C0278

BRAKE CONTROL: ANTI-LOCK BRAKE SYSTEM: C0278/11: Open or Short Circuit in ABS Solenoid Relay Circuit

DTC C0278/11 - Open or Short Circuit in ABS Solenoid Relay Circuit

DTC C0279/12 - Short to B+ in ABS Solenoid Relay Circuit

DESCRIPTION

This relay supplies power to each ABS solenoid.
Immediately after the ignition switch is turned to the ON position, the relay turns on if the solenoid is determined to be normal as a result of self-diagnosis during initial check.
The relay turns off if an open / short is detected.
If the voltage supplied to the motor relay (+BS) is below the DTC detection threshold due to battery / generator shortage, the DTCs may be stored.






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. INSPECT FUSE (ABS NO. 2)





(a) Remove the ABS No. 2 fuse from the engine room relay block.
(b) Measure the resistance of the fuse.
Standard resistance:
Below 1 Ohms
NG -- REPLACE FUSE
OK -- Continue to next step.
2. CHECK SKID CONTROL ECU CONNECTOR (+BS VOLTAGE)





(a) Disconnect the S1 skid control ECU connector.
(b) Measure the voltage of the wire harness side connector.
Standard voltage:






NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.
3. CHECK SKID CONTROL ECU CONNECTOR (GROUND)





(a) Disconnect the S1 skid control ECU connector.
(b) Measure the resistance of the wire harness side connector.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.
4. RECONFIRM DTC
(a) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(b) Drive the vehicle at a speed of 6 km/h (4 mph) or more.
(c) Are the same DTCs recorded Reading and Clearing Diagnostic Trouble Codes?
HINT:
- The skid control ECU inspects the solenoid relay circuit when the stop light switch is turned off and the vehicle is running at a speed of 6 km/h (4 mph) or more.
- These DTCs may be recorded due to a malfunction in the connector terminal connection, etc.

NO -- END
YES -- REPLACE BRAKE ACTUATOR ASSEMBLY