Inspection Procedure G-1: The windshield wipers does not work at all.


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


COMMENTS ON TROUBLE SYMPTOM
The windshield wiper motor, the column switch or the front-ECU may be defective.

POSSIBLE CAUSES

  • Malfunction of the windshield wiper motor
  • 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. Connector check: A-01 windshield wiper motor connector.

Q. Is the check result normal?

Go to Step 4.

Repair the connector.

Step 4. Check the windshield wiper motor assembly.
Refer to GROUP 51 - Windshield wiper .

Q. Is the check result normal?
Go to Step 5.
Replace the windshield wiper motor assembly.

Step 5. Resistance measurement at the A-01 windshield wiper motor connector.

(1)Disconnect the connector, and measure at the wiring harness side.

(2)Continuity between A-01 windshield wiper motor connector terminal No.2, and body earth
OK: 2Ω or less

Q. Is the check result normal?

Go to Step 8.

Go to Step 6.

Step 6. Connector check: A-40 earth connector.

Q. Is the check result normal?

Go to Step 7.

Repair the connector.

Step 7. Check the wiring harness between A-01 windshield wiper motor connector terminal No.2 to A-40 earth connector terminal No.5.


  • Check the earth wires for open circuit.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).

Repair the wiring harness.

Step 8. Connector check: A-15X front-ECU connector.

Q. Is the check result normal?

Go to Step 9.

Repair the connector.

Step 9. Voltage measurement at the A-15X front-ECU connector.

(1)Remove the front-ECU, and measure at the relay box side.
(2)Ignition switch: ACC

(3)Check the voltage between the A-15X front-ECU connector terminal No.24 and body earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 11.

Go to Step 10.

Step 10. Check the wiring harness between A-15X front-ECU connector terminal No.24 to the ignition switch (ACC).



note Prior to the wiring harness inspection, check the junction block connectors C-202, C-203 and intermediate connector C-125 and repair if necessary.

  • Check the power supply line to the ignition switch (ACC) for open circuit.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).

Repair the wiring harness.

Step 11. Retest the system.
The windshield wiper should now work normally at all.

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.