Inspection Procedure 1

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


















CIRCUIT OPERATION

- The rear wiper switch sends a signal through the column-ECU (incorporated in the column switch) to the ETACS-ECU. If the column-ECU sends a rear wiper switch "ON" signal to the ETACS-ECU, the ETACS-ECU turns on the relay (incorporated in the ETACS-ECU), thus causing the rear wiper motor to be turned on.

- The ETACS-ECU operates the rear wiper according to the following switches:
- Ignition switch (ACC)
- Rear wiper switch

TECHNICAL DESCRIPTION (COMMENT)

If the rear wiper does not work normally, the input circuit system from the switches, the rear wiper motor, the column switch (windshield wiper and windshield washer switch) or the ETACS-ECU may be defective.

TROUBLESHOOTING HINTS

- The rear wiper motor may be defective
- The column switch (windshield wiper and washer switch) may be defective
- The ETACS-ECU may be defective
- The wiring harness may be damaged or the connectors may have loose, corroded or damaged terminals, pushed back in the connector

DIAGNOSIS

Required Special Tools:

- MB991223: Harness Set
- MB992006: Extra Fine Probe
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicles communication interface (V.C.I.)
- MB991827: M.U.T.-III USB cable
- MB991911: M.U.T.-III Main harness B

STEP 1. Use the scan tool MB991958 to check if an ETACS-related diagnostic trouble code is set.





Connect the scan tool. Reading and Clearing Diagnostic Trouble Codes."

Q. Is the diagnostic trouble code set?

YES Diagnose the ETACS-ECU. Electronic Time and Alarm Control System (ETACS).

NO Go to Step 2.

STEP 2. Check the input signal related to the rear wiper operation.

- Ignition switch: ACC





OK: Normal condition is displayed.


Q. Is the check result normal?

NO Go to Step 3.
YES Symptom Chart.
STEP 3. Check the rear wiper motor connector F-32 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q. Is rear wiper motor connector F-32 in good condition?

YES Go to Step 4.
NO Repair or replace the damaged component(s). Harness Connector Inspection. Verify that the rear wiper works normally.
STEP 4. Check the rear wiper motor.





(1)Disconnect rear wiper motor connector F-32.
(2)Connect a battery to the wiper motor as shown in the illustration and inspect the motor operation.

Q. Is the rear wiper motor in good condition?

YES Go to Step 5.

NO Replace the rear wiper motor. Verify that the rear wiper works normally.

STEP 5. Check the ground circuit to the rear wiper motor. Measure the resistance at the rear wiper motor connector F-32.

(1)Disconnect rear wiper motor connector F-32 and measure the resistance available at the wiring harness side of the connector.





(2)Measure the resistance value between terminal 3 and ground.

- The resistance should be 2ohms or less.

Q. Is the measured resistance 2ohms or less?

YES Go to Step 7.

NO Go to Step 6.

STEP 6. Check the wiring harness between rear wiper motor connector F-32 (terminal 3) and ground.

Q. Is the wiring harness between rear wiper motor connector F-32 (terminal 3) and ground in good condition?

YES No action is necessary and testing is complete.
NO The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Verify that the rear wiper works normally.
STEP 7. Check ETACS-ECU connector C-311 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q. Is ETACS-ECU connector C-311 in good condition?

YES Go to Step 8.
NO Repair or replace the damaged component(s). Harness Connector Inspection. Verify that the rear wiper works normally.
STEP 8. Check the wiring harness between rear wiper motor connector F-32 (terminal 1) and ETACS-ECU connector C-311 (terminal 5).

NOTE:
Also check junction block connector D-15, F-31 for loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair or replace the damaged component(s) as described in Harness Connector Inspection Harness Connector Inspection.

Q. Is the wiring harness between rear wiper motor connector F-32 (terminal 1) and ETACS-ECU connector C-311 (terminal 5) in good condition?

YES Replace the ETACS-ECU. Verify that the rear wiper works normally.
NO The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Verify that the rear wiper works normally.