VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C0278, C0279

DESCRIPTION

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

On vehicles equipped with the Stop and Start System, DTC may be output if there is a significant difference between IG power source voltage and backup boost converter power source voltage when the stop and start system is cranking the engine during restarting.

WIRING DIAGRAM

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

INSPECTION PROCEDURE

PROCEDURE

1. INSPECT SKID CONTROL ECU (+BS TERMINAL)

   
   

   1. Turn the ignition switch off.

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

   3. Check the connector case and terminals for deformation and corrosion.

      Standard condition
      No deformation or corrosion.

   4. 

      Text in Illustration

      *A	for LHD
      *B	for RHD
      *1	Front view of wire harness connector (to Skid Control ECU)

      Disconnect the A16 or A17 skid control ECU connector.

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

      Standard Voltage
      for LHD Tester Connection Condition Specified Condition A16-12 (+BS) - Body ground Always 11 to 14 V
      for RHD Tester Connection Condition Specified Condition A17-12 (+BS) - Body ground Always 11 to 14 V

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR (+BS CIRCUIT)

   OK

2. INSPECT SKID CONTROL ECU (GND TERMINAL)

   
   
   1. 

      Text in Illustration

      *A	for LHD
      *B	for RHD
      *1	Front view of wire harness connector (to Skid Control ECU)

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

      Standard Resistance
      for LHD Tester Connection Condition Specified Condition A16-1 (GND1) - Body ground Always Below 1 Ω
      for RHD Tester Connection Condition Specified Condition A17-1 (GND1) - Body ground Always Below 1 Ω

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)

   OK

3. RECONFIRM DTC

   Tech Tips

   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.

   
   

   1. Reconnect the skid control ECU connector.

   2. Clear the DTC Click here.

   3. Start the engine.

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

   5. Check if the same DTC is recorded Click here.

      Result

      Result	Proceed to
      DTC not output	A
      DTC output	B

      Tech Tips

      
      

      • 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 Click here

   A

   CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) Click here