Inspection Procedure G-2

INSPECTION PROCEDURE G-2: Windshield Wiper and Washer: Any of the windshield wiper switch positions is defective.

WINDSHIELD WIPER MOTOR DRIVE CIRCUIT
- Refer to Inspection Procedure G-1 "Windshield wiper does not operate."

CIRCUIT OPERATION
A signal from the windshield wiper switch is sent through the column-ECU inside the column switch to the front-ECU. The signal turns on the relay inside the front-ECU to operate the wiper motor.

TECHNICAL DESCRIPTION (COMMENT)
The windshield wiper motor, column switch (windshield wiper and washer switch) or the front-ECU may be defective.

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

DIAGNOSIS
Required Special Tools:
- MB991223: Test Harness Set
- MB991502: Scan Tool (MUT-II)
- MB991529: Diagnostic Trouble Code Check Harness

STEP 1. Check method of the input signal

Q: Which is to be used, the scan tool or a voltmeter to check the input signal?

Scan tool MB991502 : Go to Step 2.

Voltmeter : Go to Step 3.

STEP 2. Check the input signal (by using scan tool MB991502).
Check the input signals from the windshield wiper switches.

CAUTION : To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.




1. Connect scan tool MB991502 to the data link connector.
2. Check that the tone alarm of scan tool MB991502 sounds when the input signal enters.

Q: Does the tone alarm of scan tool MB991502 sound when the input signal enters?

YES : Go to Step 4.

NO : Scan tool MB991502 does not sound when the windshield wiper switch is turned from "OFF" to "MIST", "INT", "LO" or "HIGH": Refer to Inspection Procedure O-16 "The windshield mist wiper switch, windshield intermittent wiper switch, windshield low-speed wiper switch, windshield high-speed wiper switch or windshield washer switch signal is not sent to the ETACS-ECU."

STEP 3. Check the input signal (by using a voltmeter).
Check the input signals from the windshield wiper switches.




1. Use special tool MB991529 to connect a voltmeter between ground terminal 4 or 5 and ETACS-ECU terminal 9 of the data link connector.
2. Check that the voltmeter indicator deflects once when the input signal enters.

Q: Does the voltmeter indicator deflect?

YES : Go to Step 4.

NO : The voltmeter needle does not fluctuate when the windshield wiper switch is turned from "OFF" to "MIST", "INT", "LO" or "HIGH": Refer to Inspection Procedure 0-16 "The windshield mist wiper switch, windshield intermittent wiper switch, windshield low-speed wiper switch, windshield high-speed wiper switch or windshield washer switch signal is not sent to the ETACS-ECU."

STEP 4. Check the windshield wiper motor.




1. Disconnect the windshield wiper motor connector A-03.
2. Connect a battery to the windshield wiper motor as shown. Then check 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 operates normally when the windshield wiper switch is moved to each position.










STEP 5. Check windshield wiper motor connector A-03 and front-ECU connector A-11X for loose, corroded or damaged terminals, or terminals
pushed back in the connector.

Q: Are windshield wiper motor connector A-03 and front-ECU connector A-11X in good condition?

YES : Go to Step 6.

NO : Repair or replace the damaged components). Refer to Harness Connector Inspection. Verify that the windshield wiper operates normally when the windshield wiper switch is moved to each position.













STEP 6. Check the wiring harness between windshield wiper motor connector A-03 (terminals 1 and 2) and front-ECU connector A-11X (terminals 27 and 28).

NOTE: Also check intermediate connector C-05 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-05 is damaged, repair or replace the damaged components) as described in Harness Connector Inspection.

Q: Is the wiring harness between windshield wiper motor connector A-03 (terminals 1 and 2) and front-ECU connector A-12X (terminals 27 and 28) 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 windshield wiper operates normally when the windshield wiper switch is moved to each position.