INSPECTION PROCEDURE 1: The windshield wipers do not work at all.
Windshield Wiper Power Supply Circuit
CIRCUIT OPERATION
TECHNICAL DESCRIPTION (COMMENT)
If the windshield wiper does not work at all, the windshield wiper motor, column switch (windshield wiper and washer switch) or the ETACS-ECU may be defective.
TROUBLESHOOTING HINTS
DIAGNOSIS
Required Special Tools:
STEP 1. Use the scan tool MB991958 to check if an ETACS-related diagnostic trouble code is set.
Connect the scan tool. Refer to GROUP 54A ETACS, "Diagnostic function".
Q: Is the diagnostic trouble code set?
YES : Diagnose the ETACS-ECU.
NO : Go to Step 2.
STEP 2. Check the input signal related to the windshield wiper operation.
OK: Normal condition is displayed.
Q: Is the check result normal? NO : Go to Step 3.
YES : Refer to GROUP 54A − ETACS, Input signal procedures.
STEP 3. Check windshield wiper motor connector A-08 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is windshield wiper motor connector A-08 in good condition?
YES : Go to Step 4.
NO : Repair or replace the damaged component(s). Refer to GROUP 00E, Harness Connector Inspection. Verify that the windshield wiper works normally.
STEP 4. Check the windshield wiper motor.
Then check that the windshield wiper motor operates normally at high and low speeds.
Q: Does the windshield wiper motor operate normally?
YES : Go to Step 5.
NO : Replace the windshield wiper motor. Verify that the windshield wiper works normally.
STEP 5. Check the ground circuit to the windshield wiper motor. Measure the resistance at the windshield wiper motor connector A-08.
Q: Is the measured resistance 2 Ω or less?
YES : Go to Step 7.
NO : Go to Step 6.
STEP 6. Check the wiring harness between windshield wiper motor connector A-08 (terminal 5) and ground.
Q: Is the wiring harness between windshield wiper motor connector A-08 (terminal 5) 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 the windshield wiper works normally.
STEP 7. Check ETACS-ECU connector C-309 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is ETACS-ECU connector C-304 in good condition?
YES : Go to Step 8.
NO : Repair or replace the damaged component(s). Refer to GROUP 00E, Harness Connector Inspection. Verify that the windshield wiper works normally.
STEP 8. Measure the voltage at ETACS-ECU connector C-309.
Q: Is the measured voltage approximately 12 volts (battery positive voltage)?
YES : Go to Step 10.
NO : Go to Step 9.
STEP 9. Check the wiring harness between ETACS-ECU connector C-309 (terminal 1) and the fusible link (34).
Check the power supply line for open circuits.
Q: Is the wiring harness between ETACS-ECU connector C-309 (terminal 1) and the fusible link (34) in good condition?
YES : Intermittent malfunction. Refer to GROUP 00, How to cope with intermittent malfunction.
NO : Repair or replace the damaged component(s).
STEP 10. Check the wiring harness between ETACS-ECU connector C-304 (terminals 5, 6) and windshield wiper motor connector A-08 (terminals 1, 4).
Check the input and output lines for open or short circuit.
Q: Is the wiring harness between ETACS-ECU connector C-304 (terminals 5, 6) and windshield wiper motor connector A-08 (terminals 1, 4) in good condition?
YES : Go to Step 11.
NO : Repair or replace the damaged component(s).
STEP 11. Retest the system.
Check that the windshield wipers work normally.
Q: Is the check result normal?
YES : Intermittent malfunction. NO : Replace the ETACS-ECU.
INSPECTION PROCEDURE 2: The windshield wipers do not work when the wiper switch is at the "INT", "Washer" or "Mist" position. However, the wipers work at low speed when the switch is at the "Lo" or "Hi" position.
Windshield Wiper Motor Circuit
TECHNICAL DESCRIPTION (COMMENT)
This system may be at fail-safe mode if the LIN communication line is defective.
If the system cannot receive any signal from the column switch (windshield wiper and washer switch) due to a open circuit in the LIN communication line or other reasons, the system will enter the fail-safe mode when the ignition switch is at the "ACC" position.
TROUBLESHOOTING HINTS
DIAGNOSIS
Required Special Tools:
STEP 1. Use the scan tool MB991958 to check if an ETACS-related diagnostic trouble code is set.
Connect the scan tool. Refer to GROUP 54A ETACS, "Diagnostic function".
Q: Is the diagnostic trouble code set?
YES : Diagnose the ETACS-ECU.
NO : Go to Step 2.
STEP 2. Retest the system.
Check that the windshield wipers work normally.
Q: Is the check result normal?
YES : Intermittent malfunction. NO : Replace the ETACS-ECU.
INSPECTION PROCEDURE 3: Windshield wipers do not stop at the specified park position.
Windshield Wiper Automatic Stop Relay Circuit
TECHNICAL DESCRIPTION (COMMENT)
If the windshield wipers do not stop at predetermined park position, the windshield wiper motor or the ETACS-ECU may be defective.
