If there is any problem in the CAN bus lines, an incorrect DTC may be set. Prior to this diagnosis, diagnose the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ).
Whenever ECU is replaced, ensure that the CAN bus lines are normal.
OPERATION
ASC-ECU contains the power supply circuit (+BV terminal) for the solenoid valve. The solenoid valve is energized by the valve relay, which is incorporated in ASC-ECU.
The valve relay, which is incorporated in ASC-ECU, is always energizing the solenoid valve unless the initial check is in progress when the ignition switch is turned on, and the recurrent system check is in progress.
ASC-ECU activates the solenoid valve by turning on its driving transistor.
DTC SET CONDITIONS
These DTCs will be set under the cases below:
The solenoid valve is not energized even after ASC-ECU has turned on the driving transistor (Open circuit is present in the power supply circuit to the ASC-ECU solenoid valve, or the valve relay has failed).
After ASC-ECU has turned off the driving transistor, the solenoid valve still remains energized (short in the solenoid valve circuit).
When a solenoid valve failure is detected
PROBABLE CAUSES
ASC-ECU malfunction
DIAGNOSIS
Check whether the DTC is set again.
(1) Erase the DTC.
(2) Turn the ignition switch to the "LOCK" (OFF) position.
(3) Turn the ignition switch to the "ON" position.
Is the relevant DTC set?
Replace the hydraulic unit (integrated with ASC-ECU) (Refer to ).
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/How to Cope with Intermittent Malfunctions ).
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Replace the hydraulic unit (integrated with ASC-ECU) (Refer to 
).
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/How to Cope with Intermittent Malfunctions