Inspection Procedure O-15

INSPECTION PROCEDURE O-15: Column switch: 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.






CIRCUIT OPERATION
The ETACS-ECU uses the input signal from the column switch (windshield wiper and washer switch) to operate various functions.

TECHNICAL DESCRIPTION (COMMENT)
The column switch (windshield wiper and washer switch) input signal is used to operate the windshield wiper and washer. If the signal fails, windshield wiper and washer will not work normally.

TROUBLESHOOTING HINTS
- The column switch (windshield wiper and washer switch) may be defective
- The ETACS-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. Verify the ignition switch positions.

Q: Does a diagnostic trouble code set when the ignition switch is at any of the positions?

YES: Carry out the troubleshooting by referring to the Diagnostic Trouble Code Chart. Testing and Inspection
NO: Go to Step 2.







STEP 2. Check the windshield wiper and washer switch.

Q: Is the windshield wiper and washer switch in good condition?

YES: Go to Step 3.
NO: Replace it. The input signal from the column switch (windshield wiper and washer switch) should be able to be checked and the windshield wiper and washer should work normally.

STEP 3. Replacement of ECU

1. Replace the column switch (turn-signal light and lighting switch).
2. The input signal from the column switch (windshield wiper and washer switch) should be able to be checked and the windshield wiper and washer should work normally.

Q: Is the input signal from the column switch (windshield wiper and washer switch) input normally?

YES: No action is necessary and testing is complete.
NO: Replace the ETACS-ECU. The input signal from the column switch (windshield wiper and washer switch) should be able to be checked and the windshield wiper and washer should work normally.