TROUBLESHOOTING HINTS
DIAGNOSIS
Required Special Tools:
STEP1. Check windshield wiper motor connector A-08 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is windshield wiper motor connector A-08 in good condition?
YES : Go to Step 2.
NO : Repair or replace the damaged component(s). Refer to GROUP 00E, Harness Connector Inspection. Verify that the windshield wiper works normally.
STEP 2. Check the windshield wiper motor.
Q: Does the windshield wiper motor operate normally?
YES : Go to Step 3.
NO : Replace the windshield wiper motor. The windshield wiper should now stop at the specified park position.
STEP 3. Check the fusible link (34) circuit to the windshield wiper motor. Measure the voltage at windshield wiper motor connector A-08.
Q: Is the measured voltage approximately 12 volts (battery positive voltage)?
YES : Go to Step 5.
NO : Go to Step 4.
STEP 4. Check the wiring harness between windshield wiper motor connector A-08 (terminal 2) and the fusible link (34).
Check the power supply line for open circuits.
Q: Is the wiring harness between windshield wiper motor connector A-08 (terminal 2) and the fusible link (34) in good condition?
YES : Intermittent malfunction.
NO : Repair or replace the damaged component(s).
STEP 5. Check ETACS-ECU connector C-304 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is ETACS-ECU connector C-304 in good condition?
YES : Go to Step 6.
NO : Repair or replace the damaged component(s).
STEP 6. Check the wiring harness between ETACS-ECU connector C-304 (terminals 8, 12) and windshield wiper motor connector A-08 (terminals 3, 2).
Check the output lines for open or short circuits.
Q: Is the wiring harness between ETACS-ECU connector C-304 (terminals 8, 12) and windshield wiper motor connector A-08 (terminals 3, 2) in good condition?
YES : Go to Step 7.
NO : Repair or replace the damaged component(s).
STEP 7. Retest the system.
Check that the windshield wipers stops at the specified park position.
Q: Is the check result normal?
YES : Intermittent malfunction.
NO : Replace the ETACS-ECU.
INSPECTION PROCEDURE 4: Windshield Wipers do not work normally.
Windshield Wiper Motor Drive Circuit
TECHNICAL DESCRIPTION (COMMENT)
If either of the windshield wiper switch positions is defective, the windshield wiper motor, column switch (windshield wiper and washer switch) or the ETACS-ECU may be defective.
TROUBLESHOOTING HINTS
DIAGNOSIS
Required Special Tools:
STEP 1. Use the scan tool MB991958 to check if an ETACS-related diagnostic trouble code is set.
Connect the scan tool. Refer to "How to connect the scan tool (M.U.T.-III)".
Q: Is the diagnostic trouble code set?
YES : Diagnose the ETACS-ECU.
NO : Go to Step 2.
STEP 2. Using scan tool MB991958, check data list.
Check the input signal related to the windshield wiper operation.
OK: Normal condition is displayed.
Q: Is the check result normal?
YES : Go to Step 3.
NO : Troubleshoot the ETACS-ECU. Refer to ETACS, Diagnosis - Inspection Procedure 12 "ETACS-ECU does not receive any signal from the column switch signal".
STEP 3. Check that the windshield wipers work.
Check that the windshield wipers work at high speed and the mist mode.
Q: Is the check result normal?
YES : Go to Step 4.
NO : Go to Step 10.
STEP 4. Check windshield wiper motor connector A-08 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is windshield wiper motor connector A-08 in good condition?
YES : Go to Step 5.
NO : Repair or replace the damaged component(s). Verify that the windshield wiper operates normally when the windshield wiper switch is moved to each position.
STEP 5. Check the windshield wiper motor.
Then check if the windshield wiper motor operates normally at high and low speeds.
Q: Does the windshield wiper motor operate normally?
YES : Go to Step 6.
NO : Replace the windshield wiper motor. Verify that the windshield wiper operates normally when the windshield wiper switch is moved to each position.
STEP 6. Measure the voltage at windshield wiper motor connector A-08
OK: Battery positive voltage
Q: Is the measured voltage approximately 12 volts (battery positive voltage)?
YES : Intermittent malfunction.
NO : Go to Step 7.
STEP 7. Check ETACS-ECU connector C-304 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is ETACS-ECU connector C-304 in good condition?
YES : Go to Step 8.
NO : Repair or replace the damaged component(s). Verify that the windshield wiper operates normally when the windshield wiper switch is moved to each position.
STEP 8. Check the wiring harness between windshield wiper motor connector A-08 (terminals 1) and ETACS-ECU connector C-304 (terminals 5).
Check the output lines for open or short circuit.
Q: Is the wiring harness between windshield wiper motor connector A-08 (terminals 1) and ETACS-ECU connector C-304 (terminals 5) in good condition?
YES : Go to Step 9.
