Inspection Procedure F-6

Windshield Wiper and Washer: The Windshield Intermittent Wiper Interval is not Changed According to the Vehicle Speed

Windshield Intermittent Wiper Circuit:

NOTE: This troubleshooting requires use of scan tool MB991502 and SWS monitor kit MB991862. For details of how to use the SWS monitor, refer to "How to use SWS monitor".

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
- Malfunction of the ETACS-ECU
- Malfunction of the front-ECU
- Damaged harness wires or connectors

DIAGNOSIS

Required Special Tools:
- MB991223: Test Harness Set
- MB991502: Scan Tool (MUT-II)
- MB991862: SWS monitor kit




STEP 1. Check the input signal (by using the Pulse check).

Check the vehicle speed signal or the input signals from the vehicle speed sensor .

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 scan tool MB991502 sounds when the vehicle speed exceeds 10 kph (6.2 mph).

Q: Does scan tool MB991502 sound when the vehicle speed exceeds 10 kph (6.2 mph)?

YES: Go to Step 2.

NO: Refer to Inspection Procedure M-2 "ETACS-ECU does not receive the vehicle speed signal or a signal from the vehicle speed sensor ."


STEP 2. Check the input signal by using service data 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 MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502. Also connect SWS monitor kit MB991862 after turning on scan tool MB991502.

1. Connect SWS monitor kit MB991862 to the column switch connector.

2. Select "WIPER - F. WIPER INT" (FUNCTION DIAG.), and 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 kph (0 mph) to 25 kph (15.5 mph).

Q: Does 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.