5. Both Wipers and Washer Do Not Work
CIRCUIT OPERATION
Battery voltage is always applied to the FRONT-ECU, ETACS-ECU, and column switch (COLUMN-ECU).When the wiper/washer switch is operated with the ignition switch at "ACC" position, a signal is sent to the FRONT-ECU. The signal turns on and off the relay, which is incorporated in the FRONT-ECU, causing current to flow to the wiper motor or washer motor.
TECHNICAL DESCRIPTION (COMMENT)
The cause may be a malfunction of the windshield wiper and washer power supply circuit, ETACS-ECU, FRONT-ECU, column switch, SWS communication line or ground circuit.
TROUBLESHOOTING HINTS
The most likely causes for this case:
- Malfunction of the column switch
- Damaged wiring harness and connector
- Malfunction of the ETACS-ECU
- Malfunction of the FRONT-ECU
DIAGNOSIS
Required Special Tools:
MB991502: Scan Tool (MUT-II)
MB991529: Diagnostic Trouble Code Check Harness
MB991223: Harness Set
CAUTION: To prevent damage to scan tool MB991502, make sure that the ignition switch is "OFF" before connecting or disconnecting the scan tool.
STEP 1. Check the ETACS-ECU input signal using either the scan tool or the voltmeter.
- Using scan tool MB991502
1. Connect scan tool MB991502 to the data link connector.
2. If the tone alarm of scan tool MB991502 sounds once when the windshield wiper and washer switch is operated, the ETACS-ECU input signal for that switch circuits are normal.
- Using a voltmeter
1. Use special tool MB991529 to connect a voltmeter between ground terminal (4) or (5) and the ETACS-ECU terminal of the data link connector
2. If a voltmeter indicator deflects once when the windshield wiper and washer switch is operated, the ETACS-ECU input signal for that switch circuit system is normal.
If the input signal of the ignition switch (ACC) is not normal, go to Step 2.
If the input signal of the column switch (wiper and washer) is not normal, go to Step 3.
If the input signals of the ignition switch (ACC) and column switch (wiper and washer) are normal, go to Step 13.
STEP 2. Check the ignition switch (ACC) power supply line at ETACS-ECU connector C-86.
1. Remove the ETACS-ECU
2. Connect connector C-73 to the junction block and measure at the junction block side.
3. Measure the voltage between terminal (7) and ground when the ignition is at the "ACC" position.
- Voltage should be approximately 12 volts (battery positive voltage).
If not approximately 12 volts, go to Step 4. If approximately 12 volts, go to Step 6.
STEP 3. Check the power supply line at column switch connector C-60.
1. Remove the column cover and measure at the harness side.
2. Measure the voltage between terminal (1) and ground.
- Voltage should be approximately 12 volts (battery positive voltage)
If not approximately 12 volts, go to Step 5. If approximately 12 volts, go to Step 7.
STEP 4. Check the harness wire between the ignition switch (ACC) and ETACS-ECU connector C-86.
1. Remove the column cover.
2. Check the harness wire between ignition switch (ACC) and ETACS-ECU connector C-86.
If any harness wire between the ignition switch (ACC) and ETACS-ECU connector C-86 is damaged, repair it. Then go to Step 17.
NOTE: After checking intermediate connector C-73, check the wire. If intermediate connector C-73 is damaged, repair or replace it. Refer to Harness Connector Inspection.
Then go to Step 17
STEP 5. Check the harness wire between the battery and column switch connector C-60.
If any harness wire between the battery and column switch connector, repair it. Then go to Step 17.
STEP 6. Check the harness wire between ETACS-ECU connector C-86 and ground.
If any harness wire between ETACS-ECU connector C-86 and ground is damaged, repair it. Then go to Step 9.
If any harness wire between ETACS-ECU connector C-86
and ground is not damaged, replace the ETACS-ECU. Then
go to Step 17.
NOTE: After checking intermediate connectors C-66 and C-73, check the wire. If intermediate connectors C-66 and C-73 are damaged, repair or replace then. Refer to Harness Connector Inspection.
