INSPECTION PROCEDURE 1: Rear wiper does not work at all.



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

OPERATION


The ETACS-ECU operates the rear wiper in accordance with the input signals below.

  • Ignition switch (ACC)
  • Rear wiper switch

COMMENTS ON TROUBLE SYMPTOM


If the rear wiper does not work normally, the input signal circuits from the ignition switch (ACC), the column switch (column-ECU), the rear wiper motor or ETACS-ECU may be defective.

PROBABLE CAUSES



  • Defective rear wiper motor
  • Defective column switch (column-ECU)
  • Malfunction of ETACS-ECU
  • Malfunctions of the wiring harness and connectors

DIAGNOSTIC PROCEDURE


STEP 1. M.U.T.-III diagnosis code


Check if an ETACS-related diagnosis code is set.

Q. Is the diagnosis code set?

Troubleshoot the ETACS. Refer to .
Go to Step 2.

STEP 2. M.U.T.-III data list


Check the input signal related to the rear wiper operation.

  • Turn the ignition switch to the ACC position.
Item No.
Item name
Normal conditions
Item 288
ACC switch
ON
OK: Normal condition is displayed.

Q. Is the check result normal?

Go to Step 3.
Refer to GROUP 54A - ETACS, Inspection Procedure 1 "The ignition switch (ACC) signal is not received ."

STEP 3. Check the rear wiper motor.


Refer to GROUP 51 - Rear Wiper and Washer .

Q. Is the rear wiper motor normal?

Go to Step 4.
Replace the rear wiper motor.

STEP 4. Measure the resistance at rear wiper motor connector.


(1)Disconnect the connector, and measure the resistance at the wiring harness.
(2)Measure the resistance between rear wiper motor connector (earth terminal) and body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?

Go to Step 6.
Go to Step 5.

STEP 5. Check of open circuit in earth line between rear wiper motor connector and body earth.


Q. Is the check result normal?


    Go to Step 6.
Repair the wiring harness.

STEP 6. Check of short to the power supply, short to earth and open circuit in RWLO line between rear wiper motor connector and ETACS-ECU connector.


Q. Is the check result normal?

Go to Step 7.
Repair the wiring harness.

STEP 7. Retest the system.


Check that the rear wiper works normally.

Q. Is the check result normal?

Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
Replace the ETACS-ECU.