Vehicle Stability Control System (For BOSCH Made)

BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM (for BOSCH Made): C0278/11: Open or Short Circuit in ABS Solenoid Relay Circuit
C0278/11 - Open or Short Circuit in ABS Solenoid Relay Circuit

DESCRIPTION

The ABS solenoid relay supplies power to the ABS solenoid.

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

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

HINT
If a speed signal of 4 mph (6 km/h) or more is input to the skid control ECU, with the ignition switch on (IG) and the stop light switch off, the skid control ECU performs self diagnosis of the motor and solenoid circuits.





WIRING DIAGRAM





INSPECTION PROCEDURE

HINT
* When C1241/41 is output together with C0278/11, inspect and repair the trouble areas indicated by C1241/41 C1241.
* Check the condition of each related circuit connector before troubleshooting Electronic Circuit Inspection Procedure.

PROCEDURE

1. INSPECT FUSIBLE LINK (ABS NO. 2 FUSE)

(a) Remove the fusible link from the engine room R/B.





(b) Check if the fusible link is melted.

OK:

The fusible link is not melted.

(c) Install the fusible link to the engine room R/B with the nut.

Torque : 5.4 Nm (55 kgf-cm, 48 in-lbf)

NG -- REPLACE FUSIBLE LINK
OK -- Continue to next step.

2. INSPECT SKID CONTROL ECU (+BS TERMINAL VOLTAGE)

(a) Disconnect the skid control ECU connector.





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

Standard voltage:





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

3. INSPECT SKID CONTROL ECU (GND TERMINAL CONTINUITY)

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





Standard resistance:





(b) Connect the connector.

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

4. RECONFIRM DTC

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

The solenoid circuit is located in the brake actuator assembly.

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

(a) Clear the DTC Vehicle Stability Control System (for BOSCH Made).

(b) Start the engine.

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

(d) Check if the same DTC is recorded Vehicle Stability Control System (for BOSCH Made).

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

Result:





HINT
* 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 (skid control ECU), inspect and repair the connector or wire harness.
* It is suspected that the DTCs were output due to a bad connection of the connector terminal.

B -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal

A -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) Diagnosis System