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 windshield wiper operates normally when the windshield wiper switch is moved to each position.
STEP 9. Retest the system.
Check that the windshield wipers work normally by moving the switch to each position.
Q: Is the check result normal?
YES : Intermittent malfunction.
NO : Replace the ETACS-ECU.
STEP 10. Check the A-08 windshield wiper motor connector
Q: Is the check result normal?
YES : Go to Step 11.
NO : Repair the connector concerned.
STEP 11. Check the windshield wiper motor.
Then check if the windshield wiper motor operates normally at high and low speeds.
Q: Does the windshield wiper motor operate normally?
YES : Go to Step 12.
NO : Replace the windshield wiper motor. Verify that the windshield wiper operates normally when the windshield wiper switch is moved to each position.
STEP 12. Measure the voltage at the A-08 windshield wiper motor connector.
OK: Battery positive voltage
Q: Is the check result normal?
YES : Intermittent malfunction.
NO : Go to Step 13.
STEP 13. Check ETACS-ECU connector C-304 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is ETACS-ECU connector C-304 in good condition?
YES : Go to Step 14.
NO : Repair or replace the damaged component(s). Verify that the windshield wiper operates normally when the windshield wiper switch is moved to each position.
STEP 14. Check the wiring harness wires between C-304 ETACS-ECU connector terminal No. 6 and A-08 windshield wiper motor connector terminal No.4.
Check the output lines for open or short circuit.
Q: Is the check result normal?
YES : Go to Step 15.
NO : Repair the wiring harness.
STEP 15. Retest the system.
Check that the windshield wipers work normally by moving the switch to each position.
Q: Is the check result normal?
YES : Intermittent malfunction.
NO : Replace the ETACS-ECU.
INSPECTION PROCEDURE 5: The windshield intermittent wiper interval cannot be adjusted by operating the windshield intermittent wiper volume control switch.
Windshield Intermittent Wiper Control Circuit
TECHNICAL DESCRIPTION (COMMENT)
If the windshield intermittent wiper interval is not changed by operating the windshield intermittent wiper interval adjusting knob or according to the vehicle speed, the column switch or the ETACS-ECU may be defective.
TROUBLESHOOTING HINTS
DIAGNOSIS
Required Special Tools:
STEP 1. Use the scan tool MB991958 to check if an ETACS-related diagnostic trouble code is set.
Connect the scan tool.
Q: Is the diagnostic trouble code set?
YES : Diagnose the ETACS-ECU.
NO : Go to Step 2.
STEP 2. Check the ETACS configuration function.
Use the ETACS configuration function to check that "Front wiper operation" is set to "variable INT" or "vehicle speed dependent".
Q: Is the check result normal?
YES : Go to Step 3.
NO : Use the ETACS configuration function to set "Front wiper operation" to "variable INT" or "vehicle speed dependent".
STEP 3. Using scan tool MB991958, check data list.
Check the input signal related to the windshield wiper operation.
OK: Normal condition is displayed.
Q: Is the check result normal? NO : Go to Step 4.
YES : Replace the column switch.
STEP 4. Retest the system.
Check that the windshield wiper interval changes when the windshield wiper volume control is rotated.
Q: Is the check result normal?
YES : Intermittent malfunction.
NO : Replace the ETACS-ECU.
INSPECTION PROCEDURE 6: The windshield intermittent wiper interval is not changed according to the vehicle speed.
Windshield Intermittent Wiper Control Circuit
TECHNICAL DESCRIPTION (COMMENT)
If the intermittent wiper interval does not depend on the vehicle speed, the input circuit of the vehicle speed signal and the ETACS-ECU may be defective.
Alternatively, the vehicle speed-dependent wiper may be set to "disabled" by using the configuration function.
TROUBLESHOOTING HINTS
DIAGNOSIS
Required Special Tools:
STEP 1. Retest the system.
Check that the windshield intermittent wiper interval can be adjusted by operating the windshield intermittent wiper interval control switch.
Q: Is the check result normal?
YES : Go to Step 2.
NO : Refer to Inspection Procedure 5 "The windshield intermittent wiper interval cannot be adjusted by operating the windshield intermittent wiper interval control switch" .
STEP 2. Check the ETACS configuration function.
Use the ETACS configuration function to check that "Front wiper operation" is set to "Variable INT" or "Speed sensitive".
Q: Is the check result normal?
YES : Go to Step 3.
NO : Use the ETACS configuration function to set "Front wiper operation" to "variable INT" or "Speed sensitive".
STEP 3. Using scan tool MB991958, check data list.
Check the input signal related to the combination meter.
Q: Is the check result normal?
YES : Go to Step 4.
NO <Normal condition is not displayed for item No. 80.> : Troubleshoot the speedometer.
STEP 4. Retest the system.
Check that the intermittent wiper interval depends on the vehicle speed.
Q: Is the check result normal?
YES : Intermittent malfunction.
NO : Replace the ETACS-ECU.