Vehicle Stability Control System

VEHICLE STABILITY CONTROL SYSTEM: C0273/13: Open in ABS Motor Relay Circuit

DTC C0273/13 - Open in ABS Motor Relay Circuit

DTC C0274/14 - Short to B+ in ABS Motor Relay Circuit

DTC C1361/91 - Short Circuit in ABS Motor Fail Safe Relay Circuit

DESCRIPTION

If a DTC of the motor line is stored, the ABS CUT (fail safe) relay cuts off the power supply to the ABS MTR relay and performs fail safe.
While any of the ABS, TRAC, VSC, or BA is operating, the skid control ECU (housed in the actuator assembly) turns the ABS MTR relay on and activates the pump motor in the brake actuator.
This code may be stored if the motor relay (BM) voltage becomes lower than the DTC detecting condition due to insufficient output from the battery or alternator.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTE: When replacing the brake actuator assembly, perform zero point calibration (Programming and Relearning).

PROCEDURE

1. INSPECT ABS NO. 1 FUSE





(a) Remove the ABS NO. 1 fuse from the engine room junction block.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:





NG -- REPLACE ABS NO. 1 FUSE
OK -- Continue to next step.
2. INSPECT ABS MOTOR RELAY (ABS MTR RELAY)





(a) Install the ABS NO. 1 fuse.
(b) Remove the ABS MTR relay.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:





NG -- REPLACE ABS MOTOR RELAY (ABS MTR RELAY)
OK -- Continue to next step.
3. INSPECT ABS MOTOR RELAY (ABS CUT (FAIL SAFE) RELAY)





(a) Remove the ABS CUT (fail safe) relay.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:





NG -- REPLACE ABS MOTOR RELAY (ABS CUT (FAIL SAFE) RELAY)
OK -- Continue to next step.
4. INSPECT VSC 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.
5. INSPECT VSC RELAY BLOCK





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





NG -- REPAIR OR REPLACE VSC RELAY BLOCK
OK -- Continue to next step.
6. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - VSC RELAY BLOCK)





(a) Disconnect the skid control ECU connector.
(b) 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.
7. RECONFIRM DTC
(a) Clear the DTC (Vehicle Stability Control System).
(b) Start the engine.
(c) Drive the vehicle at the speed of 6 km/h (4 mph) or more.
(d) Check if the same DTC is recorded (Vehicle Stability Control System).

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

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 harness, 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.

B -- REPLACE BRAKE ACTUATOR ASSEMBLY
A -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION)