Inspection Procedure G-6

Windshield Wiper and Washer: The windshield intermittent wiper interval is not changed according to the vehicle speed.

NOTE: This troubleshooting procedure requires the use of scan tool MB991958 and SWS monitor kit MB991813. For details on how to use the SWS monitor, refer to "How to use SWS monitor."

Windshield Intermittent Wiper Circuit:

TECHNICAL DESCRIPTION (COMMENT)
If the windshield intermittent wiper interval is not changed according to the vehicle speed, the ETACS-ECU or the front-ECU may be defective.

TROUBLESHOOTING HINTS
- Trouble in input signal system
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
- The front-ECU may be defective
- The ETACS-ECU may be defective

DIAGNOSIS

Required Special Tools:
- MB991223: Harness Set
- MB992006: Extra Fine Probe
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: M.U.T.-III USB Cable
- MB991911: M.U.T.-III Main Harness B
- MB991813: SWS monitor kit
- MB991806: SWS monitor cartridge
- MB991812: SWS monitor harness (for column-ECU)
- MB991922: Probe harness

STEP 1. Check the input signal (by using the pulse check mode of the monitor).
Check the input signals from the vehicle speed sensor.

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958. Connect special tool MB991911 before connecting special tool MB991812. Be sure to connect special tool MB991806 after turning on special tool MB991824.




1. Connect the special tool. Refer to "How to connect SWS monitor."
2. Operate scan tool MB991958 according to the procedure below to display "pulse check."
a. Select "SYSTEM SELECT."
b. Select "SWS."
c. Select "Pulse Checking."

3. Check that scan tool MB991958 sounds when the vehicle speed exceeds 10 km/h (6.2 mph).

Q: Does scan tool MB991958 sound when the vehicle speed exceeds 10 km/h (6.2 mph)?

YES: Go to Step 2.

NO: Refer to Inspection Procedure O-8 "The ETACS-ECU does not receive any signal from the vehicle speed sensor."

STEP 2. Check the input signal by using "FUNCTION DIAG." menu of the SWS monitor.
Set each switch to the following condition to check input signals from the windshield intermittent wiper interval adjusting knob:
- Ignition switch: ACC
- Windshield wiper switch: INT
- Intermittent wiper adjusting knob: SLOW side

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958. Connect special tool MB991911 before connecting special tool MB991812. Be sure to connect special tool MB991806 after turning on special tool MB991824.




1. Connect the special tool. Refer to "How to connect SWS monitor."
2. Operate scan tool MB991958 according to the procedure below to display "F. WIPER INT."
a. Select "Interactive Diagnosis."
b. Select "System select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "Function Diag."
f. Select "WIPER."
g. Select "F. WIPER INT."




3. Check that normal conditions are displayed on the items described in the table.

NOTE: Also check that the wiper interval changes smoothly when the vehicle is accelerated from 0 km/h (0 mph) to 25 km/h(15.5mph).

Q: Does scan tool MB991958 display the item "INT WIPER TIME" as the value change within the normal range when the windshield intermittent wiper interval adjusting knob is rotated?

YES: Replace the front-ECU. The windshield intermittent wiper interval should change according to the vehicle speed.

NO: Replace the ETACS-ECU. The windshield intermittent wiper interval should change according to the vehicle speed.