Inspection Procedure G-2: The windshield wipers does not work when the wiper switch is at "INT", "WASHER" or "MIST" position. However, the wipers work at low speed when the switch is at "LO" and "HI" position.


caution Whenever the ECU is replaced, ensure that the input and output signal circuits are normal.


COMMENTS ON TROUBLE SYMPTOM
The system may be at fail-safe mode as the SWS communication line is defective. If the front-ECU does not receive the ignition switch (ACC) signal due to an open circuit in the SWS communication lines or other reasons when the ignition switch is at the ACC position, the system will enter the fail-safe mode.

POSSIBLE CAUSES

  • Malfunction of the column switch
  • Malfunction of the front-ECU
  • Damaged harness wires and connectors

DIAGNOSTIC PROCEDURE

Step 1. Check the diagnosis code.
When the ignition switch is turned to the LOCK (OFF) position, check that the ETACS-ECU does not set the diagnosis code.

Q. Is the diagnosis code set?
Refer to diagnosis code chart .
Go to Step 2.

Step 2. Pulse check.
Check the input signals below which are related to the windshield wiper.
System switch
 Check condition
Ignition switch (ACC)
 When turned from the LOCK (OFF) position to the ACC position.
Windshield mist wiper switch
 When the switch is turned from off to on.
OK: The M.U.T.-III sounds or the voltmeter needle fluctuates.

Q. Are the check result normal?
All the signals are received normally : Go to Step 3.
The ignition switch (ACC) signal is not received. : Refer to Inspection Procedure P-1 "The ignition switch (ACC) signal is not received ."
Windshield mist wiper switch signal is not received. : Refer to Inspection Procedure P-6 "The column switch (windshield wiper washer and rear wiper washer switch) signal is not received ."

Step 3. Retest the system.
The windshield wiper should now work normally.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
Replace the front-ECU.