C0279

BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: C0278, C0279: Open in ABS Solenoid Relay Circuit
C0279 - Short in ABS Solenoid Relay Circuit

DESCRIPTION

The ABS solenoid relay supplies power to the ABS solenoid and TRAC solenoid.

The solenoid relay is turned on 1.5 seconds after the ignition switch is turned to ON, and is turned off if an open or short in the solenoid is detected by the self diagnosis performed when the engine starts running.

The ABS solenoid relay is housed in the skid control ECU in the actuator assembly.





WIRING DIAGRAM

Refer to DTCs C0226, C0236, C0246, C0256 and C1225 C0226.

INSPECTION PROCEDURE

NOTICE:
* When replacing the brake actuator assembly, perform zero point calibration Programming and Relearning.
* Inspect the fuses for circuits related to this system before performing the following inspection procedure.

HINT
When C1241 is output together with C0278 and/or C0279, inspect and repair the trouble areas indicated by C1241 first C1241.

PROCEDURE

1. INSPECT SKID CONTROL ECU (+BS TERMINAL)

(a) Turn the ignition switch off.

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

(c) Check the connector case and terminals for deformation and corrosion.

Standard condition:

No deformation or corrosion.

(d) Disconnect the A16 skid control ECU connector.





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

Standard Voltage:





Text in Illustration





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

2. INSPECT SKID CONTROL ECU (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.

3. RECONFIRM DTC

HINT
This code is detected when a problem is identified in the brake actuator assembly.

The solenoid circuit is in the brake actuator assembly.

Therefore, solenoid circuit inspection and solenoid unit inspection cannot be performed. Be sure to check if the DTC is output before replacing the brake actuator assembly.

(a) Reconnect the skid control ECU connector.

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

(c) Start the engine.

(d) Drive the vehicle at a speed of 20 km/h (12 mph) or more for 30 seconds or more.

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

Result





HINT
* If a speed signal of 6 km/h (4 mph) or more is input to the skid control ECU, with the ignition switch ON and the stop light switch off, the ECU performs self diagnosis of the motor and solenoid circuits.
* If the normal system code is output (the trouble code is not output), slightly jiggle the connectors, wire harnesses, and fuses of the brake actuator assembly. Make sure that no DTCs are output.
* If any DTCs are output while jiggling a connector or wire harness of the brake actuator assembly (skid control ECU), inspect and repair the connector or wire harness.
* The DTCs were probably output due to a bad connection of the connector terminal.

B -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal

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