:





Text in Illustration





NG -- REPLACE SKID CONTROL ECU Removal
OK -- Continue to next step.

7. RECONFIRM DTC

(a) Turn the power switch off.

(b) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.

(c) Turn the power switch on (IG).

(d) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.

Result:





B -- REPLACE SKID CONTROL ECU Removal

A -- CHECK FOR INTERMITTENT PROBLEMS How To Proceed With Troubleshooting

8. CHECK AUXILIARY BATTERY

(a) Check the auxiliary battery voltage.

Standard Voltage:

11 to 14 V

NG -- CHARGE OR REPLACE AUXILIARY BATTERY
OK -- Continue to next step.

9. INSPECT BRAKE CONTROL POWER SUPPLY (+BC TERMINAL)

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





(b) Disconnect the brake control power supply connector.

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

Standard Voltage:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (+BC CIRCUIT)
OK -- Continue to next step.

10. INSPECT BRAKE CONTROL POWER SUPPLY (GND TERMINAL)

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





Standard Resistance:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)

OK -- REPLACE BRAKE CONTROL POWER SUPPLY