Open in ABS Solenoid Relay Circuit - Vehicle Stability Control System

BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: C0278/11,C0279/12: Open in ABS Solenoid Relay Circuit
C0279/12 - Short to B+ in ABS Solenoid Relay Circuit

DESCRIPTION

The ABS solenoid relay supplies power to the ABS solenoid and TR(A)C solenoid.

The solenoid relay is turned on 1.5 seconds after the engine 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.

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





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
When replacing the skid control ECU, perform zero point calibration and store system information Vehicle Stability Control System.

PROCEDURE

1. INSPECT ABS MAIN3 FUSE

(a) Remove the ABS MAIN3 fuse from engine room No. 1 relay block.





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

Standard resistance:





NG -- REPLACE ABS MAIN3 FUSE
OK -- Continue to next step.

2. INSPECT ABS SOLENOID RELAY (ABS MAIN2)

(a) Install the ABS MAIN3 fuse.





(b) Remove the ABS MAIN2 relay.

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

Standard resistance:





NG -- REPLACE ABS SOLENOID RELAY (ABS MAIN2)
OK -- Continue to next step.

3. INSPECT ENGINE ROOM NO. 3 RELAY BLOCK (POWER SOURCE TERMINAL)

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





Standard voltage:





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

4. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ENGINE ROOM NO. 3 RELAY BLOCK)

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





(b) Disconnect the skid control ECU connectors.

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

Standard resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

5. RECONFIRM DTC

(a) Install the ABS MAIN2 relay.

(b) Reconnect the skid control ECU connectors.

(c) Clear the DTCs Vehicle Stability Control System.

(d) Start the engine.

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

(f) Check if the same DTC is recorded Vehicle Stability Control System.

Result:





HINT
* If a speed signal of 6 km/h (4 mph) or more is input to the skid control ECU with the engine switch on (IG) and the stop light switch off, the ECU performs self diagnosis of the motor and solenoid circuits.
* If the normal system code is output (no trouble codes are output), slightly jiggle the connectors, wire harnesses, and fuses of the skid control ECU and/or brake actuator assembly. Make sure that no DTCs are output.
* If any DTCs are output while jiggling a connector or wire harness of the skid control ECU and/or brake actuator assembly, 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 SKID CONTROL ECU Removal

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