Then go to Step 17
STEP 7. Check the harness wire between column switch connector C-60 and ETACS-ECU connector C-82.
1. Remove the instrument side cover (LH) .
2. Check the harness wire between column switch connector C-60 and ETACS-ECU connector C-82.
If any harness wire between column switch connector C-60 and ETACS-ECU connector C-82 is damaged, repair it.
Then go to Step 8.
STEP 8. Check the harness wire between column switch connector C-60 and ground.
If any harness wire between column switch connector C-60 and ground is damaged, repair it. Then go to Step 9.
If any harness wire between column switch connector C-60 and ground is not damaged, replace the column switch. Then go to Step 17.
NOTE: After checking intermediate connectors C-73 and C-84, check the wire. If intermediate connectors C-73 and C-84 are damaged, repair or replace them. Refer to Harness Connector Inspection.
Then go to Step 17.
STEP 9. Check the power supply line at FRONT-ECU connector A-09X.
1. Remove the FRONT-ECU and measure at the harness side.
2. Measure the voltage between terminal (6) and ground.
- Voltage should be approximately 12 volts (battery positive voltage).
If not approximately 12 volts, go to Step 10. If approximately 12 volts, go to Step 12.
STEP 10. Check the harness wire between the battery and FRONT-ECU connector A-09X.
If any harness wire between the battery and FRONT-ECU connector A-09X is damaged, repair it. Then go to Step 17.
If any harness wire between the battery and FRONT-ECU connector A-09X is not damaged, go to Step 11.
STEP 11. Check the harness wire between FRONT-ECU connector A-09X and ground.
If any harness wire between FRONT-ECU connector A-09X and ground is damaged, repair it. Then go to Step 17.
CAUTION: To prevent damage to scan tool MB991502, make sure that the ignition switch is "OFF" before connecting or disconnecting the scan tool.
STEP 12. Check the diagnostic trouble code.
Connect scan tool MB991502 to the data link connector, and then check the diagnostic trouble code.
If code number 11 is displayed on scan tool MB991502, replace the ETACS-ECU. Then go to Step 17.
If code number 12 is displayed on scan tool MB991502, go to Step 13
If code number 13 is displayed on scan tool MB991502, go to Step 17.
If code number 21 is displayed on scan tool MB991502, go to Step 13.
STEP 13. Check the harness wire between FRONT-ECU connector A-09X and ETACS-ECU connector C-82.
1. Remove the FRONT-ECU.
2. Remove the instrument side cover (LH).
3. Check the harness wire between FRONT-ECU connector A-09X and ETACS-ECU connector C-82.
If any harness wire between FRONT-ECU connector A-09X and ETACS-ECU connector C-82 is damaged, repair it.
Then go to Step 17.
If any harness wire between FRONT-ECU connector A-09X and ETACS-ECU connector C-82 is not damaged, go to Step 14.
STEP 14. Check the ignition switch (ACC) power supply line at the FRONT-ECU connector A-09X. Measure the voltage between terminal (7) and ground when the ignition is at "ACC" position.
- Voltage should be approximately 12 volts (battery positive voltage).
If not approximately 12 volts, go to Step 16. If approximately 12 volts, go to Step 17.
STEP 15. Check the harness wire between FRONT-ECU connector A-09X and intermediate connector C-73. If any harness wire between FRONT-ECU connector A-09X and intermediate connector C-73 is damaged, repair it. Then go to Step 17.
NOTE: After checking intermediate connectors C-66 and C-87, check the wire. If intermediate connectors C-66 and C-87 are damaged, repair or replace them. Refer to Harness Connector Inspection. Then go to Step 17
STEP 16. Check intermediate connector C-05.
If intermediate connector C-05 is damaged, repair or replace it.
Refer to Harness Connector Inspection. Then go to Step 17.
STEP 17. Check symptoms.
Confirm that the harness wire, intermediate connector, windshield washer motor, FRONT-ECU and column switch are normal.