Inspection Procedure 5

INSPECTION PROCEDURE 5: The windshield intermittent wiper interval cannot be adjusted by operating the windshield intermittent wiper interval 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
- 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 column switch 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
- MB991910: M.U.T.-III Main Harness A

STEP 1. Use the scan tool MB991958 to check if an ETACS-related diagnostic trouble code is set.







Connect the scan tool. Refer to chassis electrical ETACS, "How to connect the scan tool (M.U.T.-III)"

Q: Is the diagnostic trouble code set?

YES: Diagnose the ETACS-ECU. Refer to chassis electrical ETACS, "Diagnostic trouble code chart"

NO: Go to Step 2.

STEP 2. Check the ETACS customization function.
Use the ETACS customization 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 customization 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 windshield wiper operation.
- Ignition switch: ACC
- Rotate the windshield wiper interval control from (+) to () side.







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 interval control is rotated.

Q: Is the check result normal?

YES: Intermittent malfunction. Refer to general (body and chassis), How to cope with intermittent malfunction.

NO: Replace the ETACS-ECU.